Build a USB to Serial cable to communicate with the Playstation
This cable connects a PSX to a computer. If you combine this with a cart flashed with unirom, you can interract with the PSX from your computer, upload executables, access the console's memory...
What you can use :
- An FTDI FT232RL module OR
- An Arduino Uno that supports 3.3V serial OR
- A Raspberry Pi 0,1,2,3,4 OR
- A Raspberry Pi Pico OR
- A CP2102 or CP2104
If you have these stuff lying around, this can help :
- A PSX SCPH-1040 serial cable, or half a cable
- A dead PSX motherboard that has a serial port, or just the SIO socket
- Dupont wires
You only need 3 wires from the PSX : Tx, Rx and Gnd.
PSX pins | FTDI pins 2 | GND 8 | TX 5 | RX
Which controller can be used
Connect PSX SIO pins 2, 5, 8 to the FTDI's Tx, Rx and Gnd. Done.
3.3V Arduino Uno
Some arduino unos have a jumper to use 3.3V instead of 5V levels. You can use such a board with an addintional resistor, like so :
Either over your local network or via a direct lan cable setup, you can use a rpi if you have one lying around.
Plug the PSX's serial output Rx/TX/Gnd to the GPIO14/pin 8 (Tx), GPIO15/pin 10 (Rx) and pin 6 (Gnd).
Raspberry Pi Pico
The new controller by Rpi foundation can be used with the Pico-uart-bridge firmware :
Use GPO 0/Pin 1 as Tx, GPO 1/Pin 2 as Rx and GPO 3/Pin 3 as Gnd :
CP2102 / CP2104
The CP2102 and CP2104 are reported to work at least in /slow mode (115200 bauds).
- CH341 is reported to work in /slow mode (115200 bauds)
From the PSX to the controller
Method #1 : Half SCPH-1040 cable
Hack the cable, connect things and voila :
Method #2 : Salvaged PSX serial port + full SCPH-1040 cable
Use a salvaged PSX SIO port from a dead motherboard, and use your precious serial cable without destroying anything :
Method #3 : Dead or spare PSX motherboard + full SCPH-1040 cable
Same as above except you don't even have to hack the SIO port off the motherboard, just solder your wires directly underneath the SIO port.
Sources : https://thp.io/2020/psxserial.html
Notes & Sources
Port série pinout :
Méthode 3 :
Méthode 4 : http://www.psxdev.net/forum/viewtopic.php?f=47&t=760&p=19081