On Tue, 25 Sep 2001, Ruud Baltissen wrote: > It is a shame to have so much power at hand and then not being able to use > it. This brings me to an old idea: replace the C128 EPROMs with C64 ones > that have been altered slightly because of the MMU at $FF00. This would mean > that one has complete control of the MMU, including the banks, even in > C64-mode. That idea wouldn't work very well, since the LORAM, HIRAM and CHAREN bits work in a totally different (and in my opinion, more logical way) in the C128 mode. One of the LORAM and HIRAM bits selects the color memory bank (two banks of $d800-$dbff) for the CPU and the other selects it for the VIC-IIe, and the CHAREN bit selects whether the character ROM is enabled in the VIC-IIe memory space. In the C64 mode, there is only one bank of color memory, and the character ROM is constantly enabled in two of the VIC-IIe banks ($0000-$3fff and $8000-$bfff). Marko Message was sent through the cbm-hackers mailing list
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