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Controllers and Memory Cards

Controllers/Memory Cards

Controller and Memory Card I/O Ports
Controller and Memory Card Misc
Controller and Memory Card Signals
Controller and Memory Card Multitap Adaptor

Controllers

Controllers - Communication Sequence
Controllers - Standard Digital/Analog Controllers
Controllers - Mouse
Controllers - Racing Controllers
Controllers - Lightguns
Controllers - Rumble Configuration
Controllers - Dance Mats
Controllers - Pop'n Controllers
Controllers - Densha de Go! / Jet de Go! Controllers
Controllers - Stepper Controller
Controllers - Fishing Controllers
Controllers - I-Mode Adaptor (Mobile Internet)
Controllers - Additional Inputs
Controllers - Misc

Memory Cards

Memory Card Read/Write Commands
Memory Card Data Format
Memory Card Images
Memory Card Notes

Pocketstation (Memory Card with built-in LCD screen and buttons)

Pocketstation

Pinouts

Pinouts - Controller Ports and Memory-Card Ports

Controller and Memory Card I/O Ports

1F801040h JOY_TX_DATA (W)

  0-7   Data to be sent
  8-31  Not used

Writing to this register starts the transfer (if, or as soon as TXEN=1 and JOY_STAT.2=Ready), the written value is sent to the controller or memory card, and, simultaneously, a byte is received (and stored in RX FIFO if JOY_CTRL.1 or JOY_CTRL.2 is set).
The "TXEN=1" condition is a bit more complex: Writing to SIO_TX_DATA latches the current TXEN value, and the transfer DOES start if the current TXEN value OR the latched TXEN value is set (ie. if TXEN gets cleared after writing to SIO_TX_DATA, then the transfer may STILL start if the old latched TXEN value was set).

1F801040h JOY_RX_DATA (R)

  0-7   Received Data      (1st RX FIFO entry) (oldest entry)
  8-15  Preview            (2nd RX FIFO entry)
  16-23 Preview            (3rd RX FIFO entry)
  24-31 Preview            (4th RX FIFO entry) (5th..8th cannot be previewed)

A data byte can be read when JOY_STAT.1=1. Data should be read only via 8bit memory access (the 16bit/32bit "preview" feature is rather unusable, and usually there shouldn't be more than 1 byte in the FIFO anyways).

1F801044h JOY_STAT (R)

  0     TX Ready Flag 1   (1=Ready/Started)
  1     RX FIFO Not Empty (0=Empty, 1=Not Empty)
  2     TX Ready Flag 2   (1=Ready/Finished)
  3     RX Parity Error   (0=No, 1=Error; Wrong Parity, when enabled)  (sticky)
  4     Unknown (zero)    (unlike SIO, this isn't RX FIFO Overrun flag)
  5     Unknown (zero)    (for SIO this would be RX Bad Stop Bit)
  6     Unknown (zero)    (for SIO this would be RX Input Level AFTER Stop bit)
  7     /ACK Input Level  (0=High, 1=Low)
  8     Unknown (zero)    (for SIO this would be CTS Input Level)
  9     Interrupt Request (0=None, 1=IRQ7) (See JOY_CTRL.Bit4,10-12)   (sticky)
  10    Unknown (always zero)
  11-31 Baudrate Timer    (21bit timer, decrementing at 33MHz)

1F801048h JOY_MODE (R/W) (usually 000Dh, ie. 8bit, no parity, MUL1)

  0-1   Baudrate Reload Factor (1=MUL1, 2=MUL16, 3=MUL64) (or 0=MUL1, too)
  2-3   Character Length       (0=5bits, 1=6bits, 2=7bits, 3=8bits)
  4     Parity Enable          (0=No, 1=Enable)
  5     Parity Type            (0=Even, 1=Odd) (seems to be vice-versa...?)
  6-7   Unknown (always zero)
  8     CLK Output Polarity    (0=Normal:High=Idle, 1=Inverse:Low=Idle)
  9-15  Unknown (always zero)

1F80104Ah JOY_CTRL (R/W) (usually 1003h,3003h,0000h)

  0     TX Enable (TXEN)  (0=Disable, 1=Enable)
  1     /JOYn Output      (0=High, 1=Low/Select) (/JOYn as defined in Bit13)
  2     RX Enable (RXEN)  (0=Normal, when /JOYn=Low, 1=Force Enable Once)
  3     Unknown? (read/write-able) (for SIO, this would be TX Output Level)
  4     Acknowledge       (0=No change, 1=Reset JOY_STAT.Bits 3,9)          (W)
  5     Unknown? (read/write-able) (for SIO, this would be RTS Output Level)
  6     Reset             (0=No change, 1=Reset most JOY_registers to zero) (W)
  7     Not used             (always zero) (unlike SIO, no matter of FACTOR)
  8-9   RX Interrupt Mode    (0..3 = IRQ when RX FIFO contains 1,2,4,8 bytes)
  10    TX Interrupt Enable  (0=Disable, 1=Enable) ;when JOY_STAT.0-or-2 ;Ready
  11    RX Interrupt Enable  (0=Disable, 1=Enable) ;when N bytes in RX FIFO
  12    ACK Interrupt Enable (0=Disable, 1=Enable) ;when JOY_STAT.7  ;/ACK=LOW
  13    Desired Slot Number  (0=/JOY1, 1=/JOY2) (set to LOW when Bit1=1)
  14-15 Not used             (always zero)

Caution: After slot selection (via Bits 1,13), one should issue a delay before sending the the first data byte: Digital Joypads may work without delay, Dualshock and Mouse require at least some small delay, and older Analog Joypads require a huge delay (around 500 clock cycles for SCPH-1150), official kernel waits more than 2000 cycles (which is much more than needed).

1F80104Eh JOY_BAUD (R/W) (usually 0088h, ie. circa 250kHz, when Factor=MUL1)

  0-15  Baudrate Reload value for decrementing Baudrate Timer

Timer reload occurs when writing to this register, and, automatically when the Baudrate Timer reaches zero. Upon reload, the 16bit Reload value is multiplied by the Baudrate Factor (see 1F801048h.Bit0-1), divided by 2, and then copied to the 21bit Baudrate Timer (1F801044h.Bit11-31). The 21bit timer decreases at 33MHz, and, it ellapses twice per bit (once for CLK=LOW and once for CLK=HIGH).

  BitsPerSecond = (44100Hz*300h) / MIN(((Reload*Factor) AND NOT 1),1)

The default BAUD value is 0088h (equivalent to 44h cpu cycles), and default factor is MUL1, so CLK pulses are 44h cpu cycles LOW, and 44h cpu cycles HIGH, giving it a transfer rate of circa 250kHz per bit (33MHz divided by 88h cycles).
Note: The Baudrate Timer is always running; even if there's no transfer in progress.

/IRQ7 (/ACK) Controller and Memory Card - Byte Received Interrupt

Gets set after receiving a data byte - that only if an /ACK has been received from the peripheral (ie. there will be no IRQ if the peripheral fails to send an /ACK, or if there's no peripheral connected at all).

  Actually, /IRQ7 means "more-data-request",
  accordingly, it does NOT get triggered after receiving the LAST byte.

I_STAT.7 is edge triggered (that means it can be acknowledge before or after acknowledging JOY_STAT.9). However, JOY_STAT.9 is NOT edge triggered (that means it CANNOT be acknowledged while the external /IRQ input is still low; ie. one must first wait until JOY_STAT.7=0, and then set JOY_CTRL.4=1) (this is apparently a hardware glitch; note: the LOW duration is circa 100 clock cycles).

/IRQ10 (/IRQ) Controller - Lightpen Interrupt

Pin8 on Controller Port. Routed directly to the Interrupt Controller (at 1F80107xh). There are no status/enable bits in the JOY_registers (at 1F80104xh).

RX FIFO / TX FIFO Notes

The JOY registers can hold up to 8 bytes in RX direction, and almost 2 bytes in TX direction (just like the SIO registers, see there for details), however, normally only 1 byte should be in the RX/TX registers (one shouldn't send a 2nd byte until /ACK is sensed, and, since the transfer CLK is dictated by the CPU, the amount of incoming data cannot exceed 1 byte; provided that one reads received response byte after each transfer).
Unlike SIO, the JOY status register doesn't have a RX FIFO Overrun flag.

General Notes

RXEN should be usually zero (the hardware automatically enables receive when /JOYn is low). When RXEN is set, the next transfer causes data to be stored in RX FIFO even when /JOYn is high; the hardware automatically clears RXEN after the transfer.
For existing joypads and memory cards, data should be always transferred as 8bit no parity (although the JOY registers do support parity just like SIO registers).

Plugging and Unplugging Cautions

During plugging and unplugging, the Serial Data line may be dragged LOW for a moment; this may also affect other connected devices because the same Data line is shared for all controllers and memory cards (for example, connecting a joypad in slot 1 may corrupt memory card accesses in slot 2).
Moreover, the Sony Mouse does power-up with /ACK=LOW, and stays stuck in that state until it is accessed at least once (by at least sending one 01h byte to its controller port); this will also affect other devices (as a workaround one should always access BOTH controller ports; even if a game uses only one controller, and, code that waits for /ACK=HIGH should use timeouts).

Emulation Note

After sending a byte, the Kernel waits 100 cycles or so, and does THEN acknowledge any old IRQ7, and does then wait for the new IRQ7. Due to that bizarre coding, emulators can't trigger IRQ7 immediately within 0 cycles after sending the byte.

Controller and Memory Card Misc

BIOS Functions

Controllers can be probably accessed via InitPad and StartPad functions,
BIOS Joypad Functions
Memory cards can be accessed by the filesystem (with device names "bu00:" (slot1) and "bu10:" (slot2) or so). Before using that device names, it seems to be required to call InitCard, StartCard, and _bu_init (?).

Connectors

The PlayStation has four connectors (two controllers, two memory cards),

  Memory Card 1         Memory Card 2
  Controller 1          Controller 2

The controller ports have 9 pins, the memory cards only 8 pins. However, there are only 10 different pins in total.

  JOYDAT,JOYCMD,JOYCLK  Data in/out/clock
  +7.5V,+3.5V,GND       Supply
  /JOY1,/JOY2  Selects controller/memorycard 1, or controller/memorycard 2
  /ACK         Indicates that the device is ready to send more data (IRQ7)
  /IRQ10       Lightgun (controllers only, not memory card) (IRQ10)

Most of these pins are shared for all 4 connectors (eg. a CLK signal meant to be sent to one device will also arrive at the other 3 devices).
The /JOYn signals are selecting BOTH the corresponding controller, and the corresponding memory card (whether it is a controller access or memory card access depends on the first byte transferred via the CMD line; this byte should be 01h=Controller, or 81h=Memory Card; or, a special case would be 21h=Yaroze Access Card).

Data In/Out

The data is transferred in units of bytes, via separate input and output lines. So, when sending byte, the hardware does simultaneously receive a response byte.
One exception is the first command byte (which selects either the controller, or the memory card) until that byte has been sent, neither the controller nor memory card are selected (and so the first "response" byte should be ignored; probably containing more or less stable high-z levels).
The other exception is, when you have send all command bytes, and still want to receive further data, then you'll need to send dummy command bytes (should be usually 00h) to receive the response bytes.

Controller and Memory Card Signals

Overview

       ____                                                              _____
  /SEL     |____________________________________________________________|
       ______        ____        ____        ____        ____        _________
  CLK        ||||||||    ||||||||    ||||||||    ||||||||    ||||||||
       _______________________________________________________________________
  CMD       X  01h   XXXX  42h   XXXX  00h   XXXX  00h   XXXX  00h   XXXX
            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
            _____________________________________________________________
  DAT  -----XXXXXXXXXXXXX   ID   XXXX  5Ah   XXXX  key1  XXXX  key2  XXXX-----
            ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  /ACK ---------------|_|---------|_|---------|_|---------|_|-----------------

Top command. First comminucation(device check)

       ____
  /SEL     |__________________________________________________________________
       ______   _   _   _   _   _   _   _   __________________   _   _   _   _
  CLK        |_| |_| |_| |_| |_| |_| |_| |_|                  |_| |_| |_| |_|
       __________                                                  ___
  CMD            |________________________________________________|   |_______
                                                              ____
  DAT  -----XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX    |___________
  /ACK ----------------------------------------------|___|--------------------

X = none, - = Hi-Z

* 0x81 is memory-card, 0x01 is standard-pad at top command.
* serial data transfer is LSB-First format.
* data is down edged output, PSX is read at up edge in shift clock.
* PSX expects No-connection if not returned Acknowledge less than 100 usec.
* clock pulse is 250KHz.
* no need Acknowledge at last data.
* Acknowledge signal width is more than 2 usec.
* time is 16msec between SEL from previous SEL.
* SEL- for memory card in PAD access.

Controller and Memory Card Multitap Adaptor

SCPH-1070 (Multitap)

The Multitap is an external adaptor that allows to connect 4 controllers, and 4 memory cards to one controller port. When using two adaptors (one on each slot), up to 8 controllers and 8 memory cards can be used.

The Multitap has a physical lip that blocks access to the memory card slot above the controller port it is plugged into. This is done to prevent ambiguity/contention between the memory card plugged into Multitap slot A and the memory card slot, since both are accessed via byte 0x81.

Multitap Controller Passthrough Mode

In passthrough mode, the access byte sent to the Multitap is 0Nh, where N is the desired pad. On receiving a valid access byte, the multitap will send a 01h access byte to the controller to activate it for transfer. All following bytes are passed through normally as if the software is communicating directly with the controller. If the initial Multitap access byte is out of range (i.e. not 01h, 02h, 03h, or 04h) or a controller is not plugged into the port, the Multitap will not ACK the access.

Multitap Controller Buffered Transfer All Mode

To activate the buffered Transfer All mode, 01h must be sent as the third byte in the controller transfer sequence (so the second byte in the command halfword), like so:

  0Nh 42h 01h ..

