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meho
- 21st February 2008, 21:00
hi guys,
desperatelly seeking the way how to convince my system start working with microcode loader :

-Bigpic 4 board from mikroelektronika (pic18f8520,ICD,USB on board programmer...)
works good with their own soft i.e. mikroBasic 6 and PicFlash programmer but..

i heavily tried microcode studio with picbasic and RS 232 connection to COM1- correct settings for MPASM, PB ,microcode loader but with no success -all i get is

-"reset required... pls reset the target microcontroller to access the bootloader process"
Could it be some trouble with serial port (COM1) -winxp device manager says it is OK ?

(resulting compiled hex file can be correctly written to pic with USB - Picflash programmer !?

Any idea what am i doing wrong?

thanx for your help

skimask
- 21st February 2008, 21:17
hi guys,
desperatelly seeking the way how to convince my system start working with microcode loader :
-Bigpic 4 board from mikroelektronika (pic18f8520,ICD,USB on board programmer...)
works good with their own soft i.e. mikroBasic 6 and PicFlash programmer but..
i heavily tried microcode studio with picbasic and RS 232 connection to COM1- correct settings for MPASM, PB ,microcode loader but with no success -all i get is
-"reset required... pls reset the target microcontroller to access the bootloader process"
Could it be some trouble with serial port (COM1) -winxp device manager says it is OK ?
(resulting compiled hex file can be correctly written to pic with USB - Picflash programmer !?
Any idea what am i doing wrong?
thanx for your help

Did you reprogram the '8520 on the BigPic4 board with your own bootloader?

meho
- 22nd February 2008, 09:42
Did you reprogram the '8520 on the BigPic4 board with your own bootloader?

thanks for question and interest :

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 ?


have a nice day

skimask
- 22nd February 2008, 13:54
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.

rdphoto
- 9th August 2012, 14:39
The post is four years old, but others who come upon this should know the Microcode loader is to program PICs that already have the boot loader programmed into them. The boot loader runs first on a RESET and checks to see if the Microcode loader application on the PC is trying to communicate on a UART port and if communication is established programming can continue. Otherwise, the boot loader exits and the existing application code in the PIC starts up (if it is there). This is why your Microcode loader is asking for a RESET.

Bootloader code is available for one-time purchase (no royalty) from http://www.mecanique.co.uk/products/pic-prog/bootloader.html
A free bootloader is ds30 loader but I have found this hard to configure under HI-TECH C compiler. Seems to be too many errors. But I am not very experienced so your mileage may vary.

You must first program the boot loader code using a regular programmer. Use the programmer on the BigPic4 board, for example. From then on out use the Microcode loader but tied to UART. You might need an FTDI cable that converts USB to UART (RS232) at 5v or 3v logic. Example: https://www.sparkfun.com/products/9717