There's a 2K hole in the Model I memory map above the ROM
On Tue, 12 Apr 2022, Yeechang Lee via cctech wrote:
Is this the hole that causes stock Model I to not run CP/M?
The problem with CP/M on TRS80 is that CP/M expects RAM from location 0 on
Location 0 - FFh are used as a data structure for running programs, with
location 100h and up as the "transient Program Area", where programs load
TRS80 has ROM in bottom 16K.
There did exist MODIFIED CP/M ("FMG") that loaded above ROM, and ran
programs that weren't too "hard-wired" to expect specific load location.
Parasitic Engineering (Howard Fullmer) and Omikron Mapper both made
sandwich boards for the model 1 that moved things (under software control)
to run "real" CP/M. They both ALSO sold 8" drive conversions for the
Grumpy Ol' Fred ci...@xenosoft.com