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tomcw / mb-audit

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Use local copy of WAIT, not monitor ROM's #3

Closed tomcw closed 3 years ago

tomcw commented 3 years ago

On cea2, ("mb-audit: a Mockingboard test suite for emulators") Kent Dickey said:

I have a suggestion for 11:0E:00: you call the monitor routine WAIT to wait a number of cycles--and you care about the exact number of cycles elapsed (well, really you care about cycles mod 2, so if it's off by a multiple of 2 it's fine). WAIT on a IIgs is not cycle accurate, and it might not be on other monitor ROMs either since the WAIT description says it waits a minimum number of microseconds. So the IIgs ROM has extra code to ensure the CPU is running at slow speed, and this adds extra time. You would be better off creating your own WAIT in your code so that it's consistent regardless of the monitor code in ROM.

tomcw commented 3 years ago

6522 Tests B, C and D all assume WAIT is cycle-accurate (but not Test E - so I guess that was a typo).

tomcw commented 3 years ago

Fixed in 0.7-beta.