80-Bus News


April–June 1982, Volume 1, Issue 2

Page 20 of 55

MONITOR.COM and other scribblings by Jeremy Gugenheim

Well me dearios, at last I have put Nas-Pen to printer, and what goodies flow forth?? Read on, and if you have disks, CP/M, and MONITOR.COM (the best thing since sliced Nascoms) all your old Nas-Sys software can burst back into fruity life!! Firstly, one and a half mods to MONITOR.COM itself (Gasp!), this one can only be done if your MONITOR.COM came from Nas-Sys 1 (Tee hee!).

Do ‘DDT MONITOR.COM’, then ‘S2F5’ and replace

79 DF 60 EF 08 08 OD 00 with

EF 2E 00 79 DF 68 DF 6A

This gives you back your checksums in the Tabulate routine, separated from your bytes proper by a space and a full stop.

To change the cursor character, do your DDT etc etc, and change the byte at O877H, which should start out as 5FH. It is quite alright to replace it with a carriage control character, they won’t control the carriage, try 07H, or even B5H if you’ve got the graphics chip.

Something for all you dedicated Nas-Crunchers (compatible) is replacing the Y (copyright) command with the repeat keyboard routine from INMC-6 (compatible). You can’t type it in directly so you need to find some mug who is willing to work out the new addresses for you. If you are too lazy even for that, then, well, I’ve done it for you.

Do all your DDT and stuff, and ‘SA67’ this lot in...

OA67 21 C3 OA DF 72 21 80 OA OA6F 22 7B OC 21 80 02 22 2E OATT OC 21 50 00 22 30 OC C9 OATF OO DF 61 30 O7 2A 2E OC OA87 22 2€ OC C9 2A 20 OC 2B OA8BF 22 2C OC 7C BS CO 21 02 OAST OC O01 00 08 16 FF 7D FE OAOF 06 20 02 16 BF FE 09 20 OAAT 02 16 C7 7E A2 28 06 OE OAAF O01 7A 2F A6 T7 23 10 E4 OABT7 79 B7 C8 2A 30 OC 22 20 OABF OC DF 61 C9 76 70 00.

For those of you who just groaned because I’m too mean to type in the source, I’m not, it’s exactly the same as the INMC-6 (compatible) one with the addresses changed and a RET NOP replacing the original SCAL MRET. So, now the clever ones amongst you can work out how, by using the YO and Y1 commands, it is possible to turn the repeat on and off. You have 55 bytes to play with, that should be ample, or you could even make it execute automatically after a cold start, but note that after the workspace has been initialised.

Once you’ve MONITOR.COM installed, use the READ command to get ZEAP into your memory. DON’T let the GENERATE command have its evil way here, or you’ll really be in trouble, ‘cos MONITOR.COM uses the old screen to hold bits of CP/M that it requires for disk transfers. If you have Generated ZEAP then you’ll have to disable the Generate command. How do you do that? Simple, you can even use Nas-Sys for this one.

This is an OCR’d version of the scanned page and likely contains recognition errors.

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