problems with JDM programmer

I have built a jdm programmer but it does not programs the pic 16f628 or EEprom 24C08.(which it was supposed to do)
When I programs the device, it gives a message : Verify failed at address 0000h
But when I read the device or programs it with 0000 at all memory locations, it does that without any problem and verifies as well.

What could be the probable reason. Please tell me.

you could explain it all in one thread... i check your other thread

Anurag_Singh said:

I have built a jdm programmer but it does not programs the pic 16f628 or EEprom 24C08.(which it was supposed to do)
When I programs the device, it gives a message : Verify failed at address 0000h
But when I read the device or programs it with 0000 at all memory locations, it does that without any problem and verifies as well.

What could be the probable reason. Please tell me.

Click to expand...

Pehaps,You software has code protect ON. you try to remove that. also the driver software can be st for verify during programming. instead of verify after programming as this would not be possible once you check the code protect on

If your JDM is with self supply derived from the COM port pins, many problems are being faced. check the Vdd and Vpp voltages. Vdd should be noise free and Vpp should be 13V DC
try to rewire it to JDM B type with external power supply.

By the way what design is it?