Direct Keyboard Commands – Update &
More GEMPEN Mods.

by C. Bowden. (Tel. ____ – ______)

In Issue 1 of Volume 1 of Scorpio News, I described some BIOS modifications to provide immediate acting commands from the keyboard. I have updated and refined this software. In particular I have added a routine to allow the saving of Screen display to a Disk File (From the Operating System only), and altered the Screen Dump facility to allow it to be accessed from within any program. Previously it could only be accessed from ‘EDIT’ mode, which meant it would not work from within some programs that redefined the ‘EDIT’ key. Several more commands have been added, and the BIOS code has been altered to save memory, allowing more routines to be added.

My BIOS is a home-made modification of MAP80 CP/M 2.2 BIOS with some SYS18 routines patched in. It supports a wide combination of hardware e.g.; NAS­COM 2 or GM813 CPU, MAP4 or MAP32 paging, MAPRAM, GM833/​NE889 Ramdisk, 809 /GM829 FDC, 812/832 IVC/SVC, Nascom and/or Gemini Keyboards, Micropolis/​Teac Floppies; Rodime and Shugart Winnies. The only thing it does not currently support is the Nascom Screen or the GM849 FDC.

It should not be too difficult to patch the necessary code into any BIOS that is similar to SYS18 or MAP BIOS, I do not use CPM 3 much, since I think that the ZCPR3 system is far superior, but it would probably be possible to patch something similar into the MAP CPM3, for which the code is supplied. If you are using a recent GEMINI BIOS, then you have had it ! (Unless you care to disassemble it).

The code to be patched into the BIOS. can be supplied on a disk if anyone is interested. Contact me on the ’phone number given.

In the original article I described seven commands. The current version has 15 commands. They are accessed, as before, by entering ^T. This causes a prompt to be displayed on the top line of the screen, with the required operative key displayed in inverted video, as a reminder of the commands available. The second key may be a ‘straight’ key or Control key. The options available are limited mainly by the BIOS space available, and could be considerably extended if a longer BIOS is acceptable, or if some hardware options are not supported, such as RAMDISK or Winchester.