Sending any value other than 00h or 01h for that byte, in either operation mode, seems to cause the Multitap to end communication at that byte (no ACK). When activating buffered Transfer All mode, the current response is not affected. Instead, it signals the Multitap to send/receive data for all the controllers on the next transfer sequence, like so:

  Access Byte
  Halfword 0      --> Controller ID for MultiTap (5A80h=Multitap)
  Halfword 1..4   --> Player A (Controller ID, Buttons, Analog Inputs, if any)
  Halfword 5..8   --> Player B (Controller ID, Buttons, Analog Inputs, if any)
  Halfword 9..12  --> Player C (Controller ID, Buttons, Analog Inputs, if any)
  Halfword 13..16 --> Player D (Controller ID, Buttons, Analog Inputs, if any)

With this method, the Multitap always sends 4 halfwords per slot, padded with FFh for devices like Digital Controllers and Mice which use less than 4 halfwords. For Empty slots, all 4 halfwords are filled with FFh bytes.

A number of things can cause the Transfer All mode to fail. First, the controller corresponding to the access byte must be present, or the transfer will end on the access byte, same as for a passthrough transfer. Secondly, the command halfword must be 42h 00h or 42h 01h, or transfer will end on the second byte of the halfword.

In Transfer All mode, controller response are buffered by an entire transfer sequence, so software must request another Transfer All to receive the results from the previous Transfer All, like so:

  0Nh 42h 01h .. ; Passthrough, request Transfer All mode for next command
  0Nh 42h 01h .. ; Transfer All, responses should be ignored as previous mode was not Transfer All
  0Nh 42h 01h .. ; Transfer All, receive responses from previous Transfer All
  ..             ; And so forth
  0Nh 42h 00h .. ; Return to Passthrough mode on next transfer sequence if currently in Transfer All mode

The IRQ10 line (used by the Konami Justifier) is simply wired to all four slots via small resistors without any special logic for activating/deactivating the IRQ on specific slots.

Multitap Memory Card Access

Memory card access is done like so:

  8Nh xxh .. ..      ;access memory card in slot "N" (1..4)

There is no other known method for accessing memory cards through the Multitap.

Unverified notes from Nocash:
That's the way how its done in Silent Hill. Although for the best of confusion, it doesn't actually work in that game (probably the developer has just linked in the multitap library, without actually supporting the multitap at higher program levels).

Multitap Games

  Bomberman / Bomberman Party Edition (requires Multitap on Port 2 instead of 1)
  Bomberman World
  Breakout: Off the Wall Fun
  Circuit Breakers
  Crash Team Racing
  FIFA series soccer games
  Frogger
  Gauntlet: Dark Legacy
  Hot Shots Golf 2 & 3
  Jigsaw Island: Japan Graffiti / Jigsaw Madness (requires Multitap on Port 2 instead of 1)
  NBA Live (any year) (up to 8 players with two multitaps)
  Need For Speed 3
  Need For Speed 5
  Poy Poy (4 players hitting each other with rocks and trees)
  Running Wild
  S.C.A.R.S. (requires Multitap on Port 2 instead of 1)
  Zen Nippon Pro Wrestling: Ouja no Tamashii (requires Multitap on Port 2 instead of 1)

Most Multitap games supporting up to 4 or 5 controllers require the device to be plugged into Port 1, but a small number of games strangely require the device to be plugged into Port 2 instead.

Multitap Versions

                   .------.
   SCPH-1070       |      |        SCPH-111
   (gray case)     |      |        (white case)
   (for PSX)       |    D |        (for PSone)
                   |      |                   .----------------.
        cable      |      |        cable     .'   D        C   '.
            ''--.. |    C |         '''--..__|                  |
                  \|      |                  |                  |
  .----------------'      |                  '.   A        B   .'
  |                       |                   '----------------'
  |                       |
  |    A        B        /
  '---------------------'

The cable connects to one of the PSX controller ports (which also carries the memory card signals). The PSX memory card port is left unused (and is blocked by a small edge on the Multitap's plug).

Software-parsed Controller IDs

Halfword 0 is parsed (by the BIOS) as usually, ie. the LSB is moved to MSB, and LSB is replaced by status byte (so ID 5A80h becomes 8000h=Multitap/okay, or xxFFh=bad). Halfwords 1,5,9,13 are NOT parsed (neither by the BIOS nor by the Multitap hardware), however, some info in the internet is hinting that Sony's libraries might be parsing these IDs too (so for example 5A41h would become 4100h=DigitalPad/okay, or xxFFh=bad).

Power Supply

The Multitap is powered by the PSX controller port. Unknown if there are any power supply restrictions (up to eight controllers and eight cards may scratch some limits, especially when doing things like activating rumble on all joypads). However, the Multitap hardware itself doesn't do much on supply restrictions (+3.5V is passed through something; maybe some fuse, loop, or 1 ohm resistor or so) (and +7.5V is passed without any restrictions).

See also

Pinouts - Component List and Chipset Pin-Outs for Multitap, SCPH-1070

Controllers - Communication Sequence

Controller Communication Sequence

  Send Reply Comment
  01h  Hi-Z  Controller Access (unlike 81h=Memory Card access), dummy response
  42h  idlo  Receive ID bit0..7 (variable) and Send Read Command (ASCII "B")
  TAP  idhi  Receive ID bit8..15 (usually/always 5Ah)
  MOT  swlo  Receive Digital Switches bit0..7
  MOT  swhi  Receive Digital Switches bit8..15
  --- transfer stops here for digital pad (or analog pad in digital mode) ---
  00h  adc0  Receive Analog Input 0 (if any) (eg. analog joypad or mouse)
  00h  adc1  Receive Analog Input 1 (if any) (eg. analog joypad or mouse)
  --- transfer stops here for analog mouse ----------------------------------
  00h  adc2  Receive Analog Input 2 (if any) (eg. analog joypad)
  00h  adc3  Receive Analog Input 3 (if any) (eg. analog joypad)
  --- transfer stops here for analog pad (in analog mode) -------------------
  --- transfer stops here for nonstandard devices (steering/twist/paddle) ---

The TAP byte should be usually zero, unless one wants to activate Multitap (multi-player mode), for details, see
Controller and Memory Card Multitap Adaptor
The two MOT bytes are meant to control the rumble motors (for normal non-rumble controllers, that bytes should be 00h), however, the MOT bytes have no effect unless rumble is enabled via config commands, for details, see
Controllers - Rumble Configuration

Controller ID (Halfword Number 0)

  0-3  Number of following halfwords (01h..0Fh=1..15, or 00h=16 halfwords)
  4-7  Controller Type (or currently selected Controller Mode)
  8-15 Fixed (5Ah)

Known 16bit ID values are:

  xx00h=N/A                 (initial buffer value from InitPad BIOS function)
  5A12h=Mouse               (two button mouse)
  5A23h=NegCon              (steering twist/wheel/paddle)
  5A31h=Konami Lightgun     (IRQ10-type)
  5A41h=Digital Pad         (or analog pad/stick in digital mode; LED=Off)
  5A53h=Analog Stick        (or analog pad in "flight mode"; LED=Green)
  5A63h=Namco Lightgun      (Cinch-type)
  5A73h=Analog Pad          (in normal analog mode; LED=Red)
  5A80h=Multitap            (multiplayer adaptor) (when activated)
  5AE3h=Jogcon              (steering dial)
  5AF3h=Config Mode         (when in config mode; see rumble command 43h)
  FFFFh=High-Z              (no controller connected, pins floating High-Z)

Controllers - Standard Digital/Analog Controllers

       ___                      ___           ___                      ___
    __/_L_\__   Analog Pad   __/_R_\__     __/_L_\__  Digital Pad   __/_R_\__
   /    _    \--------------/         \   /    _    \--------------/         \
  |   _| |_   |            |     /\    | |   _| |_   |            |     /\    |
  |  |_ X _|  |SEL      STA|  []    () | |  |_ X _|  |            |  []    () |
  |    |_|  ___   ANALOG   ___   ><    | |    |_|    |  SEL  STA  |     ><    |
  |\______ / L \   LED    / R \ ______/| |\_________/--------------\_________/|
  |       | Joy |--------| Joy |       | |       |                    |       |
  |      / \___/          \___/ \      | |      /                      \      |
   \____/                        \____/   \____/                        \____/

Standard Controllers

  __Halfword 0 (Controller Info)_______________________________________________
  0-15  Controller Info  (5A41h=digital, 5A73h=analog/pad, 5A53h=analog/stick)
  __Halfword 1 (Digital Switches)______________________________________________
  0   Select Button    (0=Pressed, 1=Released)
  1   L3/Joy-button    (0=Pressed, 1=Released/None/Disabled) ;analog mode only
  2   R3/Joy-button    (0=Pressed, 1=Released/None/Disabled) ;analog mode only
  3   Start Button     (0=Pressed, 1=Released)
  4   Joypad Up        (0=Pressed, 1=Released)
  5   Joypad Right     (0=Pressed, 1=Released)
  6   Joypad Down      (0=Pressed, 1=Released)
  7   Joypad Left      (0=Pressed, 1=Released)
  8   L2 Button        (0=Pressed, 1=Released) (Lower-left shoulder)
  9   R2 Button        (0=Pressed, 1=Released) (Lower-right shoulder)
  10  L1 Button        (0=Pressed, 1=Released) (Upper-left shoulder)
  11  R1 Button        (0=Pressed, 1=Released) (Upper-right shoulder)
  12  /\ Button        (0=Pressed, 1=Released) (Triangle, upper button)
  13  () Button        (0=Pressed, 1=Released) (Circle, right button)
  14  >< Button        (0=Pressed, 1=Released) (Cross, lower button)
  15  [] Button        (0=Pressed, 1=Released) (Square, left button)
  __Halfword 2 (Right joystick) (analog pad/stick in analog mode only)_________
  0-7   adc0 RightJoyX (00h=Left, 80h=Center, FFh=Right)
  8-15  adc1 RightJoyY (00h=Up,   80h=Center, FFh=Down)
  __Halfword 3 (Left joystick) (analog pad/stick in analog mode only)__________
  0-7   adc2 LeftJoyX  (00h=Left, 80h=Center, FFh=Right)
  8-15  adc3 LeftJoyY  (00h=Up,   80h=Center, FFh=Down)

Analog Mode Note

On power-up, the controllers are in digital mode (with analog inputs disabled). Analog mode can be (de-)activated manually by pushing the Analog button. Alternately, analog mode can be (de-)activated by software via rumble configuration commands (though that's supported only on newer pads; those with two rumble motors). It is essential that emulators and any third-party hardware have a way of manually toggling analog mode, similar to original analog controllers, as certain games like Gran Turismo 1 will not attempt to enter analog mode on their own, even if they support analog controls and detect an analog controller.
Since analog pads boot in digital mode and will return the same ID byte as digital controllers, the most common way of distinguishing between the 2 is to send a Dualshock-only command (Typically command 43h - enter/exit config mode) and seeing how the controller responds to it.
The analog sticks are mechanically restricted to a "circular field of motion" (most joypads can reach "min/max" values only in "straight" horizontal or vertical directions, but not in "diagonal" directions).

Analog Joypad Range

               ...''''''''''...
       ____ .''________________''._____       ___ 00h
      |  .''                      ''.  |
      |.'                            '.|      ___ 10h
      .'                              '.
     :|                                |:
    : |                                | :    ___ 60h
   .' |            .''''''.            | '.
   :  |          .'        '.          |  :
   :  |          :          :          |  :   ___ 80h
   :  |          :          :          |  :
   :  |          '.        .'          |  :
   '. |            '......'            | .'   ___ A0h
    : |                                | :
     :|                                |:
      '.                              .'      ___ F0h
      |'.                            .'|
      |__'..______________________..'__|      ___ FFh
      .     '..                ..'     .
     00h       '''..........'''       FFh
   Big Circle   --> Mechanically possible field of motion
   Square Area  --> Digitally visible 8bit field of motion
   Small Circle --> Resting position when releasing the joystick

Example min/center/max values for three different pads:

  SCPH-1150          Min=(00,00), Mid: (72..90,79..AC), Max=(FF,FF) at 25'C
  SCPH-1200          Min=(0E,0E), Mid: (6C..8A,75..79), Max=(ED,ED) at 16'C
  SCPH-110           Min=(11,11), Mid: (8A..9F,70..96), Max=(FD,FD) at 16'C

Values may vary for other pads and/or different temperatures.

Dual Analog Pad in LED=Green Mode

Basically same as normal analog LED=Red mode, with following differences:

  ID is 5A53h (identifying itself as analog stick) (rather than analog pad)
  Left/right joy-buttons disabled (as for real analog stick, bits are always 1)
  Some buttons are re-arranged: bit9=L1 bit10=[] bit11=/\ bit12=R1 bit15=R2

Concerning the button names, the real analog-stick does NOT have re-arranged buttons (eg. it's L1 button is in bit10), however, concerning the button locations, the analog stick's buttons are arranged completely differently as on analog pads (so it might be rather uncomfortable to play analog stick games on analog pads in LED=Red mode; the LED=Green mode is intended to solve that problem).
Might be useful for a few analog-stick games like MechWarrior 2, Ace Combat 2, Descent Maximum, and Colony Wars. In most other cases the feature is rather confusing (that's probably why the LED=Green mode wasn't implemented on the Dual Shock).

