SWTPC 6800 weirdness
vintagecomputer at bettercomputing.net
Wed Sep 7 10:17:56 CDT 2016
Ahhh.. okay, maybe I misunderstood. I was reading '4096 words of 8 bit RAM', I don't know 'words' that well so I put it in a calculator and it was telling me it was 8K. But docs suggested the original MP-M came with 2k. So setting the board # jumper to 4, if it was at 2K, would run $4000 to $47FF, and with 4K runs to 4FFF, which is what that board is doing.
Phew. So, it looks like I've got all the RAM working now. The only address space I don't have covered is from $5000-7FFF. Not sure if I'll need that.
So my next task is to run ROBIT. However I'm still confused about that. It says in the docs you want to set the highest and lowest significant bits of each of the lowest memory address and highest memory address to be tested. But it doesn't explain at all how to do that. It shows a listing for the program, but it looks like it's in assembly? Does anyone know how I'd get the system to test, say, from $4000 to $4FFF, as an example? Am I altering $A002 through $A005 using the monitor somehow? Or do I need some kind of assembly language?
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