One of my ongoing projects is building a replica Acorn System 1 computer and this has required programming EPROMS. Programming EPROMS in itself is fast, but erasing them ready for re-use is time consuming.
So for this project I decided to use EEPROMS. Ebay had numerous Chinese sellers listing all types of devices from 2K to 64K and I bought a selection of AT28C16 (2K x 8) and AT28C64 (8K x 8)
I opted to use an 8K version initially as that fitted my IC socket on my development machine.
I’ve documented the problems I’ve been having with getting that machine to run, and as one options to try and sort out my problems, I decided to abandon the EEPEOMs in case they were causing some weird incompatibility issues. To be fair I’ve not really got much experience with EEPROMs so it was possible there was some “got-ya” I wasn’t aware of, so back to trusty (but slow development cycle) EPROMs seemed sensible for now.
This however meant using my crappy slow EPROM programmer. It’s a serial programmer, running at 1200 baud and the software is so old that it would only run (just) on an old Windows XP laptop. It was a real pain.
When my brother passed I kept his Stag EPROM programmer. This is a nice machine but again the software is really old and won’t run on a modern PC. I did think about writing new software but who has the time.
I decided to bite the bullet and buy a new programmer that could program anything from a 2716 up.
It really isn’t as easy finding a device as it sounds.
Forget all the Chinese ones. All their claims about being able to program anything are a little over hyped when you actually check the supported device list. None will program the 2716 or any device that needs over 18v for the Vpp.
I couldn’t find any second had programmers and every google search kept sending me to Dataman who seem to be the only game in town these days. As a kid I’d always wanted a Dataman programmer; specifically an S4 machine, but they were wayyyy to expensive for me.
A few days ago a brand new Dataman Pro-40 landed on my door step. We won’t discuss how much it cost, but I’m on bread and water for the next month.
That said, you get what you pay for.
I did have some weird problems installing the USB drivers on both of my Windows 10 machines but a couple of days later the problem just cleared itself and everything has been fine since. I’m wondering if there were background Windows updates being downloaded.
The Windows software is nice and easy to use and it’s these things that make it a pleasure to use.
The software’s all in English for one thing. Quite often if you do something; program or verify device it will ask if you want to do it again making it a lot faster to process many devices quickly one after the other. In fact, they have added a “YES” button to the actual programmer. Old chip out, new chip in, set the locking leaver and press the button on the device and the software just runs again. It makes it really quick especially when checking ICs.
This leads me onto the fake Chinese EEPROMS I’d bought.
My new Dataman Pro-40 will also test jelly bean type logic ICs and memories.
I’d used it to test my stack of 6116 memories and was pleasantly surprised to find only one out of 20 was faulty. I’ve had them in my junk box for years so I was actually amazed at this result.
I tested the ten AT28C64’s I’d bought and one of them was found to be faulty. Interestingly it was the one device that I’d been using in my development system. The other nine IC’s were fine.
I then tested the ten AT28C16’s I’d bought. Nine of them were faulty. By the time I’d finished I could spot which were the fakes and I left the one I thought might be real to the end and that’s the only one that passed.
Again, you get what you pay for I suppose… though I didn’t pay good money for a box of fake/faulty chips. I wouldn’t have mined so much if a couple had been faulty, but nine out of ten… I think that’s taking the micky.