Uh oh guys, I’m back again unfortunately. It seams that I have somehow broken my JDM Module 
Some of the “Old Timers” around here might remember I had some trouble initially getting my JDM to work properly. The problem would seam to be originating from the R2, Q2, R3, DB8, DB4, and RB7 portion of the programmer but I am getting ahead of myself. Let me start from the beginning.
1. What Happened
What happened was one day I was practicing with my PIC, playing around flashing LED’s and practicing with buttons and whatnot, I was probably on burn number 5 or 6 for the evening when it broke. I was performing a write operation when I received a prompt saying that “verify failed at code address 1F00h” and the write was aborted. When I attempted to restart the writing action I received my all familiar “Verify failed at code address 0000h”. Needless to say I was disappointed. I then attempted to read the contents of the chip to determine if it was the chip that was damaged or the programmer. I was confused when the programmer READ the chip!?! ??? I then compared the data that was read from the chip to the original file that I was trying to burn and they were identical up to code address 1F00h where the programmer failed. The code entered in the addresses 1F00h-1FFFh was all zeros. However, the EEPROM addresses did not read correctly and neither did the Configuration. EEPROM came back as all zeros and configuration came back with default parameters.
2. What’s Happening Now
I have since tried two other PIC’s in the programmer with similar results. The two other chips I tried are brand new chips that have never been used and the results of a read are as follows:
A. The Program Code addresses return the correct results, i.e. all addresses read 3FFFh, but the EEPROM still reads all zeros and the configuration is not correct either.
B. Any attempt to program the chip fails at code address 0000h as does blank check.
When I try to erase the original chip, IC-Prog returns saying that the chip has been erased but a read to the chip returns showing that the code is still there.
All of my voltages on the board have remained the same with respect to what they were before the problem. Here are my voltages just for a reference:
MCLR - 14.05V
VSS - 5.05V
RB7 - 4.56V
RB6 - 4.25V
And as I said, these are the same voltages that I measured before I started having the problem.
3. My Problem In Summary
To sum up my problem in just a few words I would have to say this: My programmer quit working in the middle of a write operation. The programmer still correctly reads the Program Code section of the chip but it cannot correctly read the EEPROM or the configuration. No write operations can be performed and the device cannot be erased. All voltages are correct, or are at least consistent with, Pre-Problem measurements.
I don’t know what do guys, to me my first suspect was that I somehow fried the transistor but since data is still able to be read from the chip I don’t know if i can still suspect the transistor or not. I have checked continuity between DB4 and DB8 and the emitter and collector of Q2 and I was able to determine continuity between the DB9 and the collector but no continuity between these and the emitter, as would be expected.
Any advice you guys could offer would be greatly appreciated as this one stumps me.
Thanks,
Shawn
P.S. I apologize about the length of this post, I tried to keep it as brief as possible but still try to describe the problem as best I can.
