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DOS/65 and Dual IDE-CF

Great news. I now have my V1 65C02 CPU working with my V2a Dual IDE-CF board. It required creation of the SIM (same function in general as the CP/M BIOS) and MONITOR code to initialize and then drive the board and CF card under DOS/65. Creating the 65C02 code was not that difficult but the smaller available code space in the MONITOR EPROM forced by mapping the S-100 I/O space into a memory page starting at $F800 was a challenge. Besides cleaning up the MONTOR code to save space I also had to greatly simplify floppy and IDE-CF error reporting and recovery. In the long run I will reallocate some code from the MONITOR to the SIM to free up EPROM space and add error reporting details back in.

The initial release has only two 8 MB CF drives. I will add two more and should be able to do that with no MONITOR changes.

The CF card and drives are the same ones used for CP/M with C: dedicated to CP/M and D: dedicated to DOS/65.

Some notes on the attached MONITOR, SIM, and BOOT code.
a. MONITOR uses 65C02 operands and will not work with an NMOS 6502 CPU.
b. System boots from a 1.2MB, 5.25 inch floppy with one system track but that can be altered as needed.
c. MONITOR code (MON1000.ASM) assembles with the WDC 65C02 assembler.
d. BOOT (BOOT12.ASM) and SIM (SIM400X.ASM) assemble with the DOS/65 ASM.COM assembler. Both can be easily changed to use TASM or the WDC assembler.
e. SYSGEN.COM will write physical, sequential sectors to the system area of a floppy or IDE-CF drive but I have not tested it with an IDE-CF drive.

If you have questions please ask away.

Rich Leary

Attachment: BOOT12.ASM
Description: Binary data

Attachment: SIM400X.ASM
Description: Binary data

Attachment: MON1000.ASM
Description: Binary data