Wellon VP-280 Eprom Programmer

[grobda]

Failed initialization, Self-Test indicated 'P21 High', Confirmed with logic probe.

All SMT stuff inside. Separated top PCB from bottom, bottom PCB line to P21 was not high so assumed something on top board was pulling the line high. Removed ZIF socked (its plugged into a turned pin socket which is soldered to the PCB) and followed P21 to any components connected to it. used two soldering irons as tweezers to remove smd components, and replaced with ones off a willem programmer I don't use any more. First two made no difference ('Y-2' 3-pole (transistor/diode?), 'SS-14' SMT diode) but third, another 'Y-2' at V13 resulted in programmer initializing correctly and passing self-test. Programmed a couple of flash chips and all seems OK.

I hate SMT stuff, but am glad I don't have to buy another programmer just yet.

 

[tb2000]

Nice repair! I thought i'd busted mine a while ago as when I went to burn an eprom I accidentally left in the power bridge from one pin to the next that you have to do when testing 2114 rams. It didn't want to burn some specific eproms but I think I was just unlucky with what i'd used as it appears to still read eproms and test out rams and ttl ok!

 

[grobda]

This was the component... with fuse for scale, its like nudging grains of sand, needle tip on iron looks like a javelin next to them.

I wondered about 2114's, I use a Galaxian PCB to test them. Which pins do you bridge?

 

[tb2000]

Yeah I hate surface mount stuff!

If I remember correctly, you need to bridge pin 18 (Vcc) of the 2114 to the pin right next to it (so it's getting it's supply voltage from two pins rather than one). I just use a component leg cutoff bent into a U shape. Then it should test out ok.

 

[DABYX]

Nice job! I have no idea how anyone can do surface mount repairs!
Whenever I've tried it's a chuffing nightmare.
Props!

 

[Ronnie Dent]

Nice repair! I thought i'd busted mine a while ago as when I went to burn an eprom I accidentally left in the power bridge from one pin to the next that you have to do when testing 2114 rams. It didn't want to burn some specific eproms but I think I was just unlucky with what i'd used as it appears to still read eproms and test out rams and ttl ok!

So if you bridge pins 17 and 18 you can test 2114 ram? which setting do you use on the programmer to test them?

Thanks Ronnie

 

[tb2000]

Nice repair! I thought i'd busted mine a while ago as when I went to burn an eprom I accidentally left in the power bridge from one pin to the next that you have to do when testing 2114 rams. It didn't want to burn some specific eproms but I think I was just unlucky with what i'd used as it appears to still read eproms and test out rams and ttl ok! 

So if you bridge pins 17 and 18 you can test 2114 ram? which setting do you use on the programmer to test them?

Thanks Ronnie

No, if you bridge those two you'll send voltage up a data pin! You need to bridge pin 18 and the next free pin next to 18 along in the zif socket with a little loop of wire. Then choose the 2114 ram test in the software. I believe later software removed the test, I'll look up what version I'm using for you if your version doesn't have it.

 

[Ronnie Dent]

Cheers, I can find HM2114 in the burn devices but not in test menu? but why would you burn to a ram?

Ronnie

 

[Ronnie Dent]

Nice repair! I thought i'd busted mine a while ago as when I went to burn an eprom I accidentally left in the power bridge from one pin to the next that you have to do when testing 2114 rams. It didn't want to burn some specific eproms but I think I was just unlucky with what i'd used as it appears to still read eproms and test out rams and ttl ok!

So if you bridge pins 17 and 18 you can test 2114 ram? which setting do you use on the programmer to test them?

Thanks Ronnie

No, if you bridge those two you'll send voltage up a data pin! You need to bridge pin 18 and the next free pin next to 18 along in the zif socket with a little loop of wire. Then choose the 2114 ram test in the software. I believe later software removed the test, I'll look up what version I'm using for you if your version doesn't have it.

Can you just confirm it's pin 18 and 19 to bridge? as that would be the next highest pin are am I being stupid?

Thanks Ronnie