Howdy,

I have similar interests and I am presently trying the following
approach.
Tato has an interesting Windows based programmer software at:
http://ourworld.compuserve.com/homepages/tato/
This software programs most of the C62X family.  He also provides a
schematic  for his programmer.
The Tato programmer is very close to several others that interface via
the printer port.  I have ordered from
Electronic Bulk Buys:  http://cec.wustl.edu/~blw2/index.html
The Don McKenzie programmer board.  I think this board will work with
Tato's software with some minor hardware mods.  Several other programs
support the Don McKenzie board.  However I have not found another
programmer driver with an excellent Windows interface like Tato's.  I
hope to get this working as soon as the UPS guy delivers the Don McKenzie
board.
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