See also

Pinouts - Component List and Chipset Pin-Outs for Digital Joypad, SCPH-1080
Pinouts - Component List and Chipset Pin-Outs for Analog Joypad, SCPH-1150
Pinouts - Component List and Chipset Pin-Outs for Analog Joypad, SCPH-1200
Pinouts - Component List and Chipset Pin-Outs for Analog Joypad, SCPH-110

Controllers - Mouse

Sony Mouse Controller

  __Halfword 0 (Controller Info)________________
  0-15  Controller Info  (5A12h=Mouse)
  __Halfword 1 (Mouse Buttons)__________________
  0-7   Not used         (All bits always 1)
  8-9   Unknown          (Seems to be always 0) (maybe SNES-style sensitivity?)
  10    Right Button     (0=Pressed, 1=Released)
  11    Left Button      (0=Pressed, 1=Released)
  12-15 Not used         (All bits always 1)
  __Halfword 2 (Mouse Motion Sensors)___________
  0-7   Horizontal Motion (-80h..+7Fh = Left..Right) (00h=No motion)
  8-15  Vertical Motion   (-80h..+7Fh = Up..Down)    (00h=No motion)

Sony Mouse Hardware Bug on Power-On

On Power-on (or when newly connecting it), the Sony mouse does draw /ACK to LOW on power-on, and does then hold /ACK stuck in the LOW position.
For reference: Normal controllers and memory cards set /ACK=LOW only for around 100 clk cycles, and only after having received a byte from the console.
The /ACK pin is shared for both controllers and both memory cards, so the stuck /ACK is also "blocking" all other connected controllers/cards. To release the stuck /ACK signal: Send a command (at least one 01h byte) to both controller slots.

Sony Mouse Compatible Games

  3D Lemmings
  Alien Resurrection
  Area 51
  Ark of Time
  Atari Anniversary Edition
  Atlantis: The Lost Tales
  Breakout: Off the Wall Fun
  Broken Sword: The Shadow of the Templars
  Broken Sword II: The Smoking Mirror
  Clock Tower: The First Fear
  Clock Tower II: The Struggle Within
  Command & Conquer: Red Alert
  Command & Conquer: Red Alert - Retaliation
  Constructor (Europe)
  Die Hard Trilogy
  Die Hard Trilogy 2: Viva Las Vegas
  Discworld
  Discworld II: Missing Presumed...!?
  Discworld Noir
  Dracula - The Resurrection
  Dune 2000
  Final Doom
  Galaxian 3
  Ghoul Panic
  Klaymen Klaymen: Neverhood no Nazon (Japan)
  Lemmings and Oh No! More Lemmings
  Monopoly
  Music 2000
  Myst
  Neorude (Japan)
  Perfect Assassin
  Policenauts (Japan)
  Puchi Carat
  Quake II
  Railroad Tycoon II
  Rescue Shot
  Risk
  Riven: The Sequel to Myst
  RPG Maker
  Sentinel Returns
  SimCity 2000
  Syndicate Wars
  Tempest 2000 (Tempest X3)
  Theme Aquarium (Japan)
  Transport Tycoon
  Warhammer: Dark Omen
  Warzone 2100
  X-COM: Enemy Unknown
  X-COM: Terror from the Deep
  Z

Note: There are probably many more mouse compatible games.
Certain games, mostly FPS games such as Quake II and Doom, have players plug a standard digital/analog pad in port 1 and a mouse in port 2. This way, players can use the mouse for aiming and shooting, while the pad can be used for moving, reloading, and so on.

Sony Mouse Component List

PCB "TD-T41V/\, MITSUMI"
Component Side:

  1x 3pin   4.00MHz "[M]4000A, 85 2"
  2x 2pin   button (left/right)
  1x 8pin   connector (to cable with shield and 7 wires)
  1x 3pin   "811, T994I"
  2x 3pin   photo transistor (black)  ;\or so, no idea which one is
  2x 2pin   photo diode (transparent) ;/sender and which is sensor
  1x 2pin   electrolyt capacitor 16V, 10uF

Solder/SMD Side:

  1x 32pin  "(M), SC442116, FB G22K, JSAA815B"
  1x 14pin  "BA10339F, 817 L67" (Quad Comparator)
  2x 3pin   "LC" (amplifier for photo diodes)
  1x 3pin   "24-" (looks like a dual-diode or so)
  plus many SMD resistors/capacitors

Cable:

  PSX.Controller.Pin1 JOYDAT ---- brown  -- Mouse.Pin4
  PSX.Controller.Pin2 JOYCMD ---- red    -- Mouse.Pin3
  PSX.Controller.Pin3 +7.5V  ---- N/A
  PSX.Controller.Pin4 GND    ---- orange -- Mouse.Pin7 GND (G)
  PSX.Controller.Pin5 +3.5V  ---- yellow -- Mouse.Pin1
  PSX.Controller.Pin6 /JOYn  ---- green  -- Mouse.Pin5
  PSX.Controller.Pin7 JOYCLK ---- blue   -- Mouse.Pin2
  PSX.Controller.Pin8 /IRQ10 ---- N/A
  PSX.Controller.Pin9 /ACK   ---- purple -- Mouse.Pin6
  PSX.Controller.Shield --------- shield -- Mouse.Pin8 GND (SHIELD)

RS232 Mice

Below is some info on RS232 serial mice. That info isn't directly PSX related as the PSX normally doesn't support those mice.
With some efforts, one can upgrade the PSX SIO port to support RS232 voltages, and with such a modded console one could use RS232 mice (in case one wants to do that).
The nocash PSX bios can map a RS232 mouse to a spare controller slot (thereby simulating a Sony mouse), that trick may work with various PSX games.

Standard Serial Mouse

A serial mouse should be read at 1200 bauds, 7 data bits, no parity, 1 stop bit (7N1) with DTR and RTS on. For best compatibility, the mouse should output 2 stop bits (so it could be alternately also read as 7N2 or 8N1). When the mouse gets moved, or when a button gets pressed/released, the mouse sends 3 or 4 characters:

  __First Character____________________
  6    First Character Flag (1)
  5    Left Button  (1=Pressed)
  4    Right Button (1=Pressed)
  2-3  Upper 2bit of Vertical Motion
  0-1  Upper 2bit of Horizontal Motion
  __Second Character___________________
  6    Non-first Character Flag (0)
  5-0  Lower 6bit of Horizontal Motion
  __Third Character____________________
  6    Non-first Character Flag (0)
  5-0  Lower 6bit of Vertical Motion
  __Fourth Character (if any)__________
  6    Non-first Character Flag (0)
  5    Middle Button (1=Pressed)
  4    Unused ???
  3-0  Wheel  ???

Additionally, the mouse outputs a detection character (when switching RTS (or DTR?) off and on:

  "M" = Two-Button Mouse (aka "Microsoft" mouse)
  "3" = Three-Button Mouse (aka "Logitech" mouse)
  "Z" = Mouse-Wheel

Normally, the detection response consist of a single character (usually "M"), though some mice have the "M" followed by 11 additional characters of garbage or version information (these extra characters have bit6=0, so after detection, one should ignore all characters until receiving the first data character with bit6=1).

Mouse Systems Serial Mouse (rarely used)

Accessed at 1200 bauds, just like standard serial mouse, but with 8N1 instead 7N1, and with different data bytes.

  __First Byte_________________________
  7-3  First Byte Code (10000b)
  2    Left? Button   (0=Pressed)
  1    Middle? Button (0=Pressed)
  0    Right? Button  (0=Pressed)
  __Second Byte________________________
  7-0  Horizontal Motion (X1)
  __Third Byte_________________________
  7-0  Vertical Motion   (Y1)
  __Fourth Byte________________________
  7-0  Horizontal Motion (X2)
  __Fifth Byte_________________________
  7-0  Vertical Motion   (Y2)

The strange duplicated 8bit motion values are usually simply added together, ie. X=X1+X2 and Y=Y1+Y2, producing 9bit motion values.

Notes

The Sony Mouse connects directly to the PSX controller port. Alternately serial RS232 mice can be connected to the SIO port (with voltage conversion adaptor) (most or all commercial games don't support SIO mice, nor does the original BIOS do so, however, the nocash BIOS maps SIO mice to unused controller slots, so they can be used even with commercial games; if the game uses BIOS functions to read controller data).
Serial Mice (and maybe also the Sony mouse) do return raw mickeys, so effects like double speed threshold must (should) be implemented by software. Mice are rather rarely used by PSX games. The game "Perfect Assassin" includes ultra-crude mouse support, apparently without threshold, and without properly matching the cursor range to the screen resolution.

Controllers - Racing Controllers

neGcon Racing Controller (Twist) (NPC-101/SLPH-00001/SLEH-0003)

  __Halfword 0 (Controller Info)_______________________________________________
  0-15  Controller Info  (5A23h=neGcon)
  __Halfword 1 (Digital Switches)______________________________________________
  0-2   Not used       (always 1)       (would be Select, L3, R3 on other pads)
  3     Start Button   (0=Pressed, 1=Released)
  4     Joypad Up      (0=Pressed, 1=Released)
  5     Joypad Right   (0=Pressed, 1=Released)
  6     Joypad Down    (0=Pressed, 1=Released)
  7     Joypad Left    (0=Pressed, 1=Released)
  8-10  Not used       (always 1)       (would be L2, R2, L1 on other pads)
  11    R Button       (0=Pressed, 1=Released) (would be R1 on other pads)
  12    B Button       (0=Pressed, 1=Released) (would be /\ on other pads)
  13    A Button       (0=Pressed, 1=Released) (would be () on other pads)
  14-15 Not used       (always 1)              (would be ><, [] on other pads)
  __Halfword 2 (Right joystick) (analog pad/stick in analog mode only)_________
  0-7   Steering Axis    (00h=Left, 80h=Center, FFh=Right) (or vice-versa?)
  8-15  Analog I button  (00h=Out ... FFh=In)  (Out=released, in=pressed?)
  __Halfword 3 (Left joystick) (analog pad/stick in analog mode only)__________
  0-7   Analog II button (00h=Out ... FFh=In)  (Out=released, in=pressed?)
  8-15  Analog L button  (00h=Out ... FFh=In)  (Out=released, in=pressed?)

The Twist controller works like a paddle or steering wheel, but doesn't have a wheel or knob, instead, it can be twisted: To move into one direction (=maybe right?), turn its right end away from you (or its left end towards you). For the opposite direction (=maybe left?), do it vice-versa.

     _____         _  _         _____                              ____
    |__L__\_______/ || \_______/__R__|                            /    \
   /    _   namco   ||   neGcon       \                          /      \
  |   _| |_         ||            B    |                        |       |
  |  |_ X _|    ....||....     II   A  | .... Rotation Axis ... | ...  \|/
  |    |_|          ||            I    |                        |
  |        START    ||                 |                         \
  |       ________  ||  ________       |                          \__\
  |      /        \_||_/        \      |                             /
   \____/                        \____/

Namco Volume Controller (a paddle with two buttons) (SLPH-00015)

This is a cut-down variant of the neGcon, just a featureless small box. It does have the same ID value as neGcon (ID=5A23h), but, it excludes most digital, and all analog buttons.

   _______
  | namco |      Halfword 1 (digital buttons):
  |       |      Bit3  Button A (0=Pressed) (aka neGcon Start button)
  | A   B |      Bit13 Button B (0=Pressed) (aka neGcon A button aka () button)
  |       |      Other bits     (not used, always 1)
  |   _   |      Halfword 2 and 3 (analog inputs):
  |  (_)  |      Steering Axis  (00h..FFh)  (as for neGcon)
  |_______|      Analog I,II,L button values (not used, always 00h)

SANKYO N.ASUKA aka Nasca Pachinco Handle (SLPH-00007)

Another cut-down variant of the neGcon (with ID=5A23h, too). But, this one seems to have only one button. Unlike Namco's volume controller it doesn't look featureless. It looks pretty much as shown in the ascii-arts image below. Seems to be supported by several irem titles. No idea what exactly it is used for, it's probably not a sewing machine controller, nor an electronic amboss.

   ____ ____     Halfword 1 (digital buttons):
  |   /   _ \    Bit12 Button   (0=Pressed) (aka neGcon B button aka /\ button)
  |_ /   (_) )   Other bits     (not used, always 1)
  |_|___    /\   Halfword 2 and 3 (analog inputs):
   ____|   |_    Steering Axis  (00h..FFh)  (as for neGcon)
  |__________|   Analog I,II,L button values (not used, always 00h)

Mad Catz Steering Wheel (SLEH-0006)

A neGcon compatible controller. The Twist-feature has been replaced by a steering wheel (can be turned by 270 degrees), and the analog I and II buttons by foot pedals. The analog L button has been replaced by a digital button (ie. in neGcon mode, the last byte of the controller data can be only either 00h or FFh). When not using the pedals, the I/II buttons on the wheel can be used (like L button, they aren't analog though).

        __________________________
       /   ____________________   \    Stick
      /   /                    \   \    ___        Brakes  Gas
     /   (                      )   \  (   )         II     I
    /  I  \                    /  A  \  \ /          ___   ___
   / /\ II \____________MODE__/  B /\ \  |          |   | |   |
  | |  \ L  _                   R /  | | |          |!!!|_|!!!|___
  | |   ) _| |_   MadCatz        (   | |_|_        /|!!!| |!!!|  /
  | |  | |_ X _|                  |  | | | |      / |___| |___| /
  | |  |   |_|                    |  | |  /      / =========== /
  | |   \         SEL STA        /   | | /      / =========== /
   \ \__/ ______________________ \__/ / /      /_____________/
    \____/                      \____/_/
       |___________________________|

Unlike the neGon, the controller has Select, >\< and [] buttons, and a second set of L/R buttons (at the rear-side of the wheel) (no idea if L1/R1 or L2/R2 are at front?). Aside from the neGcon mode, the controller can be also switched to Digital mode (see below for button chart).

MadCatz Dual Force Racing Wheel

Same as above, but with a new Analog mode (additionally to Digital and neGcon modes). The new mode is for racing games that support only Analog Joypads (instead of neGcon). Additionally it supports vibration feedback.

MadCatz MC2 Vibration compatible Racing Wheel and Pedals

Same as above, but with a redesigned wheel with rearranged buttons, the digital pad moved to the center of the wheel, the L/R buttons at the rear-side of the wheel have been replaced by 2-way butterfly buttons ("pull towards user" acts as normal, the new "push away from user" function acts as L3/R3).

