Nocash, it could be some other *very early* sector as well. But I remember reading somewhere that the wobble starts at sector 4. It is indeed close enough to the POS0 sensor that it sometimes triggers it without any tape added. But it's not reliably doing it. I've verified that adding the tape makes...

I haven't begun to dig into the logic this controller does, but from afar, it looks like a housekeeping chip. It'll manage the read head position, interpret the occasional seek request, spin up and down the disc motor and such things. I'm fairly sure it doesn't have to be in 68000 ASM, nor does it h...

That's true until you start Dino Crisis :) As an old readme from the 90s said, the game is a deliberate attack on (then) stealth modchips (that used a signal to detect the pad init function, normally triggered when the game exe loaded). It boots as normal, but then does an additional check that cons...

So about the stealth: We know that the SCEX string can only be found on the earliest sectors on the CD. The read head has to be at almost the innermost position for reading it. There's a small pin on the read head that signals when it reached the innermost position. One simple method to implement st...

The unlock code is very small. If the UniRom UI loads (tons of code + data), then you can be sure that the unlock code (like 3 simple ASM commands) is getting sent and that it is correct. - Make sure you use a supported console: It has to be an NTSC-U or PAL unit. NTSC-J does not work. - Try differe...

Update: Latest version is here . PSNee is an open source PSX modchip code for Atmel AVR microprocessors like the ATTiny and ATmega (Arduino boards). It was coded by "THE FRIENDLY FRIETMAN" and released on the assemblergames.com forums a while back. Right now, assemblergames is down and PSN...

It's definitely down to marketing and copy protection on PSX.

Well, maybe this should be done on an Arduinio then!
Bypassing any need for modchips is nice, but I'm also interested in optimizing the disk access strategies for modern CD-R media (with their 80 minute playtime).

The laser assemblies are not manufactured anymore. You can buy "new" (old stock) assemblies from various sellers on Ebay though. For PU-8 boards, it's common and recommended to use a BAM assembly sourced from a PSone unit. They fit the PU-8 cases perfectly, once the grey top is replaced wi...

ver: 3.0j
crc32: FF3EEB8C
pins: 32pin
chip name: "[SONY], 1030"
mechacon: C 1030, SC430925PB
board name: PU-18 1-664-537-31
console: SCPH-5500
notes: single EDO RAM Chip (IC106), 4 ferrite beads on disc motor lines