CP/M-86 support#139
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90% of the code is by me, 90% of the comments and the docs updates are Claude and Gemini (because I hate writing docs and comments). This isn't finished by a long shot but a lot works already. Some attention needs to be paid to ensure there are no regressions to any of the DOS code, but I tried to be very careful about that. Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
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This isn't finished by a long shot but a lot works already. Some attention needs to be paid to ensure there are no regressions to any of the DOS code, but I tried to be very careful about that. @tsupplis I see my base page init is all fubar - I will fix that and maybe more will work. Edit - success! Confession - Claude helped me. I haaattte it.:) |
… System Guide ... and also analysis of the layout / live base-page dump from cpm86.exe emu ARC86 now both compresses and extracts successfully! Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
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FIXED ZORK!! It’s not accepting keyboard input yet that appears to be interrupt driven? I’m on it. |
Claude AI wrote some tests... and the comments. Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
and AI clanker docs again, sorry. Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
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IBM PC CP/M-86 ZORK now plays! |
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More discussion at tsupplis/cpm86-crossdev#10 |
Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
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Fixed Turbo Pascal IDE, STAT, LS, and more. Still fighting TED video. |
…yte Count. Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
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Pushed the branch again, now we report our CP/M version as 3.1. Added support for setting the CP/M version via EMU2_CPMVER (just like EMU2_DOSVER). Fixes Last Record Byte Counts for most CP/M-Plus programs. |
Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
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See tsupplis/cpm86-crossdev#10 and dmsc/emu2#139 for details. Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
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Pushed again, with support for ISX-style LRBC, add |
CP/M-86 programs in the 8080 memory model (and CP/M-80-heritage code generally) commonly terminate with a near RET to the warm-boot vector at offset 0 of the code segment, rather than a far RETF to the loader-supplied exit address. emu2 pushes a far exit address (PSP:0000 -> INT 20h) on the program entry stack. That satisfies a far RETF, but a near RET pops only the offset (0) and keeps CS, landing at code:0000 -- the base page -- which emu2 then executes as code. The program runs off into the base page / arbitrary memory instead of terminating (observed: dstat86.cmd spins printing its message / hangs). In the 8080 model the code entry point is 0x100, so code:0000 is never reached by normal execution; arm a warm-boot trap there that terminates the program. The trap segment is 0 (disabled) for the small/compact models, whose entry *is* code:0000. Verified: dstat86.cmd now terminates cleanly (prints its message once and exits), matching real CP/M-86 behavior; other CP/M-86 programs are unaffected. Shocking good analysis from Claude. Patch by me with Clauded comments. Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
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Pushed a small 8080 memory model fix |
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I'm unmarking this as draft because it's probably good enough now for a huge number of CP/M-86 programs! |
Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
Signed-off-by: Jeffrey H. Johnson <johnsonjh.dev@gmail.com>
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CP/M-86 support!
The goal is to match DOS-PLUS / CP/M 4.1 eventually.
When complete this will close #52.