Table of Contents
- MCU currently supported.
- The oversimplified way to do it
- Find out if my console needs a BIOS patch
- You can use USB injection in the following cases
- Tutorial for injections via USB
- You are required to use ISP injection in the following cases
- Personal recipe to make a good PSNee via ISP
- Pinout MCU & Arduino
- Motherboard diagram
- BIOS diagram
- Other diagrams
- PsNee modchip drawbacks
- PsNee modchip advantages
- PsNee modchip source code
- PAL and NTSC incompatibility with your TV
- Japanese consoles and video glitches with PAL games
- Things just for curiosity
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MCU currently supported.
| MCU | Arduino |
|---|---|
| ATmega328/168 | Uno/Mini/Mini Pro |
| ATmega32u4 | Leonardo/Micro/Micro Pro |
| ATtiny25/45/85* |
*Not compatible with the BIOS patch
The oversimplified way to do it
• Choosing your compilation options.
• Compilation.
• Configure fuses.
| MCU family | High | Low | Extended |
|---|---|---|---|
| ATmega 328/168 | DF | EE | FD |
| ATmega 32u4 | DF | EE | FB |
| ATmega 328PB* | DF | EE | F5 |
| ATtiny 25/45/85 | DD | E2 | FF |
*Not recommended: Chinese Nano v3 Atmega328pb blue cards (clocking problem).
• Injecting the code into the target.
• Soldering the modchip according to the diagrams.
Find out if my console needs a BIOS patch
- When a BIOS patch is needed: All Japanese consoles, and the European SCPH-102 console (PS One).
- Consoles that don't need the BIOS patch: All American consoles, all fat European consoles, and all SCPH-xxx3 models.
You can use USB injection in the following cases
- All consoles that do not require a biopatch.
• All American models SCPH-xxx1
• All Asian models SCPH-xxx3
• Fat European models SCPH-1002 -> 9002 - If you are using an Arduino board with a bootloader.
Tutorial for injections via USB
You are required to use ISP injection in the following cases
- When using ATtiny chips.
- If your console requires a BIOS patch.
• All Japanese models SCPH-xxx0
• The European One SCPH-102
Personal recipe to make a good PSNee via ISP
Pinout MCU & Arduino
- Pinout ATtiny25/45/85
- Pinout Arduino Nano
- Pinout Arduino Micro
- Pinout Arduino Pro Micro
- Pinout Arduino Pro Mini
Motherboard diagram
- PU‐7 diagram
- PU‐8 diagram
- PU‐16 diagram
- PU‐18 diagram
- PU‐20 diagram
- PU‐22 diagram
- PU‐23 diagram
- PM‐41 diagram
- PM‐41 (2) diagram
BIOS diagram
To determine your BIOS version, which is essential for old Japanese models, the BIOS dumper project works very well.
- BIOS V1.0j V1.1j 40PIN
- BIOS V1.0j V1.1j 32PIN
- BIOS V2.2j 40PIN
- BIOS V2.2j V3.0j 32PIN
- BIOS V4.0j -> 4.5e 32PIN
Other diagrams
PsNee modchip drawbacks
Due to the extensive coverage of different PS1 models, there is no universal compilation.
PsNee modchip advantages
The greatest strength of the PsNee modchip is that it is much more modern than PIC-based modchips and supports all PS1 models. Using AVR chips makes programming a PsNee chip easier, and many people may already have an Arduino that can be used as a PsNee modchip. Using more powerful processors allows the modchip to work with American, European, and Japanese PlayStation 1 consoles with a single chip. It can even patch the BIOS. Note that this BIOS patch does not work with ATtiny chips.
PsNee modchip source code
It supports the following microcontrollers:These chips fall into two categories, ATmega based chips, and ATtiny based chips. ATmega chips cost more, but allow for BIOS patching. ATtiny chips cost less. ATmega chips are also considerably larger in size, making them more difficult to fit into a system when compared to the ATtiny chips.
PAL and NTSC incompatibility with your TV
In North America, we have NTSC-U/C consoles and TVs, and in Japan, there are NTSC-J consoles and TVs. Meanwhile, Europe and some other regions use PAL consoles and TVs. On the PlayStation 1, the modchip unlocks the ability to output video for any region based on the game being played. However, not all TVs support all video formats. For example, if you insert a PAL game into your modded system and try to play it on an American TV, you might not get any video output.
To avoid this issue, I recommend buying a cheap composite-to-HDMI converter. These devices convert the unusual analog signal from a game of another region into a standard HDMI signal, ensuring compatibility with your TV.
Japanese consoles and video glitches with PAL games
Japanese consoles with specific clock signals can produce a bad video signal when playing PAL games. A known solution.