terriblefire wrote: ↑Sun Sep 16, 2018 12:05 pm The Diagnosis cart is a toy for checking if something subtle is happening in on of the chips. DiagROM will help you find data bus shorts when building a machine.
I don't tend to use the cart much at all.. it can test a lot of things, but for me its pointless. I mean I know if the keyboard isn't working, I don't need the cart to tell me that. Over serial on a faulty machine, I only saw garbage output, if the system is working fine, then the serial is fine, but again, unless the machine is partly working its just useless for me.
czietz wrote a really good RAM test program https://www.exxosforum.co.uk/forum/viewt ... ?f=25&t=28 as the atari-cart wasn't finding some very subtle errors. So that one is more in-depth tests and finds such faults. But of course the machine has to be partly working to load it up. I'm waiting for the proper cartridge version at the moment as I want to add it to my own diag-cart board.
The tool I use is GB6 for testing, its not designed to be a diagnostic tool, but it tests a lot of the system and its the only program I really use.. Beyond that its guesswork and scope readings. As you know now with your new LA, you can quickly find things which would take me months to find otherwise. A lot of it is noise related glitches on the ST bus which are a nightmare to track down. Pretty much have to guess at what line is doing it and keep trying
There are not many who will really understand such problems, I mean look at the nightmare the DMA issues cause on the STe. Its why I made the choice to jump to designing a new ST board and debugging that instead. The ST faults are never ending and seem to be getting worse over time, I am really "done" with messing about with those faults. Once its been tested out and working stable, then it will start getting upgrades. Of course we need good tools to get the new STF board up and running.