Data I/O Series 22 EPROM Programmer help

From: Ian Primus <ian_primus_at_yahoo.com>
Date: Sun Oct 19 21:19:32 2003

On Sunday, October 19, 2003, at 07:21 PM, Pete Turnbull wrote:

> On Oct 19, 18:10, Ian Primus wrote:
>>
>> I have a very large pile of 27cx321
>> chips, made by a company called ICT, but I have been unable to
> program
>> them, since my programmer doesn't have the codes for them in the
>> manual, and they don't work at the normal 2732 setting.
>
> No, they don't, and if you try it, you may destroy them. They're
> high-speed (usually 35ns, but the suffix -35, -40, or -45 gives the
> actual number) 4k x 8 UV-erasable EPROMs, and to get the speed they use
> a different cell construction and a different programming technique.
> The bits in an erased device are "undefined" and whether you want a
> '1' or a '0' you have to program the actual value. Pinout is pretty
> much the same as a 2732 except that pin 20 is /CS1 instead of /OE, and
> pin 18 is CS2 (active high) instead of /CE.

Well, then I probably have two EPROM shaped paperweights...

>
> My ICT data book doesn't give the programming algorithm, which is
> obviously proprietary. It just says contact ICT or use a DATA I/O
> Model 29B with Unipak 2 or 2B firmware version V15.

Gah, figures. Does anyone need any ICT 27cx321 EPROM chips? I'll trade
for some regular 2732's...

> Oh, and like every other EPROM manufacturer I know, ICT say that
> exposing it to UV for longer than necessary will affect reliability,
> shorten the life, or in extreme cases, destroy the device, so don't
> expose them to a UV eraser (standard 12mW/sq.cm) for more than 20
> minutes. Overnight is a bad idea!

I have just been erasing chips with the standard setting on the Data
I/O's built in EPROM eraser, which is 35 minutes. But, I frequently
take them out earlier, since I figure "It's blank enough". I need to
get another eraser though, it's kind of a pain only being able to erase
two chips at once.

> --
> Pete Peter Turnbull
> Network Manager
> University of York


Ian Primus
ian_primus_at_yahoo.com
Received on Sun Oct 19 2003 - 21:19:32 BST