The 6502 architecture can suffer in one area in particular with faster parts on read cycles and that is at the end of the cycle; Fast parts sometimes are faster to release data and let it go invalid. The '02 family can require 5-10 ns of hold time which might as well be forever if you don't have it. -----Original Message----- From: email@example.com [mailto:firstname.lastname@example.org] On Behalf Of Jim Brain Sent: Tuesday, December 04, 2012 9:18 PM To: email@example.com Subject: Re: FLASH ROM incompatibilities with C128 On 12/4/2012 8:12 PM, Julian Perry wrote: > Hello Jim, > > Wednesday, December 5, 2012, 1:06:45 PM, you wrote: > >> On 12/4/2012 5:19 PM, firstname.lastname@example.org wrote: >>> On 2012-12-04, at 19:34, Jim Brain wrote: >>> >>>> 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. >>> It might be useful to know what it is about (you say 128 only and only flat and only some of them? Or all of them but not always? >> Only flat 128s >> Only a few (3-6 of them in the 3 years I have offered JD) Never any >> other unit types. > I had the incompatibility problem you mention (from a JiffyDOS rom, > which you kindly and promptly replaced with an EPROM :) ) - and my > machine was a plastic-cased Commodore 128D (not DCR) Ah, I stand corrected. The plastic C128D uses a flat 128 mobo, as I recall. Jim Message was sent through the cbm-hackers mailing list Message was sent through the cbm-hackers mailing listReceived on 2012-12-05 03:00:49
Archive generated by hypermail 2.2.0.