Weird issue with a 6128+ - Is it ram or ASIC.... ?

[lordheavy]

Bought some month ago a 6128+, with a keyboard repeat problem - that i fixed with separating the two membranes and cleaning them. I thought that all was fine now.

Recently i got an usifac 2, and when i try to use it, i have regular error like basic errors when trying some commands, sometimes a prompt to press return (like if i added a tape reader). I tried various firmware without much success, checked continuity of tracks to cpu and asic.

I noticed another problem, i can't load some games like Rtype128, rick128+, renegade,... but some games that should use extra memory work fine - like the pawn.

I tested the ram with amstrad diagnostics 1.3a and no errors - 69 times with the soak test. I plan to change the ram and see what will happen. Other ideas ?

Thanks !

[eto]

If you do have these problems only with the USIFAC, then probably the USIFAC is related to the problem. 

[lordheavy]

If you do have these problems only with the USIFAC, then probably the USIFAC is related to the problem.

I have problems with games without the usifac interface. I tried cpm+ too and it stops before the prompt.

[eto]

Some games are not compatible with the Plus and need to be patched. Without a patch, keyboard will not work. Elite is an example where this happens. Afaik you also need a Plus version of CP/M. 

What cartridge do you use to boot the Plus? Which software exactly (from which source) does cause the problems and how do you load it? From disc or from USIFAC?

[Bryce]

Sounds like you just need to clean the cartridge port pins.

Bryce.

[lordheavy]

First i must apologyze, my explanations are not clear.

I have two problems, one with an usifac 2, but let's forget about this one.

The second one - with the usifac unplugged, and with an external gotek (zaxon's model): when i try to run 128k games (i just tried dragon ninja, baby joe, robocop, rtype 128k, rick dangerous 128, renegade) games are freezing during loading - it doesn't go most of the time beyong loading screen. All seems fine with 64k games i tested (doppleganger, bruce lee, burnin rubber). So i used amsdiag 1.3a and no problems were detected on rams

I wrote about usifac because i think (probably i'm wrong) that the two problems could be connected - because it copies data in ram. Also i don't have another cpc to test it - so it's a bit on stanby.

@Bryce i checked again and cleaned contacts - no changes.
@eto i use burnin rubber + amsdos rom (blue one) - i don't have any c4cpc cartridge

Thanks for your help

[Cwiiis]

The usifac2 has known issues with Plus machines. As for the ram, best to run a diagnostic rom or program and find out. I use the one that was included in the C4CPC, but I presume one must exist that runs off a disk.

[eto]

I would be surprised if there are RAM faults that prevent 128K games from running, but the diagnostics tool won't catch those faults. 

Just to be sure with Amsdiag you mean this one: https://github.com/llopis/amstrad-diagnostics/releases
If yes, then make sure it reports 128K RAM, C3 support and you can successfully run both the lower and the upper RAM test.

Maybe you can take pictures of you set-up and what you are doing. That sometimes helps to spot an issue that was not in the text. 

Have you tried a demo that requires 128K?

[lordheavy]

I would be surprised if there are RAM faults that prevent 128K games from running, but the diagnostics tool won't catch those faults.

Just to be sure with Amsdiag you mean this one: https://github.com/llopis/amstrad-diagnostics/releases
If yes, then make sure it reports 128K RAM, C3 support and you can successfully run both the lower and the upper RAM test.

Maybe you can take pictures of you set-up and what you are doing. That sometimes helps to spot an issue that was not in the text.

Have you tried a demo that requires 128K?

Yes, it's this one. I tried some demos with the same result - it stops loading - we can say it freezes.

[lordheavy]

Ok, so i fixed the issue ........

I updated the zaxxon's gotek firmware. It was at V3.34, i updated it to v3.36 - then issue with 128k apps is fixed.

Thanks for your help