In-Game Reset mod for PlayStation 1 and PSone (aka Slim, yes, Slim model has reset point). Based on Arduino compatible boards. Arduino Pro Mini (ATmega328 or ATmega168) is recommended.

However, this project is obsolete, recommend using the ps1-igr-mfo mod, based on RP2040 (Pico, Zero, Tiny).

In-game reset using player one controller:

• SELECT + START + L1 + R1 or SELECT + START + L2 + R2 - Reset
• SELECT + CROSS + L1 + R1 or SELECT + CROSS + L2 + R2 - Long Reset (useful for X-Station only)

Arduino Nano: connect to PC using USB cable. Arduino Pro Mini: use USB-UART module (e.g. CP2102 board with microUSB or Type-C), connect pins GND-GND, VCC-VCC, DTR-DTR, Tx-Rx, Rx-Tx, then connect module to PC using USB cable.

Using Arduino IDE:
Open ps1-reset-mod.ino in Arduino IDE, select the appropriate Arduino Board type, select the appropriate COM port, then click Upload button.

Using avr-toolchain:
Run make command in terminal, or run build_atmega328.cmd or build_atmega168.cmd command batch file.
Then flash the hex file to Arduino Board using avrdude tool:

avrdude -p atmega328 -c arduino -P COM3 -b 115200 -D -U flash:w:ps1-reset-mod.hex:i

or

avrdude -p atmega168 -c arduino -P COM3 -b 115200 -D -U flash:w:ps1-reset-mod.hex:i

COM port number may be different on your system.
Also COM port baudrate may vary depending of Arduino Board you using.

• ATmega328/ATmega168 optiboot bootloader: 115200
• ATmega328 old bootloader: 57600
• ATmega168 old bootloader: 19200

Program behavior can be configured by defines that can be found in main.c file:

• LONG_RESET_ENABLED - Long reset feature is enabled
• USE_INTERRUPTS - Use interrupts for read controller data, instead of pure polling

Here is a simplest connection pinout Arduino board to PlayStation board:

More pinouts can be found inside guide directory.