Over the time I have been putting JiffyDOS on FLASH ROMs with adapters to fit in 2364/231228 sockets, I have found a handful of users who experience issues with the FLASH ROM option on C128 machines. I replace them with normal EPROM-based versions, and the problem disappears. It only happens on flat C128s, and rarely. I am using Atmel AT49F001 with 55ns or 70ns speeds, which should be considerably faster than the original ROMs, and are faster than the EPROMs I use to replace the problem ones. It's not an issue, per se, as I can address it by swapping out FLASH for EPROM, but I thought the group might be interested in the fact that it occurs. Since the adapter is simplistic and passive, and I did use a ground plane and proper high frequency routing rules when creating the PCB, I doubt it is the PCB. THe pins and traces as gold, so contact should not be an issue. Thus, I think it is the FLASH, but not sure if it's speed, drive capacity, or something else. As I've had other things of higher priority, and swapping them with EPROM always fixes the issue, I have not pursued any research on the issue. Since I don't have one of the affected units, I can't provide much more detail, though if there is interest in understanding this further, I could see about getting a customer to swap out their unit for one in my stock so I can probe it. Jim -- Jim Brain email@example.com www.jbrain.com Message was sent through the cbm-hackers mailing listReceived on 2012-12-04 19:00:12
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