Am 2. Juli 2013 08:46:15 schrieb "MikeS" <firstname.lastname@example.org>: > It turns out that there is a routine in the graphic ROM that checks for > presence of the VIDEO ON signal on PB5 of the VIA that is not in the > business version; the problem was a broken trace from the PIA to the VIA. Ah, a remnant of the old PET 2001 "don't access the screen memory while displaying" code - that waited for retrace before printing to avoid snow on the screen. This code is also the cause for the speed up poke that turned into a killer poke. Didn't think it was still in the Basic4 editor. André Message was sent through the cbm-hackers mailing listReceived on 2013-07-02 07:00:03
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