T O P I C R E V I E W |
DarrenAnderson |
Posted - 08/28/2009 : 16:34:48 Hello, I have a Willem programmer I believe it is a PCB 3.1 Version Dual Power.
I also believe that DL had at one time sent me a power supply conversion diagram to help with my Low Vcc and Low Vpp while programming Eproms. All was working Perfectly untill this time. I can not get a good "read" on a 27C256. I have came to this conclusion by lining up the Images from the chip and doing a compair. And also while trying to Verify the read. Failes at various places. I have tried 3 Computers, 4 Cables ect...
I did find a broken resistor labled 2K2 in the upper left side, but with that broke I could not even detect the hardware. Any thoughts on where to start looking? I have verified proper Vcc 5.2 Volts but that is about as far as I have gone.
I have read that there is a resistor mod that cam be made to make it read better, or did I mis-read that. Please help, I really need to read this Chip. Thank you |
3 L A T E S T R E P L I E S (Newest First) |
DarrenAnderson |
Posted - 08/31/2009 : 21:25:15 OK, SO I went through this Programmer again, and this time I paid extra attention to the DIP switches. SW 5 and 9 both read OPEN when closed. Ran Jumper wires and VOLA she worked just fine. |
DarrenAnderson |
Posted - 08/30/2009 : 09:01:11 OK, new problem. I thought I would test another type of Chip. I used an AT29C512 Flash Chip. No Joy on that one. reads, but not correct, and Can't erase at all, times out. Tried 3 Cables and 2 PC's Anyone ever See this type of PCB3? andone have the "parts Placement" diagram? Or Schematic? The PCB 3 Schematic posted here, does not have all of the right parts, or proper Values.
And it was DL that had sent me the "new" power supply diagram. I found it in an old E-Mail. |
DarrenAnderson |
Posted - 08/28/2009 : 19:00:26 Here is a Shot of My Programmer The upper Left Resistor was the broken one. But I found an exact replacement.
Image Insert:
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