Changes
/* CPM2.2 with Memory Expansions */
After initialisation, the next two patches are helper functions, which occupy free space between CP/M modules. One is at 03E9h, in the gap between the CD and TE modules; the other at 0EE2h, in the gap at the end of DD. The first one backs up 128 bytes of memory at 8080h (which is normally used by the font) so it becomes available as a transfer buffer. The second reverses this, restoring the font.
====Disk access====
The disk access functions follow; these are placed between 8960h and 89FFh, in memory that's probably reserved for the system message table. Since they page memory, they switch to a local stack, which grows down from 3CFEh.
RET ;success
) and FLUSH INIT (a simple RET).
====Banked BIOS====
Dk'tronics Bank Switch software comes with NEWCPM.COM CP/M program which installs a 61K TPA CPM2.2 which uses the Dk'Tronics RAM. The documents describe how to make this CPM. They are repeated here and a pre-made dsk is linked to this page.
===ENTER FIRMWARE===
Dk'tronics NEWCPM.COM doesn't support using ENTER FIRMWARE from TPA because it runs from bank 2 of memory.
===Creating the DkTronics 61K TPA CPM 2.2===
