Quote Originally Posted by meho View Post
Bigpic 4 has usb ISP onboard and is not based on bootload process so the 8520 is programed externally and that works.
I tried another programming via RS232 -> COM1 with microcode but failed because of
bootloader problem.
no i did not reprogram 18F8520 because still don't know how to - was trying to load 18F8520_4.hex into MCloader but always the same error " reset target microcontroller ..."
i understand that bootloader code must be written into PIC but how ...
is there any other bootloader worth trying ?
Don't know...
I figured the BigPic4 had it's own bootloader written into the '8520 that wanted to talk to the BigPic4's software running on the PC, therefore you would have to use that software to talk to the '8520.
I wouldn't think the COM port would work since the board is designed to be programmed thru the USB port.
Sounds to me like the thing is designed to work with BigPic4 software/hardware only...i.e. can't use PicKit2 unless you plug into the correct '8520 pins, can't use MPLAB to tie into the programmer 'cause MPLAB doesn't know about the BigPic4 programmer, and so on...
Like I said, I don't know for sure, I don't use one of those boards.