TRS-80 Model I

[Tony Duell]

> 
> On 2/4/07, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
> > If you don't want 'the first', try to get a Model 4, original
> > (non-gate-array) CPU board versions. It's got a couple of features not
> > found on the earlier machines, including an 80*24 text mode display and
> > selectable memory mapping allowing RAM at location 0 so you can run
> > normal CP/M as well as TRS-DOS, LDOS, etc.
> 
> Ooh... didn't know that the M4 could run CP/M.  When I was in High

There was a CP/M+ for it (the M4 could officially take 128K of RAM, I 
believe there were hacks to put 256K chips, not 64K in bank 1...).

Mind you, I am not sure why you'd _want_ to run CP/M on it. The 'native' 
TRS-DOS 6.x (aka LS-ODS) is a much nicer OS, with loadable device 
drivers, some (limited) I/O redirection, a better scripting facility, etc.

> School, our "Computer Math" class was done with a M3 and M4 running
> TRS-DOS.  If I'd known I could have gotten CP/M for it at the time (c.

The Model 4 will run all Model 3 software, including booting all Model 3 
OSes. If you were running Model 3 TRS-DOS (TRS-DOS 1.x) I can understand 
why you'd want to run something else :-)

-tony