This is my favorite version of the PlayStation 1. It's in newer systems, so the lasers are more likely to still be in good condition, but the system still has both the serial and parallel ports on the back. This board was used primarily with the SCPH-7500 series of systems.
I sell PsNee modchips in my store.
PU-22 PsNee modchip installation diagram
- Pin VCC - VCC
- Pin GND - GND
- Pin 3 - Debug TX
- Pin 4 - BIOS A18
- Pin 5 - BIOS D2
- Pin 6 - SQCK
- Pin 7 - SUBQ
- Pin 8 - DATA
- Pin 9 - GATE_WFCK
Above is the diagram for the PU-22.
This diagram is fairly straightforward. Be careful when soldering to the capacitor that connects to VCC and GND. In particular, the GND point can easily be bridged to nearby pins/pads.
Here are some tips I have for you when you are soldering your chip into the PU-22.
- Cut your wires to be as short and direct as possible.
- You don't need to connect pins one and two of the ATtinyX5 chip. Just desolder the wire.
- Use a multimeter to probe around for alternative VCC and GND points closer to where you position your chip for a cleaner installation.
- Placing the chip on top of the chip in between SUBQ, SQCK, GND, and VCC is a good spot.
- Watch out for solder splatter when you are desoldering the metal shield on top of the board. It isn't necessary to put it back on, but I always do.
This section has photos of some successful installations which you can use to get a better understanding of how everything is wired and positioned.
- Jon Co