            ____________________
           /  ________________  \   ___ Stick      Brakes  Gas
          /  /       MC2      \  \ (   )             ___   ___
         /  /__________________\  \ \ /             |   | |   |
        |    A ()    _|_    I ><   | |              |!!!|_|!!!|___
        |   B /\ _    |    _ II [] | |             /|!!!| |!!!|  /
     ___|  L2   / \  STA  / \ R2   |_|_           / |___| |___| /
    /    \     /   | SEL |   \    /    \         / =========== /
   /  ____\    |___|     |___|   /____  \       / =========== /
  /__/     \____________________/     \__\     /_____________/

MadCatz Button Chart

  Mode     Buttons...................... Gas Brake Stick Wheel
  Digital  >< [] () /\ L1 R1 L2 R2 L1 R1 ><  ()    L1/R1 lt/rt
  Analog   >< [] () /\ L1 R1 L2 R2 L3 R3 UP  DN    L1/R1 LT/RT
  Negcon   I  II A  B  L  R  L  R  L  R  I   II    up/dn Twist

Whereas, lt/rt/up/dn=Digital Pad, UP/DN=Left Analog Pad Up/Down, LT/RT=Right Analog Pad Left/Right. Analog mode is supported only by the Dual Force and MC2 versions, L3/R3 only by the MC2 version.

Namco Jogcon (NPC-105/SLEH-0020/SLPH-00126/SLUH-00059)

  __Halfword 0 (Controller Info)___________________
  0-15  Controller Info  (5AE3h=Jogcon in Jogcon mode) (ie. not Digital mode)
 halfword1: buttons: same as digital pad
 halfword2:
   0    unknown (uh, this isn't LSB of rotation?)
   1-15 dial rotation (signed offset since last read?) (or absolute position?)
 halfword3:
   0    flag: dial was turned left  (0=no, 1=yes)
   1    flag: dial was turned right (0=no, 1=yes)
   2-15 unknown

Rotations of the dial are recognized by an optical sensor (so, unlike potentiometers, the dial can be freely rotated; by more than 360 degrees). The dial is also connected to a small motor, giving it a real force-feedback effect (unlike all other PSX controllers which merely have vibration feedback). Although that's great, the mechanics are reportedly rather cheap and using the controller doesn't feel too comfortable. The Jogcon is used only by Ridge Racer 4 for PS1 (and Ridge Racer 5 for PS2), and Breakout - Off the Wall Fun.
The Mode button probably allows to switch between Jogcon mode and Digital Pad mode (similar to the Analog button on other pads), not sure if the mode can be also changed by software via configuration commands...? Unknown how the motor is controlled; probably somewhat similar to vibration motors, ie. by the M1 and/or M2 bytes, but there must be also a way to select clockwise and anticlockwise direction)...? The controller does reportedly support config command 4Dh (same as analog rumble).

       ___       ________       ___
    __/_L_\__   /        \   __/_R_\__
   /    _    \ / LED MODE \-/         \
  |   _| |_   | SEL    STA |     /\    |
  |  |_ X _|  |  ________  |  []    () |
  |    |_|    | /        \ |     ><    |
  |\_________/\/          \/\__ ______/|
  |       |   |   JOGCON   |   |       |
  |       |   |    DIAL    |   |       |
  |       |    \          /    |       |
  |       |     \________/     |       |
  |       |                    |       |
  |       |                    |       |
   \_____/                      \_____/

Controllers - Lightguns

There are two different types of PSX lightguns (which are incompatible with each other).

Namco Lightgun (GunCon)

Namco's Cinch-based lightguns are extracting Vsync/Hsync timings from the video signal (via a cinch adaptor) (so they are working completely independed of software timings).
Controllers - Lightguns - Namco (GunCon)

Konami Lightgun (IRQ10)

Konami's IRQ10-based lightguns are using the lightgun input on the controller slot (which requires IRQ10/timings being properly handled at software side).
Controllers - Lightguns - Konami Justifier/Hyperblaster (IRQ10)
The IRQ10-method is reportedly less accurate (although that may be just due to bugs at software side).

Third-Party Lightguns

There are also a lot of unlicensed lightguns which are either IRQ10-based, or Cinch-based, or do support both.
For example, the Blaze Scorpion supports both IRQ10 and Cinch, and it does additionally have a rumble/vibration function; though unknown how that rumble feature is accessed, and which games are supporting it).

Lightgun Games

Controllers - Lightguns - PSX Lightgun Games

Compatibilty Notes (IRQ10 vs Cinch, PAL vs NTSC, Calibration)

Some lightguns are reportedly working only with PAL or only with NTSC games (unknown which guns, and unknown what is causing problems; the IRQ10 method should be quite hardware independed, the GunCon variant, too, although theoretically, some GunCon guns might have problems to extract Vsync/Hsync from either PAL or NTSC composite signals).
Lightguns from different manufacturers are reportedly returning slightly different values, so it would be recommended to include a calibration function in the game, using at least one calibration point (that would also resolve different X/Y offsets caused by modifying GP1 display control registers).
Lightguns are needing to sense light from the cathode ray beam; as such they won't work on regions of the screen that contain too dark/black graphics.

Controllers - Lightguns - Namco (GunCon)

GunCon Cinch-based Lightguns (Namco)

  __Halfword 0 (Controller Info)___________________
  0-15  Controller Info  (5A63h=Namco Lightgun; GunCon/Cinch Type)
  __Halfword 1 (Buttons)___________________________
  0-2   Not used              (All bits always 1)
  3     Button A (Left Side)  (0=Pressed, 1=Released) ;aka Joypad Start
  4-12  Not used              (All bits always 1)
  13    Trigger Button        (0=Pressed, 1=Released) ;aka Joypad O-Button
  14    Button B (Right Side) (0=Pressed, 1=Released) ;aka Joypad X-Button
  15    Not used              (All bits always 1)
  __Halfword 2 (X)_________________________________
  0-15  8MHz clks since HSYNC (01h=Error, or 04Dh..1CDh)
  __Halfword 3 (Y)_________________________________
  0-15  Scanlines since VSYNC (05h/0Ah=Error, PAL=20h..127h, NTSC=19h..F8h)

Caution: The gun should be read only shortly after begin of VBLANK.

Error/Busy Codes

Coordinates X=0001h, Y=0005h indicates "unexpected light":

  ERROR: Sensed light during VSYNC (eg. from a Bulb or Sunlight).

Coordinates X=0001h, Y=000Ah indicates "no light", this can mean either:

  ERROR: no light sensed at all (not aimed at screen, or screen too dark).
  BUSY: no light sensed yet (when trying to read gun during rendering).

To avoid the BUSY error, one should read the gun shortly after begin of VBLANK (ie. AFTER rendering, but still BEFORE vsync). Doing that isn't as simple as one might think:
On a NTSC console, time between VBLANK and VSYNC is around 30000 cpu clks, reading the lightgun (or analog joypads) takes around 15000 cpu clks. So, reading two controllers within that timeframe may be problematic (and reading up to eight controllers via multitaps would be absolutely impossible). As a workaround, one may arrange the read-order to read lightguns at VBLANK (and joypads at later time). If more than one lightgun is connected, then one may need to restrict reading to only one (or maybe: max two) guns per frame.

Minimum Brightness

Below are some average minimum brightness values, the gun may be unable to return position data near/below that limits (especially coordinates close to left screen border are most fragile). The exact limits may vary from gun to gun, and will also depend on the TV Set's brightness setting.

  666666h Minimum Gray
  770000h Minimum Blue
  007700h Minimum Green
  000099h Minimum Red

The gun does also work with mixed colors (eg. white bold text on black background works without errors, but the returned coordinates are a bit "jumpy" in that case; returning the position of the closest white pixels).
BUG: On a plain RED screen, aiming at Y>=00F0h, the gun is randomly returning either Y, or Y-80h (that error occurs in about every 2nd frame, ie. at 50% chance). It's strange... no idea what is causing that effect.

Coordinates

The coordinates are updated in all frames (as opposed to some lightguns which do update them only when pulling the trigger).
The absolute min/max coordinates may vary from TV set to TV set (some may show a few more pixels than others). The relation of the gun's Screen Coodinates to VRAM Coordinates does (obviously) depend on where the VRAM is located on the screen; ie. on the game's GP1(06h) and GP1(07h) settings.
Vertical coordinates are counted in scanlines (ie. equal to pixels). Horizontal coordinates are counted in 8MHz units (which would equal a resolution of 385 pixels; which can be, for example, converted to 320 pixel resolution as X=X*320/385).

Misinformation (from bugged homebrew source code)

  __Halfword 2 (X)_________________________________
  0-7   X-Coordinate  (actual: see X-Offset)             ;\with unspecified
  8-15  X-Offset      (00h: X=X-80, Nonzero: X=X-80+220) ;/dotclock?
  __Halfword 3 (Y)_________________________________
  0-7   Y-Coordinate  (actual: Y=Y-25) (but then, max is only 230, not 263 ?)
  8-15  Pad ID        (uh, what id?) (reportedly too dark/bright error flag?)

Namco Lightgun Drawing

           _-_______________________--_
  ----->  |    namco            \\\\   \    Namco G-Con 45 (light gray) (cinch)
  sensor   |............ .. .....\\\\...|_
          |_ :          :..   _____      _\
            |  O        :__../  )))|    (
             \__________/  |_\____/|     \
               :               :   |      |
               :               :   |      |  NPC-103
         A-Button (Left)   Trigger |      |  SLPH-00034/SLEH-0007/SLUH-00035
         B-Button (Right)          |______|

See also

Pinouts - Component List and Chipset Pin-Outs for Namco Lightgun, NPC-103

Controllers - Lightguns - Konami Justifier/Hyperblaster (IRQ10)

Overall IRQ10-Based Lightgun Access

  Send  01h 42h 00h x0h 00h
  Reply HiZ 31h 5Ah buttons

The purpose of the "x0h" byte is probably to enable IRQ10 (00h=off, 10h=on), this would allow to access more than one lightgun (with only one per frame having the IRQ enabled).

Standard IRQ10-based Lightguns (Konami)

The Controller Data simply consists of the ID and buttons states:

  __Halfword 0 (Controller Info)___________________
  0-15  Controller Info  (5A31h=Konami Lightgun; Timer/IRQ10 type)
  __Halfword 1 (Buttons)
  0-2   Not used                 (All bits always 1)
  3     Start Button (Left Side) (0=Pressed, 1=Released)  ;aka Joypad Start
  4-13  Not used                 (All bits always 1)
  14    Back Button  (Rear End)  (0=Pressed, 1=Released)  ;aka Joypad X-Button
  15    Trigger Button           (0=Pressed, 1=Released)  ;aka Joypad []-Button

The coordinates aren't part of the controller data, instead they must be read from Timer 0 and 1 upon receiving IRQ10 (see IRQ10 Notes below).

Konami Lightgun Drawing

     __                 ______ _
   _|__\_______________/  ___ \ \   Konami Justifier/Hyperblaster (light green)
  |   _______________ __ /   \ \ \
  |__|   _ _ _ _     |==|    O| \O\ .... Back Button (Rear End)
     |__:_:_:_:_:__  |___\__ /  ( (
                   |_|  ) \  :   \ \
      Trigger ......  \___/| :...|.|.... Start Button (Left Side)
                           |     | |
                           |     | | SLPH-00013/SLPH-00014/SLEH-0005/SLUH-00017
                          /     _|_|
                          \___--

Konami IRQ10 Notes

The PSX does have a lightgun input (Pin 8 of the controller), but, Sony did apparently "forget" to latch the current cathode ray beam coordinates by hardware when sensing the lightgun signal (quite strange, since that'd be a simple, inexpensive, and very obvious feature for a gaming console).
Instead, the lightgun signal triggers IRQ10, and the interrupt handler is intended to "latch" the coordinates by software (by reading Timer 0 and 1 values, which must configured to be synchronized with the GPU).
That method requires IRQ handling to be properly implemented in software (basically, IRQs should not be disabled for longer periods, and DMA transfers should not block the bus for longer periods). In practice, most programmers probably don't realize how to do that, to the worst, Sony seems to have delivered a slightly bugged library (libgun) to developers.
For details on Timers, see:
Timers
In some consoles, IRQ10 seems to be routed through a Secondary IRQ Controller, see:
EXP2 DTL-H2000 I/O Ports

IRQ10 Priority

For processing IRQ10 as soon as possible, it should be assigned higher priority than all other IRQs (ie. when using the SysEnqIntRP BIOS function, it should be the first/newest element in priority chain 0). The libgun stuff assigns an even higher priority by patching the BIOS exception handler, causing IRQ10 to be processed shortly before processing the priority chains (the resulting IRQ priority isn't actually higher as when using 1st element of chain 0; the main difference is that it skips some time consuming code which pushes registers R4..R30). For details on that patch, see:
BIOS Patches
Even if IRQ10 has highest priority, execution of (older) other IRQs may cause a new IRQ10 to be executed delayed (because IRQs are disabled during IRQ handling), to avoid that problem: Best don't enable any other IRQs except IRQ0 and IRQ10, or, if you need other IRQs, best have them enabled only during Vblank (there are no scanlines drawn during vblank, so IRQ10 should never trigger during that period). DMAs might also slow down IRQ execution, so best use them only during Vblank, too.

