[Coco] 2764 EPROM vs 2864 EEPROM

[Steven Hirsch]

On Sun, 29 Sep 2013, Gene Heskett wrote:

> Now that worked, but the file links are all #403.  I will order the big 
> Willem kit if and when a good CC arrives

If you are thinking of buying from Sivava, be aware that you will have 
none, nada, zero, zilch tech support.  He is happy to take your money, but 
does not respond to e-mail after the unit is in your hands.

Also, if mine is any example, it has been subtely modified from the public 
Willem standard and is dependent on Sivava's modified software (for which 
no source is available).

Finally, the charge-pump scheme used to develop the 21V rail for 
programming older NMOS parts is generally not able to source enough 
current for reliable programming.  There's plenty of discussion on this on 
the Willem forums (not sure they are still online).  I ended up buying a 
retro-fit kit from one of the folks there since I blow a fair number 2708, 
2716, 2732 etc.

As always, Caveat Emptor!

Steve



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