Many clone drives used a direct copy, an obfuscated copy, or a marginally modified 1541 drive ROM to power their units. Someone provided me a BlueChip/Amtech drive ROM, and I finally had a chance to look at it. It's a 16kB ROM, and the e000 looks almost exactly like the 1541 -05 or -06 ROM. The $c000 portion is radically different, or at least looks different at first glance. But, given the minimal changes in the upper half, I burned a copy and successfully booted a 1541 with it. Thus, I'm wondering if someone could help me decipher: * What is indeed different (of note) in the $e000 rom? * Why the $c000 rom is so different, and does it need to be that way (or, can I just replace it with a 1541 $c000 ROM image)? The files, if folks are interested, are at: http://www.jbrain.com/incoming/BlueChip/Amtech_BlueChip_ROM.BIN http://www.jbrain.com/incoming/BlueChip/Amtech_BlueChip_ROM_c000.BIN http://www.jbrain.com/incoming/BlueChip/Amtech_BlueChip_ROM_e000.BIN The latter two are just the first split in half. Jim -- Jim Brain brain_at_jbrain.com www.jbrain.comReceived on 2020-05-29 22:06:40
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