The PSIO is another seemingly “hard to get” mod device for the original Playstation. I actually waited and missed out on this device twice before finding a eBay auction for one and got it for the same price a new one goes for. It was actually new in box.
So what is this madness?
The PSIO is a development device that plugs into the early model Playstation parallel I/O port. The PSIO supports BIN, ISO and IMG files. It has a slick menu system with cover artwork and multiple CD game support.
In order for the PSIO to work properly, you need to install a switch board. This board is needed to switch the signal from the CD-ROM to the development device. 9 wires later… put it back together and see if we still get video.
I put the Cybdyn sticker on the bottom of the PS so I remember that this is the unit that has the PSIO Switch BOard installed.