On Thu, 27 Jul 2000, Nicolas Welte wrote: > First, you can detect a 128 by it's additional hardware and therefore can > sort out the 8502. The simplest thing to do is to check whether the data direction register at location 0 remembers the value you write to bit 6. The 6510/8500 has a 6-bit I/O port, while the 8502 has 7 bits (and the 7th bit is connected to the CAPS LOCK a.k.a. ASCII/DIN a.k.a. ASC/CC key). > You can also distinguish between 6510 and 8500 if the computer is > without any damage by testing for $de00 compatibility (running > programs in I/O or colorram space) Good idea. Running programs is not necessary; you can just read $de00 (or better, the high nybbles of the color memory - it's rather unlikely that anyone has any custom hardware in the color memory area) after synchronizing with the video chip (e.g. fill $3f00-$3fff with a known value, blank the screen, turn sprites and ECM mode off). > But I don't know how to distinguish between 6569 and 8565 from a program. Neither do I. Even the "ALWAYS SET THIS BIT TO ZERO" bit works the same on both chips (setting it has no effect). Marko - This message was sent through the cbm-hackers mailing list. To unsubscribe: echo unsubscribe | mail cbm-hackers-request@dot.tcm.hut.fi.
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