Am Dienstag, 12. Juni 2018, 17:05:20 CEST schrieb Mia Magnusson: > Den Sun, 10 Jun 2018 15:50:50 -0500 skrev Segher Boessenkool > > <segher@kernel.crashing.org>: > > On Sun, Jun 10, 2018 at 10:17:17PM +0200, Gerrit Heitsch wrote: > > > On 06/10/2018 09:46 PM, Segher Boessenkool wrote: > > > >On Sun, Jun 10, 2018 at 06:42:02PM +0200, Gerrit Heitsch wrote: > > > >>On 06/10/2018 05:36 PM, Segher Boessenkool wrote: > > > >>>http://siliconpr0n.org/map/mos/6526/mz_mit20x/ > > > >>> > > > >>>The ports are the low half of the pins (PA on the left, PB on > > > >>>the right). > > > >>> > > > >>>(I have a .xcf if anyone is interested, marked quite a few > > > >>>signals, but I haven't done the port stuff very much. It's > > > >>>about 400MB). > > > >> > > > >>That looks quite different from the one I posted. Looks like MOS > > > >>did quite a bit of redesign between the NMOS 6526 and the HMOS > > > >>8521 (which still got labeled 6526). Might explain the little > > > >>differences in the way they behave. > > > > > > > >No, this is an actual 6526r4. This is an 8521r1: > > > > > > > >http://oms.wmhost.com/misc/MOS_6526A_CIA.jpg > > > > > > > >(and this is an 8520r4, the CIA used in amigas; it has a different > > > >TOD clock, and as you can see it's different from 8521 in other > > > >ways, too. But clearly 8520 and 8521 are more related. The > > > >lineage is almost certainly 6526 -> 8520 -> 8521: > > > > > > > >http://siliconpr0n.org/map/mos/8520/mz_mit20x/ ). > > > > > > Yes, but the 8521 is a drop in replacement for the 6526 (I have a > > > C64 Board with a 8521R0 on U2) and later revisions of that chip > > > have been labeled as '6526' again, probably to avoid confusing the > > > customers. You can tell them apart by the datecode or by the '206A' > > > or '216A' next to the datecode. > > > > _Almost_ drop-in replacement, yes. But the die photos are really easy > > to tell apart (an 8521 does not say "6526" on the die, it says > > "8521"). > > I can't remember which versions, but at least some version of the CIAs > can only be used as one of the two CIA's in a C64. Using it as the > other CIA causes keyboard problems. no, both can be (and are commonly) used in either position > And when using it as the CIA that > generally works causes interrupt failure in the common diagnostic cart > (the one that's not called dead test, not sure if it has a better name > than diagnostic). that is correct - some of those diagnostic tests fail with the "new" CIA -- http://hitmen.eu http://ar.pokefinder.org http://vice-emu.sourceforge.net http://magicdisk.untergrund.net ..nuclear war could alleviate some of the factors leading to today's ecological disturbances that are due to current high population concentrations and heavy industrial production. <US Office of Civil Defense>Received on 2018-06-12 18:03:40
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