On 1/03/2017 8:02 AM, smf wrote: > > > On 28/02/2017 15:06, geneb wrote: >> >> Patches that were done were applied to the BIOS, not the ROM. Keep in >> mind that under CP/M, the BIOS is loaded off of disk and isn't >> ROM-resident. CP/M is kind of a stack. The BDOS, the BIOS, and the >> CCP. The BDOS is the same for every CP/M system. The BIOS is modified >> to match the hardware that CP/M is running on, and the CCP is >> basically equivalent to COMMAND.COM in DOS - it's transient. > > The phone call was about the boot ROM for the Z80, that worked out > whether to go into C64 mode or C128 mode. Before that call the 6502 > started first & it tried to handle the mode switch, but that caused a > problem with the magic voice cartridge. > > It had nothing to do with CPM. > It makes sense to use the Z80 to handle the mode switch since after reset it starts running whatever code is at address 0000h. Message was sent through the cbm-hackers mailing listReceived on 2017-03-01 01:00:55
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