On 8/10/2011 2:27 AM, Anders Carlsson wrote: > Jim Brain wrote: > >> I'm now less concerned about demand for such an adapter, > > Very nice! > > As well as replacing broken chips, an adapter with programmable ROM > part would be useful for anyone who has a working drive with an early > DOS version. I had 2-3 drives of the 3040/4040 variety which were > equipped with DOS 1, how odd it might sound. I found in order to > upgrade, one needed to replace both the ROM chips and the RRIOT. We > discussed this at the Vintage Computer Forum and came to the > conclusion some adapter boards were needed, where I could plug in the > old 6530 and a small EPROM just like it is done on the 8250LP. > > Also it appeared 2532 EPROM's are not suitable replacements for the > 2332 (?) ROM's in the drive. They work fine in a PET computer though, > just not in the drive? We checked the pinout and saw some references > on pinball repair sites about them having the same problems replacing > ROM with EPROM, so perhaps this is a real problem and not just me > failing to program them properly. > > Most of this however are moot points now as I have traded away the > drives to other people. Of course they might want to make the DOS > upgrade later on, but then there needs to be a solution to the ROM > replacement. Would Jim's ROM-el work or is that only for 8K chips and > upwards? > > Best regards > I *think* the 2332 and 2364 pinout is similar, so a 2364 ROM-el could be used as a test. I'm happy to wire one up and send it somewhere, if someone can test it. My concern is that ROM-el looks like an EPROM electrically, so it could have the same issues. Jim -- Jim Brain brain@jbrain.com www.jbrain.com Message was sent through the cbm-hackers mailing listReceived on 2011-08-10 13:00:03
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