Towards the end of the SCPH-10x PSone production Sony revised the board slightly and released the PM-41 (2) board. This page covers the installation diagram for installing an MM3 chip into the PM-41 (2).
If your board has PM-41 printed on it then you should follow the PM-41 guide instead.
The first time I modded a PM-41 (2) I wasn’t able to find an installation diagram, but was able to figure out how everything should be wired through a combination of trial and error, and the diagram for the original PM-41 board.
PM-41 (2) MM3 modchip installation diagram
Above is the installation diagram. It’s labeled as being fore the PIC12F629, but it also works with the PIC12C508A. The difference is that the 12F chip runs better at 5V, which is why the first pin is wired to the voltage regulator. If you have a 12C you could wire the first pin to the pad above the capacitor to the right of the fourth pin (the big pad to the right of that CD holder peg).
Since the diagram isn’t the clearest I’d like to mention that the second pin connects to the right most pin on the top row of pins on the chip.
Here are some tips I have for you when you are soldering your chip into the PM-41 (2).
- Pin 3, and 6 can be tricky. Don’t push on the components with your soldering iron or they might get knocked off the board. You can use tweezers to carefully solder them back on one side at a time, the orientation doesn’t matter.
- Make sure the wire on pin 3 and 6 don’t come into contact with both sides of the component (this is especially common if you run the wire directly on top of the component).
- Don’t apply too much solder to pin 2 or you’ll bridge the pins on the chip.
- Placing the chip directly on top of the shorter large chip (where it is in the diagram) seems to be the ideal location.
Diagram success rate
Here’s a list of people who have successfully modded their console with this diagram. Leave a comment and I’ll add you to the list.
- William Quade (me) (I’ve used this diagram many times and haven’t had any problems with it)