[Coco] Coco 2 question

[Phill Harvey-Smith]

Quoting "Bruce W. Calkins" <brucecalkins at bellsouth.net>:

> I've had/have a CoCo 2 with 64k Color Basic.  It worked fine.  I played
> around with the all ram mode and loading Extended Basic from tape.  As I
> recall It did not take much to crash that system and lose all data in RAM.

This is where I think Dragon Data got it right with the Dragon 64, it had 2
copies of the basic rom (equiv to ECB on the CoCo), one assembled at the
default $8000 address, and one at $C000. When the machine is turned on 
it boots
from the copy at $8000, which is pretty much compatible with the 32, however
the default EXEC address is et to point at a routine that will switch to the
second copy of basic and copy it to RAM at $C000, giving you 48K for basic. It
also sets some flags in low ram so that when reset is pressed, it will check
which mode it should be in, and boot it apropreately, keeping the basic
program....asuming that nothing has got fatally corrupted.

Phill.

-- 
Phill Harvey-Smith, Programmer, Hardware hacker, and general eccentric !

"You can twist perceptions, but reality won't budge" -- Rush.

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