Yes, having A FP should be seamless, least it was on my old Altair
when it behaved.? There is no reason why CP/M should not run
with a FP.? Also the blinkin lights thing.
The Xmodem bug,? That may be a feature. ;)? Modem program in
the CP/M space were always troublesome as some wanted a well
configured IO byte, others did direct IO and had to be tweaked for
the IO device in use (SIO-A or B, 8251, 6850, 2651, 16450,
SIO/(drt or SIO2)? and many others often different enough.
DDT the likely clash is RST7 (address 38) as DDT uses that as a
debug return point.? ?Usually front panels had port FFh as an input
from the FP switches (sense, often used by non cpm for setting up
what IO exists).? Also FFH is the opcode for RST7 so missing memory
(altar/imsai) has pull-ups so by default no ram, is a RST7.
FYI the most nasty bug on the Altair was noise on all the front panel
wires to the bus causing the appearance of "flying bits" and crashes.?
DDT loads to 100H then senses the base of BDOS and relocated
to under that so the space from 100h to below DDT is available for?
user programs that would nominally be at loaded at 100H when
finished or debugged.