IRQ10 Timer Reading

To read the current timer values the IRQ10 handler would be required to be called \<immediately> after receiving the IRQ10 signal, which is more or less impossible; if the main program is trying to read a mul/div/gte result while the mul/div/gte operation is still busy may stop the CPU for some dozens of clock cycles, and active DMA transfers or cache hits and misses in the IRQ handler may cause different timings, moreover, timings may become completely different if IRQs are disabled (eg. while another IRQ is processed).
However, IRQ10 does also get triggered in the next some scanlines, so the first IRQ10 is used only as a notification that the CPU should watch out for further IRQ10's. Ie. the IRQ10 handler should disable all DMAs, acknowledge IRQ10, and then enter a waitloop that waits for the IRQ10 bit in I_STAT to become set again (or abort if a timeout occurs) and then read the timers, reportedly like so:

  IF NTSC then X=(Timer0-140)*0.198166, Y=Timer1
  IF PAL  then X=(Timer0-140)*0.196358, Y=Timer1

No idea why PAL/NTSC should use different factors, that factors are looking quite silly/bugged, theoretically, the pixel-to-clock ratio should be the exactly same for PAL and NTSC...?
Mind that reading Timer values in Dotclock/Hblank mode is unstable, for Timer1 this can be fixed by the read-retry method, for Timer0 this could be done too, but one would need to subtract the retry-time to get a correct coordinate; alternately Timer0 can run at system clock (which doesn't require read-retry), but it must be then converted to video clock (mul 11, div 7), and then from video clock to dot clock (eg. div 8 for 320-pixel mode).
Above can be repeated for the next some scanlines (allowing to take the medium values as result, and/or to eliminate faulty values which are much bigger or smaller than the other values). Once when you have collected enough values, disable IRQ10, so it won't trigger on further scanlines within the current frame.

IRQ10 Bugs

BUG: The "libgun" library doesn't acknowledge the old IRQ10 \<immediately> before waiting for a new IRQ10, so the timer values after sensing the new IRQ10 are somewhat random (especially for the first processed scanline) (the library allows to read further IRQ10's in further scanlines, which return more stable results).
No idea how many times IRQ10 gets typically repeated? Sporting Clays allocates a buffer for up to 20 scanlines (which would cause pretty much of a slowdown since the CPU is just waiting during that period) (nethertheless, the game uses only the first timer values, ie. the bugged libgun-random values).

Unknown if/how two-player games (with 2 lightguns) are working with the IRQ10 method... if IRQ10 is generated ONLY after pressing the trigger button, then it may work, unless both players have Trigger pressed at the same time... and, maybe one can enable/disable the lightguns by whatever commmand being sent to the controller (presumably that "x0h" byte, see above), so that gun 1 generates IRQ10 only in each second frame, and gun 2 only in each other frame...?

Controllers - Lightguns - PSX Lightgun Games

PSX Lightgun Games

Some games are working only with IRQ10 or only with Cinch, some games support both methods:

  Area 51 (Mesa Logic/Midway) (IRQ10)
  Crypt Killer (Konami) (IRQ10)
  Die Hard Trilogy 1: (Probe Entertainment) (IRQ10)
  Die Hard Trilogy 2: Viva Las Vegas (n-Space) (IRQ10/Cinch)
  Elemental Gearbolt (Working Designs) (IRQ10/Cinch)
  Extreme Ghostbusters: Ultimate Invasion (LSP) (Cinch)
  Galaxian 3 (Cinch)
  Ghoul Panic (Namco) (Cinch)
  Gunfighter: The Legend of Jesse James (Rebellion) (Cinch)
  Judge Dredd (Gremlin) (Cinch)
  Lethal Enforcers 1-2 (Konami) (IRQ10)
  Maximum Force (Midway) (IRQ10/Cinch)
  Mighty Hits Special (Altron) (EU/JPN) (Cinch)
  Moorhuhn series (Phenomedia) (Cinch)
  Point Blank 1-3 (Namco) (Cinch)
  Project Horned Owl (Sony) (IRQ10)
  Rescue Shot (Namco) (Cinch)
  Resident Evil: Gun Survivor (Capcom) (JPN/PAL versions) (Cinch)
  Silent Hill (IRQ10) ("used for an easter egg")
  Simple 1500 Series Vol.024 - The Gun Shooting (unknown type)
  Simple 1500 Series Vol.063 - The Gun Shooting 2 (unknown type)
  Snatcher (IRQ10)
  Sporting Clays (Charles Doty) (homebrew with buggy source code) (IRQ10/Cinch)
  Star Wars: Rebel Assault II (IRQ10)
  Time Crisis, and Time Crisis 2: Project Titan (Namco) (Cinch)

Note: The RPG game Dragon Quest Monsters does also contain IRQ10 lightgun code (though unknown if/when/where the game does use that code).

Controllers - Rumble Configuration

Rumble (aka "Vibration Function") is basically controlled by two previously unused bytes of the standard controller Read command.
There are two methods to control the rumble motors, the old method is very simple (but supports only one motor), the new method envolves a bunch of new configuration commands (and supports two motors).

  SCPH-1150 DualAnalog Pad with 1 motor                 ;-old rumble method
  SCPH-1200 DualAnalog Pad with 2 motors, PSX-design    ;\new rumble method
  SCPH-110  DualAnalog Pad with 2 motors, PSone-design  ;/
  Blaze Scorpion Lightgun with rumble      ;\unknow how to control rumble
  Fishing controllers with rumble          ;/
  SCPH-1180 Analog Pad without rumble      ;\unknow if there're config commands
  SCPH-1110 Analog Stick without rumble    ;/for analog mode (probably not)

Old Method, one motor, no config commands (SCPH-1150, SCPH-1200, SCPH-110)

The SCPH-1150 doesn't support any special config commands, instead, rumble is solely done via the normal joypad read command:

  Send  01h 42h 00h xx  yy  (00h 00h 00h 00h)
  Reply HiZ id  5Ah buttons ( analog-inputs )

The rumble motor is simply controlled by three bits in the xx/yy bytes:

  xx --> must be 40h..7Fh            (ie. bit7=0, bit6=1) ;\switches motor on
  yy --> must be 01h,03h,...,FDh,FFh (ie. bit0=1)         ;/

The motor control is digital on/off (no analog slow/fast), recommended values would be yyxx=0140h=on, and yyxx=0000h=off.
LED state is don't care (rumble works with led OFF, RED, and GREEN). In absence of config commands, the LED can be controlled only manually (via Analog button), the current LED state is implied in the controller "id" byte.
For backwards compatibility, the above old method does also work on SCPH-1200 and SCPH-110 (for controlling the right/small motor), alternately those newer pads can use the config commands (for gaining access to both motors).

When the controller enters configuration mode, the old rumble method is disabled until a hard reset. Unknown if it's possible to re-enable the old rumble method programmatically.

New Method, two motors, with config commands (SCPH-1200, SCPH-110)

For using the new rumble method, one must unlock the new rumble mode, for that purpose Sony has invented a "slightly" overcomplicated protocol with not less than 16 new commands (the rumble relevant commands are 43h and 4Dh, also, command 44h may be useful for activating analog inputs by software, and, once when rumble is unlocked, command 42h is used to control the rumble motors). Anyways, here's the full command set...

Normal Mode

  42h "B" Read Buttons (and analog inputs when in analog mode)
  43h "C" Enter/Exit Configuration Mode (stay normal, or enter)

Configuration Mode

  40h "@" Unknown (response HiZ F3h 5Ah 6x00h)
  41h "A" Unknown (response HiZ F3h 5Ah 6x00h)
  42h "B" Read Buttons AND analog inputs (even when in digital mode)
  43h "C" Enter/Exit Configuration Mode (stay config, or exit)
  44h "D" Set LED State (analog mode on/off)
  45h "E" Get LED State (and whatever other status/version values)
  46h "F" Get Variable Response A (depending on incoming bit)
  47h "G" Get whatever values (response HiZ F3h 5Ah 00h 00h 02h 00h 01h 00h)
  48h "H" Unknown (response HiZ F3h 5Ah 00h 00h 00h 00h 01h 00h)
  49h "I" Unknown (response HiZ F3h 5Ah 6x00h)
  4Ah "J" Unknown (response HiZ F3h 5Ah 6x00h)
  4Bh "K" Unknown (response HiZ F3h 5Ah 6x00h)
  4Ch "L" Get Variable Response B (depending on incoming bit)
  4Dh "M" Unlock Rumble (and select response length)
  4Eh "N" Unknown (response HiZ F3h 5Ah 6x00h)
  4Fh "O" Unknown (response HiZ F3h 5Ah 6x00h)

Normal Mode - Command 42h "B" - Read Buttons (and analog inputs when enabled)

  Send  01h 42h 00h xx  yy  (00h 00h 00h 00h)
  Reply HiZ id  5Ah buttons ( analog-inputs )

The normal read command, see Standard Controller chapter for details on buttons and analog inputs. The xx/yy bytes have effect only if rumble is unlocked; use Command 43h to enter config mode, and Command 4Dh to unlock rumble. Command 4Dh has billions of combinations, among others allowing to unlock only one of the two motors, and to exchange the xx/yy bytes, however, with the default values, xx/yy are assigned like so:

  yy.bit0-7 ---> Left/Large Motor M1 (analog slow/fast) (00h=stop, FFh=fastest)
  xx.bit0   ---> Right/small Motor M2 (digital on/off)  (0=off, 1=on)

The Left/Large motor starts spinning at circa min=50h..60h, and, once when started keeps spinning downto circa min=38h. The exact motor start boundary depends on the current position of the weight (if it's at the "falling" side, then gravity helps starting), and also depends on external movements (eg. it helps if the user or the other rumble motor is shaking the controller), and may also vary from controller to controller, and may also depend on the room temperature, dirty or worn-out mechanics, etc.

Normal Mode - Command 43h "C" - Enter/Exit Configuration Mode

  Send  01h 43h 00h xx  00h (zero padded...)
  Reply HiZ id  5Ah buttons (analog inputs...)

When issuing command 43h from inside normal mode, the response is same as for command 42h (button data) (and analog inputs when in analog mode) (but without M1 and M2 parameters). While in config mode, the ID bytes are always "F3h 5Ah" (instead of the normal analog/digital ID bytes).

Entering configuration mode enables the DualShock rumble method and disables the legacy rumble method. Unknown if it's possible to re-enable the old rumble method programmatically.

  xx=00h Stay in Normal mode
  xx=01h Enter Configuration mode

Config Mode - Command 42h "B" - Read Buttons AND analog inputs

  Send  01h 42h 00h M2  M1  00h 00h 00h 00h
  Reply HiZ F3h 5Ah buttons  analog-inputs

Same as command 42h in normal mode, but with forced analog response (ie. analog inputs and L3/R3 buttons are returned even in Digital Mode with LED=Off).

Config Mode - Command 43h "C" - Enter/Exit Configuration Mode

  Send  01h 43h 00h xx  00h 00h 00h 00h 00h
  Reply HiZ F3h 5Ah 00h 00h 00h 00h 00h 00h

Equivalent to command 43h in normal mode, but returning 00h bytes rather than button data, can be used to return to normal mode.

  xx=00h Enter Normal mode (Exit Configuration mode)
  xx=01h Stay in Configuration mode

Back in normal mode, the rumble motors (if they were enabled) can be controlled with normal command 42h. Some controller revisions will only change config mode state upon receiving the entire command sequence while others will set it immediately on receiving the xx byte. So while aborting the command sequence early (i.e. setting JOY_CTRL to 0 after sending xx, which some homebrew software does) may work for setting config mode state on some controllers, in practice this technique is undefined behavior and use should be avoided.

Config Mode - Command 44h "D" - Set LED State (analog mode on/off)

  Send  01h 44h 00h val sel 00h 00h 00h 00h
  Reply HiZ F3h 5Ah 00h 00h 00h 00h 00h 00h

If "sel=02h", then "val" is applied as new LED state (val=00h for LED off aka Digital mode, and val=01h for LED on/red aka analog mode).

Using this command has a side effect of resetting the DualShock rumble configuration to FFh FFh FFh FFh FFh FFh.

Config Mode - Command 45h "E" - Get LED State (and whatever values)

  Send  01h 45h 00h 00h 00h 00h 00h 00h 00h
  Reply HiZ F3h 5Ah 01h 02h val 02h 01h 00h

Returns val=00h for LED off, and val=01h for LED on/red. The other values might indicate the number of rumble motors, analog inputs, or version information, or so.

Config Mode - Command 46h "F" - Get Variable Response A

  Send  01h 46h 00h xx  00h 00h 00h 00h 00h
  Reply Hiz F3h 5Ah 00h 00h yy  yy  yy  yy

Purpose unknown, but seems to be used by some games to identify the controller as a DualShock Analog Controller since Jogcon returns different values. Response varies: If xx=00h then yy=01h,02h,00h,0ah, else if xx=01h then yy=01h,01h,01h,14h. Other values of xx will cause yy = 00h 00h 00h 00h to be returned. Unknown what happens if the other values after xx are modified, but it is likely that the controller will default to yy = 00h 00h 00h 00h.

Config Mode - Command 47h "G" - Get whatever values

  Send  01h 47h 00h 00h 00h 00h 00h 00h 00h
  Reply HiZ F3h 5Ah 00h 00h 02h 00h 01h 00h

Purpose unknown, but seems to be used by some games to identify the controller as a DualShock Analog Controller since Jogcon returns different values. Modifications to the sequence being sent to the controller seem to cause the controller to respond with 00h 00h 00h 00h 00h 00h.

Config Mode - Command 4Ch "L" - Get Variable Response B

  Send  01h 4Ch 00h xx  00h 00h 00h 00h 00h
  Reply Hiz F3h 5Ah 00h 00h 00h yy  00h 00h

Purpose unknown, but as with 46h and 47h, may be used by some games to identify the controller as a DualShock Analog Controller. Response varies: If xx=00h then yy=04h, else if xx=01h then yy=07h. All other xx values and sequences seem to have a 00h 00h 00h 00h 00h 00h response.

Config Mode - Command 4Dh "M" - Set Rumble Configuration (and select response length)

  Send  01h 4Dh 00h aa  bb  cc  dd  ee  ff
  Reply Hiz F3h 5Ah <-----old values----->

Nocash's original notes state that this command unlocks the rumble motors -- however, based on hardware testing, the DualShock rumble mode is unlocked as soon as a controller enters configuration mode. This command just sets the DualShock rumble configuration.

