Re: Microsoft Softcard problems

[mark@pokey.jsc.nasa.gov (Mark Manning)]

I have a CP/M card on my //e.  The reason I haven't transferred it to
the //gs is because the layout of the //gs is incompatible with what
the Microsoft card expects.

If you are unfamiliar with how the Softcard works, here is how:  Like other
cards for the Apple, the Softcard works on the off cycle of the Apple.  Or
in other words - the Apple computer produces a squared sine wave.  When the
wave is at one - the Apple computer does its work.  When the wave is at
zero, everything else does its work (including the Softcard).  Well, to make
a long story short - the Softcard expects the wave to be X long whereas
the //gs' wave is slightly shorter (or Y long).  The difference causes the
Softcard to go out of sync.  Now, this could all be a bunch of bunk.  I'm
not an electrician or a EEE person.  But I know about the sine wave, how it
works, and how it affects various things.  I also know that even in slow
mode the //gs is still faster than the //e.  Thus, it stands to reason that
the Softcard (which was made to ][+ standards) will not work properly on a
//gs.  It works ok on a //e (though every now and then it won't boot for
the same reason).

Your best bet is, if you want CP/M, to get a much newer card which was made
for the //e (or //gs).  If you are determined to use the Softcard, then I
would suggest turning off any kind of an accelerator you might have and
placing the system into its slowest mode.  This will help the Softcard with
trying to work with your system.

Keyboard problem:

The CP/M card has its own memory.  Certain of these memory locations were
mapped via ROM into specific places in the ][+'s memory so things like
reading the keyboard, writing to the disk drive, etc... could be accomplished
easily.  Unfortunately, these are not the same _exact_ memory locations
in the //gs anymore (which is why some DOS 3.3 programs do not work
properly under ProDOS).  Since the //gs does not read a keyboard in the
same manner as the //e did, it is to be expected that the Softcard would
have problems with this (and other things).  Again, your best bet is to
sell the Softcard and buy a CP/M card which is made for the //gs.

Of course, if you were REALLY industrious (sp?) you could rewrite the
CP/M operating system so it would allow for these changes.  No? ;)