Hi, Please see resolution below, if you are curious about how this turned out.
On Wed, Dec 20, 2017 at 09:18:50PM -0500, Mark G Thomas via cctalk wrote: > Hi, > > > On Wed, Dec 13, 2017 at 9:08 AM, Mark G Thomas via cctalk < > > [email protected]> wrote: > > > > > Hi, > > > > > > I am working on several projects requiring 2708 and 2716 EPROMs, and > > > am finding some of my chips will not erase, and some will not take > > > a program. I've also learned more in the past week than I wanted > > > to know about repairing Data-I/O 29a/b programmers. > > > > > > I vaguely remember in the 1990s baking such EPROMs in the oven, but > > > I do not remember temperature or time. I was surprised that Google > > > didn't turn up anything useful with this info. > > > > > > I'm sure someone here will have some notes on EPROM baking. > > > > > > Mark > > > > Mark, > > > > If this is an issue about reviving bad eproms? I assume you have tried the > > regular stuff. > > > > What process are you using now to erase 2708/16's? I have a simple eraser > > unit and it seems to always work. Some eproms go bad but I never have > > issues with erasing them. My point is that maybe you need a better prom > > eraser unit. > > They seem to erase fine, using a PRO-LOG 9103 eraser (box, timer, tube...) > > > I would avoid baking them until you have exhausted other > > options. Not sure what others think. This topic has come up before here, > > about putting them outside and all that. The erasers are all over ebay, > > and the hardware store is full of the correct types of lighting, why not > > make a box that will do the job? I assume there is more to it that > > simply erasing them. > > > > > > Bill After more experimentation I came to the following conclusions. 1) Some of my chips are legitimately bad, erasing fine but won't take a program. 2) Many of the chips were failing to program because my Batronix programmer apparently requires more current than my USB port provides. This surprised me because I have been programming chips for years using this programmer on this computer port successfully, and this is the first I have had the problem. Using a Anker powered USB hub solved things. My Batronix programmer even arrived with a cheap powered hub when I ordered it, but I never used it because it was shipped with an incompatible wall wart, but looking at it in the box gave me the idea that this might be the issue. 3) I thought I had ruled out the programmer (#2) because of troubles programming those same chips using another programmer, but I probably had the wrong chip type selected, or simply failed on some of the #1 chips so assumed that was my only problem. Mark -- Mark G. Thomas ([email protected]), KC3DRE
