Author Topic: CPM3SEMI.EMS ?  (Read 127 times)

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Online JohnElliott

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CPM3SEMI.EMS ?
« on: 11:53, 15 February 19 »
I'm not sure if this belongs best in Hardware or Applications...
According to 80TRK.DOC at http://gaby.de/ftp/pub/cpm/znode51/germany/amstrad/cpconly/cpmplus/patches/ , the Dktronics Silicon disk had a custom CP/M startup file, CPM3SEMI.EMS. Has anyone seen this in the wild?

Online Bryce

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Re: CPM3SEMI.EMS ?
« Reply #1 on: 12:20, 15 February 19 »
It's probably on the disk image here: http://www.cpcwiki.eu/index.php/DkTronics_CPM

I've also an original of this disc somewhere too, so it's probably "in the wild" there.

Bryce.

Online JohnElliott

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Re: CPM3SEMI.EMS ?
« Reply #2 on: 22:08, 15 February 19 »
Both the CP/M 3 drive images in that location have a C10CPM3.EMS that looks identical (except for a single byte) to the stock one. The one-byte change is to ignore the result from KL PROBE ROM when CP/M is launched:
Code: [Select]
        ld      c, 0FFh
        call    KL_PROBE_ROM
        ld      de, -513  ; Check that ROM is version 0201h
        add     hl, de
        ld      a, h
        or      l
        ret     z    ; The DK'Tronics versions have a plain RET here
;; Abort with "This program will not run in this environment"
;

If I read the manual aright, CPM3SEMI.EMS is created by PATCHER.COM, which is in turn created by the |SETCPMPLUS command. I see the ROM is linked here, so it looks like I need to extract PATCHER.COM and run that to get CPM3SEMI.EMS.

... Yes, that seems to work. PATCHER.COM is at offset 0x25F8 in SD212.ROM, so I was able to extract it and run it to generate CPM3SEMI.EMS.
« Last Edit: 22:13, 15 February 19 by JohnElliott »