The PSIO development cartridge, that I had preordered in June 2017, finally arrived this month. The whole package is very well made and looks almost like a genuine Sony PlayStation peripheral. The cartridge requires a modification before use, the PSIO switch board installation. The switch board detects the presence of the cartridge and switches the signals from the ODD to the parallel port.
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The package contains the PSIO cartridge, a quick start guide, the switch board, some wire and a sticker.
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I’m going to install the switch board into my SCPH-5552 PlayStation that I bought years ago with a custom blue case.
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Installation instructions can be downloaded from the PSIO downloads page. There are instructions for 5 different mainboard revisions. The SCPH-5552 model has the PU-18 mainboard built-in, according to this list. Let’s open it up and check if this is true – you never know when dealing with a unit that has been put into a custom case.
Disassembly
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Yes, it’s really a PU-18 mainboard:
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On the bottom side of the PCB there is a weird old modchip installation.
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Installation
I covered the modchip with some tape for now, as it worked flawlessly so far, and went right for the switch board installation.
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The installation manual warns about running wires over the ground contacts (circled), well, the same goes for the Kapton tape.
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Before reassembling the console I tested the installation with the PSIO cartridge plugged in. It worked on the first attempt.
Some final touches: freeing the ground contacts and tidying up the modchip wiring with the leftover wire.
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Ready to play!
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