The rumble configuration works as follows: The last 00h byte in the rumble configuration sequence determines which byte in the 42h pad read command will be used for setting the small motor strength. The last 01h byte in the sequence similarly determines which byte will be used for the large motor strength. If either 00h or 01h or both are not present in the configuration sequence, the corresponding motor will not be able to receive any rumble, as expected.

Most games will use 00h 01h FFh FFh FFh FFh, however a number of games will use uncommon sequences. For example, Final Fantasy VIII uses FFh 00h 01h FFh FFh FFh while Armored Core Project Phantasma uses 00h 00h 01h 01h FFh FFh.

Untested Nocash notes: The extra halfword(s) increase the transfer length by 1 or 2 halfwords (and accordingly, the digital mode ID changes from 41h to 42h or 43h), the controller returns 00h bytes for the extra halfwords, in analog mode, the ID and transfer length remains unchanged (since it always has extra halfwords for analog responses). So, the extra halfwords seem to be output to the controller (rather than response data), possibly intended to control additional rumble motors or to output data to other hardware features.

Config Mode - Command 48h "H" - Unknown (response HiZ F3h 5Ah 4x00h 01h 00h)

  Send  01h 48h 00h 00h 00h 00h 00h 00h 00h
  Reply HiZ F3h 5Ah 00h 00h 00h 00h 01h 00h

This command does return a bunch of 00h bytes, and one 01h byte. Purpose unknown. The command does not seem to be used by any games.

Config Mode - Command 40h "@" - Unknown (response HiZ F3h 5Ah 6x00h)

Config Mode - Command 41h "A" - Unknown (response HiZ F3h 5Ah 6x00h)

Config Mode - Command 49h "I" - Unknown (response HiZ F3h 5Ah 6x00h)

Config Mode - Command 4Ah "J" - Unknown (response HiZ F3h 5Ah 6x00h)

Config Mode - Command 4Bh "K" - Unknown (response HiZ F3h 5Ah 6x00h)

Config Mode - Command 4Eh "N" - Unknown (response HiZ F3h 5Ah 6x00h)

Config Mode - Command 4Fh "O" - Unknown (response HiZ F3h 5Ah 6x00h)

  Send  01h 4xh 00h 00h 00h 00h 00h 00h 00h
  Reply HiZ F3h 5Ah 00h 00h 00h 00h 00h 00h

These commands do return a bunch of 00h bytes. Purpose unknown. These commands do not seem to be used by any games.

Watchdog Timer

Caution: Additionally to activating configuration commands, entering config mode does also activate a Watchdog Timer which does reset the controller if there's been no communication for about 1 second or so. The watchdog timer remains active even when returning to normal mode via Exit Config command. The reset does disable and lock rumble motors, and switches the controller to Digital Mode (with LED=off, and analog inputs disabled). To prevent this, be sure to keep issuing joypad reads even when not needing user input (eg. while loading data from CDROM).
Caution 2: A similar reset occurs when the user pushes the Analog button; this is causing rumble motors to be stopped and locked, and of course, the analog/digital state gets changed.
Caution 3: If config commands were used, and the user does then push the analog button, then the 5Ah-byte gets replaced by 00h (ie. responses change from "HiZ id 5Ah ..." to "HiZ id 00h ...").
Caution 4: Most emulators do not emulate this watchdog functionality so any homebrew with analog pad support should ideally also be tested on hardware to make sure it doesn't accidentally trigger the watchdog

Note

Rumble is a potentially annoying feature, so games that do support rumble should also include an option to disable it.

Controllers - Dance Mats

PSX Dance Mats are essentially normal joypads with uncommonly arranged buttons, the huge mats are meant to be put on the floor, so the user could step on them.

Dance Mat vs Joypad Compatibility

There are some differences to normal joypads: First of, the L1/L2/R1/R2 shoulder buttons are missing in most variants. And, the mats are allowing to push Left+Right and Up+Down at once, combinations that aren't mechanically possible on normal joypads (some dancing games do actually require those combinations, whilst some joypad games may get confused on them).

Dance Mat Unknown Things

Unknown if the mat was sold in japan, and if so, with which SLPH/SCPH number.
Unknown if the mat's middle field is also having a button assigned.
Unknown if the mat is having a special controller ID, or if there are other ways to detect mats (the mats are said to be compatible with skateboard games, so the mats are probably identifying themselves as normal digital joypad; assuming that those skateboard games haven't been specifically designed for mats).

Dance Mat Games

  D.D.R. Dance Dance Revolution 2nd Remix
  (and maybe whatever further games)

The mats can be reportedly also used with whatever skateboard games.

Dance Mat Variants

There is the US version (DDR Dance Pad, SLUH-00071), and a slightly different European version (Official Dance Mat, SLEH-00023: shiny latex style with perverted colors, and Start/Select arranged differently). The japanese version (RU017) resembles the US version, but without Triangle/Square symbols drawn in lower left/right edges.
And there is a handheld version (with additional L1/L2/R2/R1 buttons; maybe unlicensed; produced as MINI DDR, and also as Venom Mini Dance Pad).

   US Version (white/black/red/blue)         Handheld Version (blue/gray)
    __________.---------.___________          _____/ MINI  \_____
   |          \         /           |        |      D.D.R.       |
   |  SELECT   '-------'    START   |        |L1 L2 SEL STA R2 R1|
   |------------.------.------------|        | ___    ___    ___ |
   |  .''''.   /        \   .''''.  |        || X |  | ^ |  | O ||
   | |  \/  | |    /\    | | .''. | |        ||___|  |___|  |___||
   | |  /\  | |   /..\   | | '..' | |        | ___   .---.   ___ |
   |  '....'  '.   ||   .'  '....'  |        || < | |Stay | | > ||
   | .-------. .''''''''. .-------. |        ||___| |Cool!| |___||
   |/   /|   .'          '.   |\   \|        | ___   '___'   ___ |
   |   / |-- |            | --| \   |        || []|  | v |  | /\||
   |   \ |-- | Stay Cool! | --| /   |        ||___|  |___|  |___||
   |\   \|   '.          .'   |/   /|        |___________________|
   | '-------' '........' '-------' |
   |  .''''.  .'   ||   '.  .''''.  |        Gothic Dance Mat (black/silver)
   | |  /\  | |   \''/   | | |''| | |         _.----------._
   | | /__\ | |    \/    | | |..| | |        | \ SEL  STA / | This one
   |  '....'   \        /   '....'  |        |  '--------'  | wasn't ever
   '------------'------'------------'        | .----------. | produced,
                                             | |  .''''.  | | as cool as
   European Version (pink/blue/yellow)       | | |  /\  | | | it could have
    __________.---------.___________         | | | /..\ | | | been, the lame
   |          \ SEL STA /           |        | |  '.||.'  | | marketing
   |           '-------'            |        | +----------+ | people didn't
   |----------.----------.----------|        | |  .''''.  | | even think
   |  .''''.  |  .''''.  |  .''''.  |        | | |  /\  | | | about it.
   | |  \/  | | |  /\  | | | .''. | |        | | | /..\ | | |
   | |  /\  | | | /..\ | | | '..' | |        | |  '.||.'  | |
   |  '....'  |  '.||.'  |  '....'  |        | +----------+ |
   |----------+-..    ..-+----------|        | |  .'||'.  | |
   |  .'/|'.  /   ''''   \  .'|\'.  |        | | | \''/ | | |
   | | / |--|/            \|--| \ | |        | | |  \/  | | |
   | | \ |--|\            /|--| / | |        | |  '....'  | |
   |  '.\|.'  \   ....   /  '.|/.'  |        | +----------+ |
   |----------+-''    ''-+----------|        | |  .'||'.  | |
   |  .''''.  |  .'||'.  |  .''''.  |        | | | \''/ | | |
   | |  /\  | | | \''/ | | | |''| | |        | | |  \/  | | |
   | | /__\ | | |  \/  | | | |..| | |        | |  '....'  | |
   |  '....'  |  '....'  |  '....'  |        | '----------' '
   '----------|----------|----------'        '--------------'

Stay Cool?

Despite of the "Stay Cool!" slogan, the mat wasn't very cool - not at all! It offered only two steps back-and-forth, and also allowed to do extremly uncool side-steps. Not to mention that it would melt when dropping a burning cigarette on it. Stay Away!

Controllers - Pop'n Controllers

Controllers used for Konami's Pop'n Music series. At least a few different versions of the controller (Pop'n Controller, Pop'n Controller 2, larger arcade-size version, possibly others and in different color variations) have been released for the PS1 and PS2. Unknown if the controllers released in the PS2 era have any additional commands not present in the original Pop'n Controller, but they are supposedly fully compatible with PS1 Pop'n Music games.

Pop'n Controllers report as digital controllers (ID byte 41h), but the left, right, and down d-pad controls are not connected to any physical buttons and are always reported as pressed (in the first transferred button byte, bits 5-7 are always 0). Pop'n Music games check these bits to determine if a Pop'n Controller is connected and will change the in-game controls accordingly if so.

Controllers - Densha de Go! / Jet de Go! Controllers

Controllers used for Taito's Densha de Go! and Jet de Go! series. Unknown what method is being used by Densha de Go! and Jet de Go! games for detecting these controllers.

  • The workings of Densha de Go! PSX controllers have been extensively researched in the ddgo-controller-docs repo.
  • The Jet de Go! PSX controller comes in gray and black color. It seems to work the same as an analog controller and supports vibration. The steering wheel is mapped to the left stick (wheel rotation as horizontal, wheel raise/lower as vertical axis). The thrust throttle seems mapped to the right stick Y-axis full range (so half throttle matches vertically centered right stick).

Controllers - Fishing Controllers

The fishing rods are (next to lightguns) some of the more openly martial playstation controllers - using the credo that "as long as you aren't using dynamite: it's okay to kill them cause they don't have any feelings."

PSX Fishing Controller Games

  Action Bass (Syscom Entertainment) (1999) (SLPH-00100)
  Bass Landing (ASCII/agetec) (1999) (SLPH-00100, SLUH-00063)
  Bass Rise, Fishing Freaks (Bandai) (1999) (BANC-0001)
  Bass Rise Plus, Fishing Freaks (Bandai) (2000) (BANC-0001, SLPH-00100)
  Breath of Fire IV (Capcom) (SLUH-00063)
  Championship Bass (EA Sports) (2000) (SLUH-00063)
  Fish On! Bass (Pony Canyon) (1999) (BANC-0001, SLPH-00100)
  Fisherman's Bait 2/Exiting Bass2 - Big Ol'Bass(Konami)(SLPH-00100,SLUH-00063)
  Fishing Club: (series with 3 titles) (have "headset-logo" on back?)
  Lake Masters II (1999) (Dazz/Nexus) (SLPH-00100)
  Lake Masters Pro (1999) (Dazz/Nexus) (BANC-0001, SLPH-00100)
  Let's Go Bassfishing!: Bass Tsuri ni Ikou! (Banpresto) (1999) (SLPH-00100)
  Matsukata Hiroki no World Fishing (BPS The Choice) (1999) (SLPH-00100)
  Murakoshi Seikai-Bakuchou Nihon Rettou (Victor) (SLPH-00100)
  Murakoshi Masami-Bakuchou Nippon Rettou:TsuriConEdition (1999) (SLPH-00100)
  Pakuchikou Seabass Fishing (JP, 03/25/99) (Victor) (SLPH-00100)
  Perfect Fishing: Bass Fishing (2000) (Seta) (yellow/green logo)
  Perfect Fishing: Rock Fishing (2000) (Seta) (yellow/green logo)
  Oyaji no Jikan: Nechan, Tsuri Iku De! (2000) (Visit) (BANC-0001, SLPH-00100)
  Reel Fishing II / Fish Eyes II (2000)(Natsume/Victor)(SLPH-00100, SLUH-00063)
  Simple 1500 Series Vol. 29: The Tsuri (2000) (yellow/green logo)
  Suizokukan Project: Fish Hunter e no Michi (1999)(Teichiku)(SLPH-00100)
  Super Bass Fishing (1999) (King) (BANC-0001, SLPH-00100, yellow/green logo)
  Super Black Bass X2 (2000) (Starfish) (SLPH-00100)
  Tsuwadou Keiryuu Mizuumihen (Best Edition)(2000) (ASCII PS1+PS2 controllers?)
  Tsuwadou Seabass Fishing (PlayStation the Best) (1999) (Oz Club) (SLPH-00100)
  Uki Uki Tsuri Tengoku Nagami/Uokami Densetsu Oe (2000) (Teichiku)(SLPH-00100)
  Umi no Nushi Tsuri-Takarajima ni Mukatte (1999)(Victor)(BANC-0001,SLPH-00100)
  Winning Lure (Hori) (2000) (for Hori HPS-97 controller)  AKA HPS-98 ?

For more see: http://www.gamefaqs.com/ps/list-109 (sports->nature->fishing)

Logos on CD Covers

US Fishing games should have a "SLUH-00063" logo. European Fishing games don't have any fishing logos; apparently fishing controllers haven't been officially released/supported in Europe.
Japanese Fishing games can have a bunch of logos: Usually BANC-0001 or SLPH-00100 (or both).
Moreover, some japanese games have a yellow/green fishing logo with japanese text (found on Perfect Fishing: Bass Fishing, Perfect Fishing: Rock Fishing, Simple 1500 Series Vol. 29: The Tsuri, Super Bass Fishing) (unknown if that logo refer to other special hardware, or if it means the "normal" BANC-0001 or SLPH-00100 controllers.
And Moreover, some japanese games have some sort of "headset" logos with japanese text, these seem to have same meaning as SLPH-00100; as indicated by photos on CD cover of Tsuwadou Keiryuu Mizuumihen (Best Edition) (2000); that CD cover also has a "headset 2" logo, which seems to mean a newer PS2 variant of the SLPH-00100.

