Hallo Jim, > ... and only reads are required to select the bank. My first idea was that that should be doable. IMHO one condition is that it should be compatible to the original C64. There are enough unused places in the ROM that could serve for this purpose. The nicest one is at $FFF6 but had only four bytes, meaning only four banks. But then I thought of this: I test some changes to the System ROM by trying it out in RAM first. The first thing I do is copying the _whole_ ROM. Thus reading the bank switching mechanism as well. OK, I as person could avoid that. But what about programs out of the box that use the same trick? Just came to my mind: what about JiffyDOS and other altered ROMs? There is no guarantee at all that the unused places are still free. There is a possible solution, it looks like the one a FlashRAM uses. I recently learned, thanks to this list, that first some 'magical' addresses have to be written to. What about first reading some particular addresses before reading the address that sets the bank? Disadvantages: - the reading of the addresses will cost more time - you'll need more hardware than a few simple address decoders. -- ___ / __|__ / / |_/ Groetjes, Ruud \ \__|_\ \___| URL: Ruud.C64.org De informatie in dit e-mailbericht is vertrouwelijk en uitsluitend bestemd voor de geadresseerde. Wanneer u dit bericht per abuis ontvangt, verzoeken wij u contact op te nemen met de afzender per kerende e-mail. Verder verzoeken wij u in dat geval dit e-mailbericht te vernietigen en de inhoud ervan aan niemand openbaar te maken. Wij aanvaarden geen aansprakelijkheid voor onjuiste, onvolledige dan wel ontijdige overbrenging van de inhoud van een verzonden e-mailbericht, noch voor daarbij overgebrachte virussen. APG Algemene Pensioen Groep NV is gevestigd te Heerlen en is ingeschreven in het handelsregister van de Kamer van Koophandel Limburg onder nummer 14099617 The information contained in this e-mail is confidential and may be privileged. It may be read, copied and used only by the intended recipient. If you have received it in error, please contact the sender immediately by return e-mail; please delete in this case the e-mail and do not disclose its contents to any person. We don't accept liability for any errors, omissions, delays of receipt or viruses in the contents of this message which arise as a result of e-mail transmission. APG Algemene Pensioen Groep NV is registered in the trade register of the Chamber of Commerce Limburg, The Netherlands, registration number: 14099617 Message was sent through the cbm-hackers mailing listReceived on 2013-05-27 07:01:33
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