PSIO SIO-X switchboard redone in kicad. Not 100% sure this is correct yet. Credit to Voultar for original basic design.
I'm using this successfully in my PS1 (SCPH-1001) for PSIO, mod chip stuff (left half of the board) is untested.
U1 has to be manually rotated (for now) if you print this through JLCPCB. Indicator dot should be in the top left. Mod chip is not included but socket is available as in the original SIO-X.