This was sent to the plus4 list. Previously I knew (from Andreas Boose) that the $8B opcode (or was it $AB, anyway the opcode with non-deterministic behaviour) behaves differently if DMA takes place between the opcode fetch and the parameter fetch. Marko ---------- Forwarded message ---------- Date: Thu, 23 Jul 1998 13:55:15 +0200 From: Tibor Biczo <firstname.lastname@example.org> Reply-To: email@example.com To: firstname.lastname@example.org Subject: ANE Hi there, I was playing a bit with ANE opcode $8B, and found out, that the result is also dependant on the instruction which was executed before it! I had the instruction execute on a fixed raster dot, and the result was mostly stable (Certain bits sometimes seemed to be not stable), and if I changed the instruction before it so that the registers remained the same (like changing an STA to an STX) the result of the instruction changed. I haven't gone into details, much further. This was on a 8501, and I wonder if one of the C64 owner would check this on the 6502? Tibor Biczo / Crown of GOTU --this message went through the email@example.com emailing list--- - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail firstname.lastname@example.org.
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