Marko Mäkelä wrote: > What was the code you added? Just a simple $100-$1ff memory test and > then a jump to ($8000), where the cartridge would also be mapped? I > guess the cartridge will then complain about the KERNAL and BASIC ROMs > and any RAM above $1000, as they are not available in the UltiMax > configuration. There are 1014 $aa bytes at the end of the 8k ROM, > which is pretty much space for additions. I'm pretty sure Nick simply switches back to the normal EXROM configuration right after an initial startup sequence. I have a copy of his modified ROMs, but didn't want to modify a Supergames cartridge. I think I'll add some logic to a standard third-party 8k cartridge to achieve the same functionality. Recently I had some problems diagnosing RAM failures in two machines (one SX and one C64A breadbox), because my normal diagnostic ROM did not come up at all. I wonder if the KERNAL crashed because it relied on some RAM portions to be okay, and if Nick's startup code would help in this case. I found another solution then: I have a Lemans game cartridge that runs in Ultimax mode, and it sometimes started up with a garbled screen. I was able to get an idea which RAM chips are damaged by looking at the pattern on the screen :-) Of course this would've been easier if the contents of the screen RAM are set to all $00 or $FF, and this is what I'll do next time, I guess. Nicolas Message was sent through the cbm-hackers mailing list
Archive generated by hypermail 2.1.1.