PSX Fishing Controllers

  ASCII Tsuricon SLPH-00100 (also marked with a second serial, ASC-0514TR, on the packaging box)
  ASCII Tsuricon 2 ASC-0521TR2 (has a mode switch with 3 settings. "1" is original Tsuricon mode, "2" is Tsuricon 2 mode. Unknown what the unnumbered mode does)
  Sammy Tsuricon 2 SMY-0506FS (looks to be identical to the ASCII Tsuricon 2)
  Sammy Tsuricon 2+ SMY-0511FS (unknown what the differences between this and the Tsuricon 2 are)
  Agetec Bass Landing Fishing Controller SLUH-00063 (US version of ASCII's SLPH-00100 controller)
  Bandai Fishing Controller BANC-0001 (dark gray/blue) (has less buttons than ASCII/agetec)
  Interact Fission (light gray/blue)(similar to ASCII/agetec, 2 extra buttons?)
  Naki (transparent blue) (looks like a clone of the ASCII/agetec controllers)
  Hori Fighting Rod HPS-97/HPS-98 (black/gray) (a fishing rod attached to a plastic fish)

Of these, the ASCII/agetec controllers seem to be most popular (and most commonly supported). The Bandai contoller is also supported by a couple of games (though the Bandai controller itself seems to be quite rare). The Interact/Naki controllers are probably just clones of the ASCII/agetec ones. The Hori controller is quite rare (and with its string and plastic fish, it's apparently working completely different than the other fishing controllers).

Tech Info (all unknown)

Unknown how to detect fishing controllers.
Unknown how to read buttons, joystick, crank, motion sensors.
Unknown how to control rumble/vibration.
Unknown if/how Bandai differs from ASCII/agetec (aside from less buttons).
Unknown how the Hori thing works.

ASCII SLPH-00100 / agetec SLUH-00063 (silver)

          ___
       __|___|__
     _|         |_     _   __
    | |         | |   | |=|__| <--- crank handle
    | | SEL STA | |   | |
    | |         | |---|  \                         ASCII SLPH-00100
    |  \       /  |---|  /                         agetec SLUH-00063
   /  L1       R1  \  | |  __
  |  L2  .---.  R2  | |_|=|__|
  |     | joy |     |
  |     |stick|     |  <------- analog thumb controlled joystick
  | /\   '---'   >< |
  |   []       ()   |
   \     ASCII     /
    '.___________.'   \___ 10 buttons (SEL,STA,L1,L2,R1,R2,/\,[],(),><)
       \ _____ /
        |     |           Note: many (not all) agetec controllers
        |     |           have the >< and () buttons exchanged
        |     |
        |     |              Aside from the crank/buttons/joystick,
        |     |              the controller reportedly contains:
        |     |              some sort of motion sensors?
        |     |              some kind of rumble/vibration?
        |     |
        '.___.'
           '--...___ cable

Bandai BANC-0001 (dark gray/blue)

          ___
       __|___|__
     _|         |      _   __
    | .---.     |\    | |=|__| <--- crank handle
    || joy |    | |   | |
    ||stick|    | |-#-|  \
    | '---'     | |-#-|  /
   / \          |  \  | |  __
  |   |   ...   |   | |_|=|__|
  |   |  :   :  | ()|
  |   |O :___: O|   |   <--- two buttons: () and ><
  |   |- |___| -| ><|        and some slide switch with I and 0 positions?
  |   |         |   |
   \  |  BANDAI |  /      unknown if the joystick is digital or analog
    '._\_______/_.'
       |       |          unknown if there are motion sensors and/or rumble
       '.     .'
        |     |
        |     |
        |     |
        |     |
        |     |
        |     |
        |     |
        '.___.'
           '--...___ cable

Hori HPS-97 / HPS-98 (black/gray)

              ....----------------O
           .''                     \  HPS-97 (controller bundled with game)
          _:_        \              \ HPS-98 (controller only, for HPS-96 game)
       __|___|__      \ short        \
     _|         |_      elastic       \
    |             |     pole           \
    |             |                     \    <--- string (from pole to
    |     SW?     |     _   __           \        reel inside of fish)
   /               \   | |=|__|           \
  |      .---.      |  | |                 \
  | ( ) | joy |     |--|  \                 \               ___
  |     |stick|     |--|  /                  \             /   /
  | ( )  '---'      |  | |  __                \     ...---''''''--.  /|
  |                 |  |_|=|__| <--- crank     \   '               '/ |
   \    ( ) ( )    /                 handle     '..|                  |.
    '.___________.'                                |__________________| :
       \       /     \                                plastic fish      :
        |     |       joystick,                  (presumable some heavy :
        |     |       four buttons,              stationary thing that  :
        |     |       and a switch?              rests on floor)        :
        |     |                                  (presumably with       :
        |     |                                  motor-driven reel?)    :
        |     |                                                         :
        |     |     the two cables do probably connect                  :
        |     |     to both of the PSX controller slots                 :
        '.___.'                                            cable 2  ---'
           '--...___ cable 1

Controllers - Stepper Controller

A controller in the form of a stepper machine. Comes in an orange variant (TW-20001) and a blue variant (TW-20002). Was available for purchase as a standalone controller or as a bundle with Happy Jogging in Hawaii. Requires an analog controller to be connected to the stepper in order to work. The stepper forces the analog controller to switch to analog mode. With some (cheap?) third-party Playstation controllers, this might actually result in permanently activating the controller's rumble. The stepper overwrites the left stick X-axis values with the position of the stepper pedals: - Left stepper pedal fully down equals to left stick fully to left - Right stepper pedal fully down equals to left stick fully to right - Left and right stepper pedal equal height matches left stick horizontally centered Further details unknown.

  Happy Diet (SLPS-03182)
  Happy Jogging in Hawaii (SLPS-03306)
  Tonde! Tonde! Diet Stepper Action Game (SLPS-03347)
  Undou Busoku Kaishou! Punch de Diet (SLPS-03380)
  Chasing de Diet (unreleased)
  Happy Jogging in Paris (unreleased)

Controllers - I-Mode Adaptor (Mobile Internet)

The I-Mode Adaptor cable (SCPH-10180) allows to connect an I-mode compatible mobile phone to the playstation's controller port; granting a mobile internet connection to japanese games.

PSX Games for I-Mode Adaptor (Japan only)

  Doko Demo Issyo (PlayStation the Best release only) (Sony) 2000
  Doko Demo Issyo Deluxe Pack (Bomber eXpress/Sony) 2001
  Hamster Club-I (SLPS-03266) (Jorudan) 2002
  iMode mo Issyo: Dokodemo Issho Tsuika Disc (Bomber/Sony) 2001
  Keitai Eddy (iPC) 2000 (but, phone connects to SIO port on REAR side of PSX?)
  Komocchi (Victor) 2001
  Mobile Tomodachi (Hamster) 2002
  Motto Trump Shiyouyo! i-Mode de Grand Prix (Pure Sound) 2002
  One Piece Mansion (Capcom) 2001 (japanese version only)

The supported games should have a I-Mode adaptor logo on the CD cover (the logo depicts two plugs: the PSX controller plug, and the smaller I-Mode plug).
Note: "Dragon Quest Monsters 1 & 2" was announced/rumoured to support I-mode (however, its CD cover doesn't show any I-Mode adapter logo).

Tech Details (all unknown)

Unknown how to detect the thing, and how to do the actual data transfers.
The cable does contain a 64pin chip, an oscillator, and some smaller components (inside of the PSX controller port connector).

Hardware Variant

Keitai Eddy seems to have the phone connect to the SIO port (on rear side of the PSX, at least it's depicted like so on the CD cover). This is apparently something different than the SCPH-10180 controller-port cable. Unknown what it is exactly - probably some mobile internet connection too, maybe also using I-mode, or maybe some other protocol.

Controllers - Additional Inputs

Reset Button

PSX only (not PSone). Reboots the PSX via /RESET signal. Probably including for forcefully getting through the WHOLE BIOS Intro, making it rather useless/annoying? No idea if it clears ALL memory during reboot?

CDROM Shell Open

Status bit of the CDROM controller. Can be used to sense if the shell is opened (and also memorizes if the shell was opened since last check; allowing to sense possible disk changes).

PocketStation

Memory Card with built-in LCD screen and Buttons (which can be used as miniature handheld console). However, when it is connected to the PSX, the buttons are vanishing in the cartridge slot, so the buttons cannot be used as additional inputs for PSX games.

Serial Port PSX only (not PSone)

With an external adaptor (voltage conversion), the serial port can be used (among others) to connect a RS232 Serial Mouse. Although, most or all commercial games with mouse input are probably (?) supporting only Sony's Mouse (on the controller port) (rather than standard RS232 devices on the serial port).

TTY Debug Terminal

If present, the external DUART can be used for external keyboard input, at the BIOS side, this is supported as "std_in".

Controllers - Misc

Standard Controllers

  SCPH-1010  digital joypad (with short cable)
  SCPH-1080  digital joypad (with longer cable)
  SCPH-1030  mouse (with short cable)
  SCPH-1090  mouse (with longer cable)
  SCPH-1092  mouse (european?)
  SCPH-1110  analog joystick
  SCPH-1150  analog joypad (with one vibration motor, with red/green led)
  SCPH-1180  analog joypad (without vibration motors, with red/green led)
  SCPH-1200  analog joypad (with two vibration motors) (dualshock)
  SCPH-110   analog joypad (with two vibration motors) (dualshock for psone)
  SCPH-10010 dualshock2 (analog buttons, except L3/R3/Start/Select) (for ps2)
  SCPH-1070  multitap

Special Controllers

  SCPH-4010 VPick (guitar-pick controller) (for Quest for Fame, Stolen Song)

BANDAI "BANC-0002" - 4 Buttons (Triangle, Circle, Cross, Square) (nothing more)

SCPH-2000 Keyboard/Mouse adapter

A PS/2 to PSX controller port adaptor, for educational Lightspan titles.
There are two variants of the adaptor:

  Adaptor with short cable to PSX-controller port (and prototype marking)
  Adaptor without cable, directly plugged into controller port (final version?)

Joystick

     __________                     __________
    |          |                   |    ^     |     ^
    | L1    R1 |                   | X <+> O  |    <+> = Digital Stick
     \      ___| <--- L2   [] ---> |___ v    /      v
      |    |     <--- R2   /\ --->     |    |
   ___|    |___________________________|    |___   Not sure if all buttons
  |   |    | SEL STA              =?=  |    |   |  are shown at their
  |   |    |                           |    |   |  correct locations?
  |   |    |_         []   /\         _|    |   |
  |  _|     /    L1             R1    \     |_  |
  |  \_____/          X     O          \_____/  |
  |   /___\      L2             R2      /___\   |
  |                                             |
  |                                             |
   \___________________________________________/
 The thumb buttons on the left act as L1 and R1,
    the trigger is L2, the pinky button is R2
 The thumb buttons on the right act as X and O,
    the trigger is Square and the pinky button is Triangle.
 I find this odd as the triggers should've been L1 and R1,
    the pinkies L2 and R2.
 The buttons are redundantly placed on the base as large buttons like what
    you'd see on a fight/arcade stick. Also with Start and Select.
 There is also a physical analog mode switch,
    not a button like on dual shock.

Memory Card Read/Write Commands

Reading Data from Memory Card

  Send Reply Comment
  81h  N/A   Memory Card Access (unlike 01h=Controller access), dummy response
  52h  FLAG  Send Read Command (ASCII "R"), Receive FLAG Byte
  00h  5Ah   Receive Memory Card ID1
  00h  5Dh   Receive Memory Card ID2
  MSB  (00h) Send Address MSB  ;\sector number (0..3FFh)
  LSB  (pre) Send Address LSB  ;/
  00h  5Ch   Receive Command Acknowledge 1  ;<-- late /ACK after this byte-pair
  00h  5Dh   Receive Command Acknowledge 2
  00h  MSB   Receive Confirmed Address MSB
  00h  LSB   Receive Confirmed Address LSB
  00h  ...   Receive Data Sector (128 bytes)
  00h  CHK   Receive Checksum (MSB xor LSB xor Data bytes)
  00h  47h   Receive Memory End Byte (should be always 47h="G"=Good for Read)

Non-sony cards additionally send eight 5Ch bytes after the end flag.
When sending an invalid sector number, original Sony memory cards respond with FFFFh as Confirmed Address (and do then abort the transfer without sending any data, checksum, or end flag), third-party memory cards typically respond with the sector number ANDed with 3FFh (and transfer the data for that adjusted sector number).

Writing Data to Memory Card

  Send Reply Comment
  81h  N/A   Memory Card Access (unlike 01h=Controller access), dummy response
  57h  FLAG  Send Write Command (ASCII "W"), Receive FLAG Byte
  00h  5Ah   Receive Memory Card ID1
  00h  5Dh   Receive Memory Card ID2
  MSB  (00h) Send Address MSB  ;\sector number (0..3FFh)
  LSB  (pre) Send Address LSB  ;/
  ...  (pre) Send Data Sector (128 bytes)
  CHK  (pre) Send Checksum (MSB xor LSB xor Data bytes)
  00h  5Ch   Receive Command Acknowledge 1
  00h  5Dh   Receive Command Acknowledge 2
  00h  4xh   Receive Memory End Byte (47h=Good, 4Eh=BadChecksum, FFh=BadSector)

Get Memory Card ID Command

  Send Reply Comment
  81h  N/A   Memory Card Access (unlike 01h=Controller access), dummy response
  53h  FLAG  Send Get ID Command (ASCII "S"), Receive FLAG Byte
  00h  5Ah   Receive Memory Card ID1
  00h  5Dh   Receive Memory Card ID2
  00h  5Ch   Receive Command Acknowledge 1
  00h  5Dh   Receive Command Acknowledge 2
  00h  04h   Receive 04h
  00h  00h   Receive 00h
  00h  00h   Receive 00h
  00h  80h   Receive 80h

This command is supported only by original Sony memory cards. Not sure if all sony cards are responding with the same values, and what meaning they have, might be number of sectors (0400h) and sector size (0080h) or whatever.

