Re: IIc Problems!

[ab616@chebucto.ns.ca (Tony Cianfaglione)]

David Empson (dempson@actrix.gen.nz) wrote:

: 3. A memory fault in the IIc (could be anywhere).  Try the self-test
: (assuming this IIc has the UniDisk version of the ROM - the original ROM
: didn't do a real self-test).

   It looks like this may the culprit as he had a problem with 80 column 
characters appearing on the screen prior to this recent problem. 

: 4. A power supply problem.

   We tried 4 different power supplies (from working IIc's) with no 
discernable difference.

: Which ROM version does this IIc have?  You can check the ROM version by
: getting into BASIC (press Control-Reset if necessary after "Check Disk
: Drive" is displayed) and typing PRINT PEEK(64447).

   It's a 255.

: If it says 255, then you have the original IIc firmware, and there is
: one option open to you: you can connect an external 5.25" drive and try
: booting (ProDOS only) from that.  To boot the external drive, type PR#7
: from BASIC.

   Using the PR#7 external drive trick renders the same problem.  The 
external works fine on all of the other IIc's but has the access problems 
noted by the internal.  It must be ram related.  I guess this is a parts 
machine. :-(