New addition to the collection

allison ajp166 at verizon.net
Fri Mar 24 11:26:34 CDT 2017


I felt the poor 8085 CPU was under represented and my Tandy M100 was lonely
so I added a NEC PC-8201A. 

The 8201 needed some help to get it going.  Things like the foam around
the LCD to front bezel
was turning to powder and regardless of the battery used it was faulting
on low volts (blank screen)
plus the internal NiCd was dead and starting to leak.  Attacking the
power supply corrected the
/LPS (low power shutdown) fault due to a bad transistor and now it works
well.

Next step is to fill the two banks of ram as it only had the factory 16K
and can carry 96k.

The first software project is to get to near the bare metal.  That is a
way to load machine
language programs and run them where the first code will be a simple
Monitor.

At some later point I'd like to mod it so the load and store (cload
cstore in basic) insted of using
audio cassette tape will be to CF or SD mass storage.  I may have to
resource the rom to  to
do that or go from scratch.  I haven't decided on an OS or start from
scratch CP/M is a likely
candidate as porting it to 8085 is done deal and adding modern mass
storage of any sort
is easy (BIOS).  The CP/M route opens a door to a great deal of software
that will run on 8085
as not all that much required the Z80.   The only requirement is  64K of
ram from 0000H
and the as built memory management can do that. 


Allison



More information about the cctalk mailing list