Programming 2708's - test-drb@ccmp.vtda.org

26 Jun 2005

On Jun 26 2005,  0:49, lee davison wrote:
...

 >  What programmer can I look for that has the
ability to program a
> 2708? 
 I have a Softy 2 that can do it if you're really stuck.

  Not just that, the programming algorithm is
different to most
 other EPROMs. IIRC you have to program all locations in sequence,
 giving each one a 1ms (IIRC) programming pulse, and repeat that
 50 times. 
 Any bit in any byte can be individually programmed from 1 to 0.
 There are no sequence requirements, the programming pulse is one
 pulse of 50ms per location programmed. 
Not on any of mine.  Some later EPROM types can be programed either
way, but not original 2708s.

...
   You can't
program odd locations like you can in later EPROMs. 
 You can, it's EPROM microcontrollers like the 68705 that need to
 be programmed in sequence. 
Sure you're not looking at the specs for a 2716?  Tony's information is
correct for a 3-rail 2708 according to my Intel, Motorola, Texas data
books.

-- 
Pete						Peter Turnbull
						Network Manager
						University of York