Re: ZipGSX programming...

[David.Empson@bbs.actrix.gen.nz]

In article <jmk3.728283783@crux1.cit.cornell.edu> jmk3@crux3.cit.cornell.edu (Jay Krell) writes:
> This ZipGS's softswitches and such are retarded, IMHO.
> Anyone know why the took the route of stealing already used
> softswitches instead of the slot's switches?

Some theories:

- So that it wouldn't require you to set a slot to 'your card' (or
force you to put it in slot 3 or 4, which always have the DEVSEL I/O
locations available).

- So that it would work without a slot, as in the piggyback CPU slot
version (which never sold).

- So that it would be pretty much compatible with the standard ZIP
CHIP.  The same sequence is used to enable/disable the registers on
both versions, but the register contents are different.

> How about the TWGS? Does it use its slots memory and can you ID the
> TWGS by looking for ID bytes in Cx00?

The TransWarp has some fake memory in bank $C0, I think, which
includes an ID string and several routines you can call to set
operational parameters.  I've never looked into it in detail - I'm
sure a TransWarp owner can answer this question better.
-- 
David Empson

Internet: David.Empson@bbs.actrix.gen.nz    EMPSON_D@kosmos.wcc.govt.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand