At 01:23 1998-03-12 -0500, you wrote:
>At 08:10 AM 3/12/98 GMT+2, you wrote:
>>Hi to all
>>
>>I'm looking at building a simple EPROM programmer for
>>the 2716 to 27512 EPROM's (All I need for now). I'll
>>probably use a PIC in there somewhere. So I was wondering
>>if anyone out there knows where I can get the programming
>>specs, or has them for me. I had a look around, I could
>>find the pinouts but that appears to be it.
>>
>>TIA
>>
>
>Programming these is quite straightforward. It basically just involves
>applying valid address and data, power supply (5 volts and programming
>voltage), and pulsing CE low for some predetermined amount of time, then
>reading back the value to make sure it worked. If it didn't work, repeat
>the process. If you have more than 25 reps, report an error and abort. For
>specifics, check out http://www.amd.com
>
>Good luck,
>Sean

There are a lot of algorithms to increase reliability.
A common method is to program and verify short times until it reads
correct, then overprogram a certain time.  That assures a margin.
Verification should best be done at both Vdd min and Vdd max.
/Morgan