>> Does that matter? The original test bit (in $d016) crashed the >> system because it disabled the dynamic RAM refresh (therefore, it >> was removed). > > You mean: There are chip revisions where the test bit actually does > something? On my 6569 (datecode from early 1983), it was a no-op. (reg $16 bit 5, "RESET"). Presumably it actually has function on the 6566. On the 6569R1 it is a register bit, but the metal track running from its output just stops in the middle of nowhere. It is going in the direction of the X/Y counters; supposedly it reset those counters. No 6566 die pictures to check, unfortunately :-( On the 8565 the register bit is still there, but the metal track has been ripped out. Segher Message was sent through the cbm-hackers mailing listReceived on 2013-05-23 21:01:00
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