This was in a SCPH-5000, PU-8 -41 board. The chip soldered to the back of the PCB seems to have the original 80-pin mechacon pinout, but I can't see the numbers on it because someone has taken a milling cutter to the top of the chip. When you boot the machine, it looks like a debug - there is no "SCEI" under the Licensed by text. It also boots anti-mod games without problems. The only strange thing is that it still has the stock SCPH-5000 BIOS and hence can only boot Japanese discs. First time I've ever seen one of these...
I think they changed over to the PU-18 with the SCPH-5500 for the Japanese market. I have 2 SCPH-5000's here, and they both have PU-8 boards in them (they are also both -41 versions). My guess is that someone got the mechacon chip out of a debug, decapped it, extracted the code and then got some of them made - the intentional damage to the top of the chip was presumably to remove the mask ID and lot number so that Sony couldn't go back to the chip maker and find out who ordered them. I'm just rather surprised that after going to all that effort they aren't more common.
Difficult to get a good photo because I don't want to over stress that flex PCB, but this should give you the idea
I was thinking about the same sort of thing back in the day, too - I just didn't realize that anyone had actually done it. All the date codes on the chips in that PSX are mid '96, so I guess the mod was done about 15 years ago, and it's surprising that they are apparently so uncommon that I had never seen (or even heard of) it before.
What else would you call it? "Replacement mechacon that will run copies" is a bit long, even if arguably more accurate.
That's really fascinating. It's too poorly made to be an official repair part. Yet it replaces a complete chip. I am guessing it is a 3rd party refurbishment.
I was trying to keep the title short Anyway, I just removed the FPC from the board (it was pretty fragile, too), so here is a better photo. The chip on the left is an original Sony mechacon from a PU-7 board. The encapsulation looks very similar based on the shape and size / style of the ejector marks. Have you got any idea what the chip is? I always thought that the PSX used a 68HC05 in that position, but that chip really doesn't look like a Motorola part - some part of my brain is going "Hitachi", but I'm not sure why...
The strange thing is that the 5000 came out way after the early mod chips,and the 4 pin pic chips were out by then. If it was a repair, they would desolder the chip / replace so it's not a repair.... The chip looks sort of like a blue debug preproduction chip... anyone care to compare?
My guess is that it's a clone of the mechacon from the old DTL-H100x series debug consoles that used a PU-7 board, and was originally just soldered on the board in place of the retail chip - and when Sony changed the device from an 80 pin one to 52 pins early in the PU-8 production run they still had a whole bunch of the chips left over. Rather than scrap them, they made that adapter board so they could use up their remaining stock.
It's possible that Sony needed some debug consoles and had some original subcpu but only the new motherboards. I heard they pulled retail units and modded them, this could be what they did to them. It would be interesting to get decapped and imaged.
I think this must have made by a third party - they clearly went to some length to destroy the numbers on the chip, and I can't see any possible reason that Sony would want or need to do that. On top of this, Sony certainly had debug mechacon chips in that 52-pin format And that was on a -23 PU-8 board that was quite a bit older than the one that had this mod atached to it.
PU-7 used Hitachi MCUs as Mechacon. PU-8 had two types, the early one would use something custom which was somewhat still compatible with the Hitachi MCU pinout wise, but would not look the same ... Maybe something from Toshiba ... Well, later on they switched to this 52 pin MCU type which I believe be a Motorola 68HC08 kind. Also they switched the boot rom to 8 bit chip with a smaller pin count, stopped using the 160 pin GPU which used dual ported RAM in favor of the new 208 pin GPU chip using SGRAM. Thanks for sharing this with us TriMesh !
