[vcf-midatlantic] RAM Test/Diagnostic ROM for Rockwell AIM-65

[Jonathan Chapman]

All,

Finally got some time to clean up the source for our RAM test/diagnostic ROM for the AIM-65:

https://github.com/glitchwrks/aim65_memtest/

Initial work was largely done by TangentDelta. This was written to help diagnose and repair some dead AIM-65s. The test will run on a minimally functional AIM-65 -- all you need is a working CPU, ROM socket, and display board. It performs the following tests:

* ROM checksum
* Stack page quick write presence
* Zero page quick write presence
* RIOT single-pass memory test
* Full system memory test

The ROM checksum and stack page tests are accomplished with macros so that they can run with no RAM, since of course that might be faulty! Once the stack page passes, zero page is tested. With stack and ZP tested, the RIOT and exhaustive system memory tests are performed. These tests are more complete, since we have a minimally functional system by this point. The exhaustive test is based heavily on the routines from the OSI MEMORY TEST from OS-65D 2.0, published in OSI Small Systems Journal, Volume 1, Number 3, September 1977.

Thanks,
Jonathan