Deep diving into buss error handling by reviewing the previous posts and the Lisa Boot ROM assembly.
http://bitsavers.org/pdf/apple/lisa/firmware/Lisa_Boot_ROM_Asm_Listing.TEXT
If I understand this correctly, memory $282 should hold the address that caused the bus error. In my case, I get
282 0002 0000
which I think is $020000 (high byte is ignored). Does that mean the problem is occurring at position 128kbytes in the RAM card? Not sure how to map that to a component/components yet.
#AppleLisaClone #RetroComputing
paulrickards /
npub1kz…gq050
2023-09-25 22:04:11
in reply to nevent1q…ltjy
Author Public Key
npub1kzs35cf9c5gj88xh5rc74rzwag262ac8mlweaat7ylxz9ar2afmsugq050Published at
2023-09-25 22:04:11Event JSON
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"content": "Deep diving into buss error handling by reviewing the previous posts and the Lisa Boot ROM assembly.\n\nhttp://bitsavers.org/pdf/apple/lisa/firmware/Lisa_Boot_ROM_Asm_Listing.TEXT\n\nIf I understand this correctly, memory $282 should hold the address that caused the bus error. In my case, I get\n\n282 0002 0000\n\nwhich I think is $020000 (high byte is ignored). Does that mean the problem is occurring at position 128kbytes in the RAM card? Not sure how to map that to a component/components yet.\n\n#AppleLisaClone #RetroComputing",
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