junebug vpp problem

[alwindawee]

Hi, I assembled the junebug programmer on a bread board but without the tutor, it's works well but when I calibrate VDD, here I get an error message tells

"Could not fully calibrate unit. The USB voltage may be too low to completely calibrate."

I checked the wiring and there is no problem, I'm think there is a problem with the MOSFETs, any suggestions.

thanks in advance.

 

[3v0]

I do not recall ever seeing that message.

If the voltage is right and the PIC thinks it is wrong there could be a problem with the voltage divider on the pin sensing the voltage.

Or something else is messed up due to using the 18F4550 instead of the 18F2550.

Which schematic did you build from.

 

[mvs sarma]

the issue is Vdd adjust. This doesn't exist in JUNEBUG. Thus no need to use that step even thought pickt2 software has it.
you can go ahead to troubleshoot and check and set the Vpp

 

[alwindawee]

thank you for your replies, first I found one 18F2550 in my junk box and I used it, and about the voltage divider I checked it too and every think is OK, and if it was as mvs sarma said then there is no problem.

thank you again.