Hallo allemaal, I'm busy streamlining the disassembled code. During the proces I was reminded something: the BASIC code starts at $1C00. The range under $1C00 are variables and screen memory. That means we have a challenge: if we want to implement BASIC 7 in a C64 or other machine, some extra memory has to be found to store those extra variables. For the C64 it means $1C00 - $0800 = $1400 bytes have to be found. With a bit of 'luck' not all variables are needed. If possible, the rest could fit into the $Cxxx area. But what if not? Any other ideas are welcome In my expanded VIC-20 I can replace block 5 with 8 KB of RAM. That should solve the proble here. If possible, I want to use the rest of this RAM for BASIC variavles, leaving me with more space for the actual program. Do we have to worry about compatibilty? I can imagine there are programs around that use hard coded jumps or subroutines to access certain BASIC routines. I ran into such problems with the KCS Power cartridge with my 1541IDE project. The most simple solution would be to leave the original BASIC code untouched and implement the 7 code in the other pages of the FlashRAM. Again, ideas are welcome. About Mike's JiffyDOS idea: although the BASIC 7 ROM is 32 KB = 2 FlashRAM 'pages', not all is BASIC. With a bit of luck both can be implented. Just an idea. -- Kind regards / Met vriendelijke groet, Ruud Baltissen www.Baltissen.org Message was sent through the cbm-hackers mailing listReceived on 2013-06-07 15:00:04
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