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Mystic_Merlin · Joined: 15 Oct 2007 Posts: 496 Location: Bangkok

Guess what I found out of a pile of junk this time?
A good old supercom pro (sp3200), this used to be my 1st copier back in the days so I was pretty excited to get its sexy blue screen up and running...well...not so fast...

The poor beast was in a pretty bad shape when I got it so I wasn't expecting much...moreover when I opened the case...

First time I switched it on I had nothing...then I put a cart and got a black screen. After a bit of cleaning and scratching I finally got the blue screen!

- It does display 8M of ram but 0M for the inserted cart.
- When I click play game card I get a NO CARD.
- I can send files from Ucon64 but I get a black screen (I tried only LoRom files). The only "successful" file I loaded was Tomy's BIOS2SRAM but it displayed lots of garbage around the "RESET THE MACHINE..."
- I switched the ram board with a 16M but same deal

It looks badly corroded, but apart from some of the tracks around the battery, continuity tests seemed to work fine.

1) Any idea, advice or test I could run?

2) I'm mostly interested in getting some small roms loaded via Ucon so no big deal if the FDC part is not working. But I'm curious: by tracking down the J4 to DB25 connections, can I determine the proper pinouts to make a custom DB25 to floppy drive connector, just need to add an external +5V DC, right?

Also I wonder if the modification with the PAL chip added to the bottom part of the Supercom was made to load HiRom on this machine?

PS: That night I also got a SPF 16 that literally blew with smoke coming out of the cart port but that's another story... Laughing

CrackLtd · Joined: 05 Feb 2007 Posts: 239

The Supercom basically is identical to the Super Magicom. It just had a different cover (a flat top). What really is interesting is the modification wich can be seen in the last picture. I am pretty sure that this is a so called 'HiRom Fix'. Is it possible to know wich logic chip that is? Maybe i can mod then my Magicom too. Also check the pcb very carefully. I remember you had to cut one or two traces on the pcb in order to make the HiRom Fix work. I did those mods myself back in the 90ies, but i lost all information on that...

Mystic_Merlin · Joined: 15 Oct 2007 Posts: 496 Location: Bangkok

kyuusaku · Joined: 26 Jul 2003 Posts: 941 Location: .ma.us

Pin 26 is /RESET, you're looking at a bad/old pinout and the wrong side.

I think I have them right:

Mystic_Merlin · Joined: 15 Oct 2007 Posts: 496 Location: Bangkok

kyuusaku · Joined: 26 Jul 2003 Posts: 941 Location: .ma.us

Is pin 16 broken off?

Mystic_Merlin · Joined: 15 Oct 2007 Posts: 496 Location: Bangkok

kyuusaku · Joined: 26 Jul 2003 Posts: 941 Location: .ma.us

Mystic_Merlin · Joined: 15 Oct 2007 Posts: 496 Location: Bangkok

kyuusaku · Joined: 26 Jul 2003 Posts: 941 Location: .ma.us

Mystic_Merlin · Joined: 15 Oct 2007 Posts: 496 Location: Bangkok

kyuusaku · Joined: 26 Jul 2003 Posts: 941 Location: .ma.us

It's a 100% match with mine, so HiROM support must be partially built in or it needs a HiROM "loader" ROM or there's something I'm missing entirely.

Mystic_Merlin · Joined: 15 Oct 2007 Posts: 496 Location: Bangkok

There's some progress! Err...kind of...

Fix something and another problem arrose...

I found out there was 2-3 traces near the cartridge port on the top layer that had tiny cuts. Tracing those were all the more difficult they were going below the ALTERA socket. Also, I had to cut loose the Hirom PAL on the way... Crying or Very sad

Here's what it looks like:

Anyway, now the cartridge is being identified, PLAY CARD works fine.
Only problem is that sending by Ucon does not work anymore (it worked before)... The copier freezes (can't browse through menu) and Ucon reacts as if it was not connected.
I guess I'm not finished tracing but any lead to diagnose the problem would be appreciated Wink

rodneyk · Joined: 29 May 2009 Posts: 15

hi Mystic_Merlin,

I bought a supercom off Ebay a while ago and had a similar experience after opening it... I found a lot of damage to the PCB just like you found.

I am not saying your approach is wrong or anything but if I were in your situation I would handle things a bit differently.

I would document the modifications for highrom carefully and then remove them entirely. I would then document and undo any other modifications and severed connections that were done to the PCB that are not factory defaults, then clean the whole thing carefully. After that I would try to get it to work properly. Since the modifications are not factory made you can't know what the effects will be of them being in place, or if they are even working properly at all. After you get the supercom to work in its original state you can still restore the modifications later if you want.

About properly cleaning off the chemicals that spilled: what I did is I desoldered the entire PCB, cleaned it with vinegar and a sponge used for cleaning pans(soft one, not metal). You do have to watch out not to scrub too hard, only just hard enough to only remove the chemical spills from the surface. What you want is clean copper traces and clean PCB in those areas where the chemical stuff spilled. Only then you can be sure it is all gone without a trace and won't corrode any further. Otherwise corroding will slowly continue still and it could cause future malfunctions. I read that in many fora discussing similar problems. After cleaning you should wash the PCB with soap, then rinse very thoroughly with water and a soft brush and dry it off carefully, be sure to take enough time.

You don't have to desolder everything like I did but if I were you I would at least make sure that the chemicals are cleaned off completely and then after carefully documenting the modifications first try to work from the original supercom layout and connections. At least that way you can be sure you are not overlooking anything.

You can use a continuity test to check all connections if they are intact. If you want to know where any specific connections go let me know, I can help you with that.

Of course, everything you do is at your own risk, use your own judgement and care. I can't judge what level your electronics skill is. Smile

The real technology in your supercom that can't be replaced lies in the EP1810LC. The rest can be replaced and repaired.

By the way, if anyone knows the highrom modification and the programming data of the PAL chip I would appreciate it if it could be posted here. I am also going to examine a Super Wild Card and knowing these highrom modifications might help me in understanding it.

kyuusaku · Joined: 26 Jul 2003 Posts: 941 Location: .ma.us

I've been thinking a bit about the HiROM switch and I have the logic down, but there's one really big problem: hardware alone can't quite automagically detect HiROM and LoROM. It can almost be detected thanks to how predictably HiROM games access memory, but when the game is first loaded as LoROM, the hardware can't tell. The reason is that the CPU reset vector is at $00FFFC, which is located at different physical ROM addresses between Lo/HiROM ($7FFC and $FFFC respectively). Unless the user presses reset to manually switch to HiROM (would be annoying since it'd affect loading/resetting games too and probably corrupt save games), or HiROM games are hacked with LoROM vectors, or the user runs a HiROM "loader" ROM which jumps to the correct address (hopefully in the "HiROM area"), the mod is useless. If you want to put a toggle switch (or few for SRAM limiting) on any LoROM copier though, I know exactly what to do...