JDM PIC programmer troubleshooting

Hello, A while ago I came across a schematic for a slightly modified JDM PIC programmer which I just finished building. Unfortunately using it with IC Prog did not yield good results- even though Vdd and MCLR voltages are present, I am only getting blank data when trying to read/write a

16F84A chip.

  • What other signals should I be checking and what are the expected values ?

  • What are reliable settings in IC Prog ?

  • Does the schematic look correct? I compared it with the original design and noticed a 2.2k instead of 1.5k resistor and the transistors are different, though they seem to have similar specs :
    formatting link

Thank you!

Reply to
grubertm
Loading thread data ...

What are the value of those voltages?

Another item on a 16f84a. IIRC its Vpp has to have a voltage of 13V nominal.

Start with Vpp and Vdd values. If Vpp isn't at least 12V it isn't going to program.

Probably not critical. The biggest problem with the JDM programmer is that it requires a real serial port (i.e. +/- 12V signals) to work properly. Most modern serial ports swing at much lower voltages.

BAJ

Reply to
none

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.