Invalid Commands

  Send Reply Comment
  81h  N/A   Memory Card Access (unlike 01h=Controller access), dummy response
  xxh  FLAG  Send Invalid Command (anything else than "R", "W", or "S")

Transfer aborts immediately after the faulty command byte, or, occasionally after one more byte (with response FFh to that extra byte).

FLAG Byte

The initial value of the FLAG byte on power-up (and when re-inserting the memory card) is 08h.
Bit3=1 is indicating that the directory wasn't read yet (allowing to sense memory card changes). For some strange reason, bit3 is NOT reset when reading from the card, but rather when writing to it. To reset the flag, games are usually issuing a dummy write to sector number 003Fh, more or less unneccessarily stressing the lifetime of that sector.
Bit2=1 seems to be intended to indicate write errors, however, the write command seems to be always finishing without setting that bit, instead, the error flag may get set on the NEXT command.
Note: Some (not all) non-sony cards also have Bit5 of the FLAG byte set.

Timings

IRQ7 is usually triggered circa 1500 cycles after sending a byte (counted from the begin of the first bit), except, the last byte doesn't trigger IRQ7, and, after the 7th byte of the Read command, an additional delay of circa 31000 cycles occurs before IRQ7 gets triggered (that strange extra delay occurs only on original Sony cards, not on cards from other manufacturers).
There seems to be no extra delays in the Write command, as it seems, the data is written on the fly, and one doesn't need to do any write-busy handling... although, theoretically, the write shouldn't start until verifying the checksum... so it can't be done on the fly at all...?

Notes

Responses in brackets are don't care, (00h) means usually zero, (pre) means usually equal to the previous command byte (eg. the response to LSB is MSB).

Memory cards are reportedly "Flash RAM" which sounds like bullshit, might be battery backed SRAM, or FRAM, or slower EEPROM or FLASH ROM, or vary from card to card...?

Memory Card Data Format

Data Size

  Total Memory 128KB = 131072 bytes = 20000h bytes
  1 Block 8KB = 8192 bytes = 2000h bytes
  1 Frame 128 bytes = 80h bytes

The memory is split into 16 blocks (of 8 Kbytes each), and each block is split into 64 sectors (of 128 bytes each). The first block is used as Directory, the remaining 15 blocks are containing Files, each file can occupy one or more blocks.

Header Frame (Block 0, Frame 0)

  00h-01h Memory Card ID (ASCII "MC")
  02h-7Eh Unused (zero)
  7Fh     Checksum (all above bytes XORed with each other) (usually 0Eh)

Directory Frames (Block 0, Frame 1..15)

  00h-03h Block Allocation State
            00000051h - In use ;first-or-only block of a file
            00000052h - In use ;middle block of a file (if 3 or more blocks)
            00000053h - In use ;last block of a file   (if 2 or more blocks)
            000000A0h - Free   ;freshly formatted
            000000A1h - Free   ;deleted (first-or-only block of file)
            000000A2h - Free   ;deleted (middle block of file)
            000000A3h - Free   ;deleted (last block of file)
  04h-07h Filesize in bytes (2000h..1E000h; in multiples of 8Kbytes)
  08h-09h Pointer to the NEXT block number (minus 1) used by the file
            (ie. 0..14 for Block Number 1..15) (or FFFFh if last-or-only block)
  0Ah-1Eh Filename in ASCII, terminated by 00h (max 20 chars, plus ending 00h)
  1Fh     Zero (unused)
  20h-7Eh Garbage (usually 00h-filled)
  7Fh     Checksum (all above bytes XORed with each other)

Filesize [04h..07h] and Filename [0Ah..1Eh] are stored only in the first directory entry of a file (ie. with State=51h or A1h), other directory entries have that bytes zero-filled.

Filename Notes

The first some letters of the filename should indicate the game to which the file belongs, in case of commercial games this is conventionally done like so: Two character region code:

  "BI"=Japan, "BE"=Europe, "BA"=America

followed by 10 character game code,

  in "AAAA-NNNNN" form     ;for Pocketstation executables replace "-" by "P"

where the "AAAA" part does imply the region too; (SLPS/SCPS=Japan, SLUS/SCUS=America, SLES/SCES=Europe) (SCxS=Made by Sony, SLxS=Licensed by Sony), followed by up to 8 characters,

  "abcdefgh"

(which may identify the file if the game uses multiple files; this part often contains a random string which seems to be allowed to contain any chars in range of 20h..7Fh, of course it shouldn't contain "?" and "*" wildcards).

Broken Sector List (Block 0, Frame 16..35)

  00h-03h Broken Sector Number (Block*64+Frame) (FFFFFFFFh=None)
  04h-7Eh Garbage (usually 00h-filled) (some cards have [08h..09h]=FFFFh)
  7Fh     Checksum (all above bytes XORed with each other)

If Block0/Frame(16+N) indicates that a given sector is broken, then the data for that sector is stored in Block0/Frame(36+N).

Broken Sector Replacement Data (Block 0, Frame 36..55)

  00h-7Fh Data (usually FFh-filled, if there's no broken sector)

Unused Frames (Block 0, Frame 56..62)

  00h-7Fh Unused (usually FFh-filled)

Write Test Frame (Block 0, Frame 63)

Reportedly "write test". Usually same as Block 0 ("MC", 253 zero-bytes, plus checksum 0Eh).

Title Frame (Block 1..15, Frame 0) (in first block of file only)

  00h-01h  ID (ASCII "SC")
  02h      Icon Display Flag
             11h...Icon has 1 frame  (static) (same image shown forever)
             12h...Icon has 2 frames (animated) (changes every 16 PAL frames)
             13h...Icon has 3 frames (animated) (changes every 11 PAL frames)
            Values other than 11h..13h seem to be treated as corrupted file
            (causing the file not to be listed in the bootmenu)
  03h      Block Number (1-15)  "icon block count"  Uh?
                   (usually 01h or 02h... might be block number within
                   files that occupy 2 or more blocks)
                   (actually, that kind of files seem to HAVE title frames
                   in ALL of their blocks; not only in their FIRST block)
                   (at least SOME seem to have such duplicated title frame,
                   but not all?)
  04h-43h  Title in Shift-JIS format (64 bytes = max 32 characters)
  44h-4Fh  Reserved (00h)
  50h-5Fh  Reserved (00h)  ;<-- this region is used for the Pocketstation
  60h-7Fh  Icon 16 Color Palette Data (each entry is 16bit CLUT)

For more info on entries [50h..5Fh], see
Pocketstation File Header/Icons

Icon Frame(s) (Block 1..15, Frame 1..3) (in first block of file only)

  00h-7Fh  Icon Bitmap (16x16 pixels, 4bit color depth)

Note: The icons are shown in the BIOS bootmenu (which appears when starting the PlayStation without a CDROM inserted). The icons are drawn via GP0(2Ch) command, ie. as Textured four-point polygon, opaque, with texture-blending, whereas the 24bit blending color is 808080h (so it's quite the same as raw texture without blending). As semi-transparency is disabled, Palette/CLUT values can be 0000h=FullyTransparent, or 8000h=SolidBlack (the icons are usually shown on a black background, so it doesn't make much of a difference).

Data Frame(s) (Block 1..15, Frame N..63; N=excluding any Title/Icon Frames)

  00h-7Fh  Data

Note: Files that occupy more than one block are having only ONE Title area, and only one Icon area (in the first sector(s) of their first block), the additional blocks are using sectors 0..63 for plain data.

Shift-JIS Character Set (16bit) (used in Title Frames)

Can contain japanese or english text, english characters are encoded like so:

  81h,40h      --> SPC
  81h,43h..97h --> punctuation marks
  82h,4Fh..58h --> "0..9"
  82h,60h..79h --> "A..Z"
  82h,81h..9Ah --> "a..z"

Titles shorter than 32 characters are padded with 00h-bytes.
Note: The titles are \<usually> in 16bit format (even if they consist of raw english text), however, the BIOS memory card manager does also accept 8bit characters 20h..7Fh (so, in the 8bit form, the title could be theoretically up to 64 characters long, but, nethertheless, the BIOS displays only max 32 chars).
For displaying Titles, the BIOS includes a complete Shift-JIS character set,
BIOS Character Sets
Shift-JIS is focused on asian languages, and does NOT include european letters (eg. such with accent marks). Although the non-japanese PSX BIOSes DO include a european character set, the BIOS memory card manager DOESN'T seem to translate any title character codes to that character set region.

Memory Card Images

There are a lot of different ways to get a save from a memory card onto your PC's hard disk, and these ways sometimes involve sticking some additional information into a header at the beginning of the file.

Raw Memory Card Images (without header) (ie. usually 128K in size)

  SmartLink .PSM,
  WinPSM .PS,
  DataDeck .DDF,
  FPSX .MCR,
  ePSXe .MCD...

don't stick any header on the data at all, so you can just read it in and treat it like a raw memory card.

All of these headers contain a signature at the top of the file. The three most common formats and their signatures are:

     Connectix Virtual Game Station format (.MEM): "VgsM", 64 bytes
     PlayStation Magazine format (.PSX): "PSV", 256 bytes

some programs will OMIT any blank or unallocated blocks from the end of the memory card -- if only three save blocks on the card are in use, for example, saving the other twelve is pointless.

Xploder and Action Replay Files (54 byte header)

  00h..14h Filename in ASCII, terminated by 00h (max 20 chars, plus ending 00h)
  15h..35h Title in ASCII, terminated by 00h (max 32 chars, plus ending 00h)
  36h..    File Block(s) (starting with the Title sector)

This format contains only a single file (not a whole memory card). The filename should be the same as used in the Memory Card Directory. The title is more or less don't care; it may be the SHIFT-JIS title from the Title Sector converted to ASCII.

.MCS Files (Single Save Format)

MCS files consist of the 128 byte directory frame for the savefile's first block followed by all of that savefile's blocks in linked list order. When importing this format, the directory frame should be parsed for the save filename and the filesize while other fields should be ignored. The rest of the directory frame fields and any extra directory frames, in the case of multi-block saves, should be reconstructed based on the destination memory card.

.GME Files (usually 20F40h bytes)

InterAct GME format, produced by the DexDrive.

  000h 12   ASCII String "123-456-STD",00h
  00Ch 4    Usually zerofilled (or meaningless garbage in some files)
  010h 5    Always 00h,00h,01h,00h,01h
  015h 16   Copy of Sector 0..15 byte[00h] ;"M", followed by allocation states
  025h 16   Copy of Sector 0..15 byte[08h] ;00h, followed by next block values
  035h 11   Usually zerofilled (or meaningless garbage in some files)
  040h F00h Fifteen Description Strings (each one 100h bytes, padded with 00h)
  F40h 128K Memory Card Image (128K) (unused sectors 00h or FFh filled)

This is a very strange file format, no idea where it comes from. It contains a F40h bytes header (mainly zerofilled), followed by the whole 128K of FLASH memory (mainly zerofilled, too, since it usually contains only a small single executable file).

Memory Card Notes

Sony PSX Memory Cards

Sony has manufactured only 128KByte memory cards for PSX, no bigger/smaller ones.

Sony PS2 Memory Cards

A special case would be PS2 cards, these are bigger, but PS2 cards won't fit into PSX cards slots (unless when cutting an extra notch in the card edge connector), a PSX game played on a PS2 console could theoretically access PS2 cards (if it supports the different directory structure on that cards).

Third Party Cards with bigger capacity

Some third party cards contain larger memory chips, however, the PSX games/kernel are supporting only regular 128Kbyte cards, so the extra memory can be used only by dividing it into several 128Kbyte memory card images.
Selecting a different memory card image can be done by a switch or button on the card, or via joypad key combinations (joypad/card are sharing the same signals, so the card could watch the traffic on joypad bus, provided that the MIPS CPU is actually reading the joypad).

Third Party Cards with bigger capacity and Data Compression

Some cards are additionally using data compression to increase the card capacity, but that techinque is having rather bad reputation and could result in data loss. For example, if a game has allocated four blocks on the memory card, then it'll expect to be able to overwrite that four blocks at any time (without needing to handle "memory card full" errors), however, if the card is full, and if the newly written data has worse compression ratio, then the card will be unable to store the new game position (and may have already overwritten parts of the old game position). As a workaround, such cards may use a LED to warn users when running low on memory (ideally, there should be always at least 128Kbytes of free memory).

Joytech Smart Card Adaptor

The smart card adaptor plugs into memory card slot, and allows to use special credit card-shaped memory cards. There don't seem to be any special features, ie. the hardware setup does just behave like normal PSX memory cards.

Datel VMEM (virtual memory card storage on expansion port)

The Datel/Interact VMEM exists as standalone VMEM cartridge, and some Datel Cheat Devices do also include the VMEM feature. Either way, the VMEM connects to expansion port, and contain some large FLASH memory, for storing multiple memory cards on it. Unknown, how that memory is accessed (maybe it must be copied to a regular memory card, or maybe they've somehow hooked the Kernel (or even the hardware signals?) so that games could directly access the VMEM?

Passwords (instead of Memory Cards)

Some older games are using passwords instead of memory cards to allow the user to continue at certain game positions. That's nice for people without memory card, but unfortunately many of that games are restricted to it - it'd be more user friendly to support both passwords, and, optionally, memory cards.

Yaroze Access Cards (DTL-H3020)

The Yaroze Access Card connects to memory card slot, the card resembles regular memory cards, but it doesn't contain any storage memory. Instead, it does merely support a very basic Access Card detection command:

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  21h  N/A?  Probably replies HighZ (ie. probably reads FFh)?
  53h  0xh?  Replies unknown 8bit value (upper 4bit are known to be zero)?

Ie. when receiving 21h as first byte, it replies by an ACK, and does then output 0xh as response to the next byte.
Without the Access Card, the Yaroze Bootdisc will refuse to work (the disc contains software for transferring data to/from PC, for developing homebrew games).

Pocketstation (Memory Card with built-in LCD screen and buttons)

Pocketstation