MemCARDuino

Arduino PlayStation 1 Memory Card reader

Thanks to:

• Martin Korth of the NO$PSX - documented Memory Card protocol.
• Andrew J McCubbin - documented PS1 SPI interface.

Connecting a Memory Card to Arduino:

Looking at the Memory Card:
_________________
|_ _|_ _ _|_ _ _|
 1 2 3 4 5 6 7 8

1. DATA - Pin 12 on Arduino
2. CMND - Pin 11 on Arduino
3. 7.6V - External 7.6V power (only required for 3rd party cards and knockoffs)
4. GND - GND Pin on Arduino
5. 3.6V - 5V pin with a voltage divider to 3.6V
6. ATT - Pin 10 on Arduino
7. CLK - Pin 13 on Arduino
8. ACK - Pin 2 on Arduino

Reading save from a PC:

To read saves from the Memory Card to your PC use MemcardRex if you are using Windows.
For other operating systems use a provided Python script.
If you are writing your own application the protocol is as follows:

Interfacing with MemCARDuino:

Communication is done at 38400 bps.
To check if the MemCARDuino is connected to the selected COM port send GETID command.
Device should respond with IDENTIFIER.
Optionally you can send a GETVER to get the version of the firmware.

To Read a 128byte frame send a MCR command with MSB byte and LSB byte of the frame you want to read.
MemCARDduino will respond with 128 byte frame data, [MSB xor LSB xor Data] and Memory Card status byte.

To Write a frame send a MCW command with MSB byte and LSB byte, 128 byte data and [MSB xor LSB xor Data].
MemCARDduino will respond with Memory Card status byte.

Checking if Memory Card is connected:

Read a frame from the card and verify the returned status byte.
If it's 0x47 then card is connected. If it's 0xFF card is not connected.

Python interface:

The python script is designed to raw copy the Memory Card data to PC and vice versa.
Note: As ususal, use at your own risk, it might not work out of the box.

Usage

memcarduino.py -p,--port <serial port> , -r,--read <output file> OR -w,--write <input file> OR -f,--format , [-c,--capacity <capacity>] , [-b,--bitrate <bitrate:bps>]

<serial port> accepts COM port names, or for linux, file references (/dev/tty[...] or others)
<output file> read from memory card and save to file
<input file> read from file and write to memory card (accepts both windows and linux file URI's)
<capacyty> sets memory card capacity [blocks] *1 block = 128 B* (default 1024 blocks)
<bitrate> sets bitrate on serial port (default 38400 bps)

This requires a serial port (/dev/ttyACM0 for Arduino uno's, /dev/ttyUSBX for others, COMX for Windows, and various for macOS) it also requires a specific output file. Changing the baudrate isn't recommended, but is available anyway (it does mean changing the Arduino code manually...)

Python TODO:

• Memory Card CRC function
• Read/Write individual saves
• Add a man page for the script
• Refine comments, readme and script