A brief history so far (Part 3)

My first frustrations with the new G3 Electronics set were the hefty customs charge that the UK pays on good from the states (rip-off!) and the realisation that in order to use it you need to purchase at least a serial controller and possibly a device to load the bootloader onto the board (http://www.ladyada.net/make/usbtinyisp/)!

Two more purchases later (This G3 set was starting to look expensive already) and I was ready to begin.

Built serial board as described here (http://reprap.org/wiki/Mendel_USB_and_power_connector) connected to RepRap Motherboard V1.2 as described and began trying to get comms with Motherboard, Nothing not a dickybird.

Guessing that my board had been supplied with no bootloader loaded I switched to building the USBTinyISP programmer (comes in kit form with PIC preloaded thankfully) preying that my soldering skills would not let me down.

Attempted to load bootloader, more web research required, using AVRDude tried several times eventually got the success message, Great (I thought) still no life from the board though, no lights, nothing. (beginning to wonder if board is a dud) more web research later and I discover that the chip on my board is a 644 not a 644P maybe I am using the wrong bootloader, check bootloader file, Sure enough its wrong and not only that I had copied the bootloader hex directly out of a webpage rather than downloading the file (shoddy!) and inadvertently the whole file was full of return carriage’s (extra characters at end of each line) guessing that this was probably going to upset things a little, I searched the web for a 644 (non 'P') bootloader hex file, found one downloaded correctly this time and flashed using AVRdude and voila "it’s alive" (yes I was leaping around shouting "it's alive" in my best Frankenstein voice) as denoted by the flashing debug led on start-up (flashes 3 times pause and then 4th flash)

Great (I Thought) surely now the serial comms issue would be solved (NOT) same message as before!

"avrdude: stk500_getsync(): not in sync: resp=0x00 avrdude: stk500_disable(): protocol error"

Still no comms!

During one of the many web research's required to get me to this point I had done some reading on using AVRdude to flash bootloaders and seemed to remember something about setting fuses, found a relevant webpage

http://forums.reprap.org/read.php?4,91699

It mentions that out the box the Mega644 chip runs at 1mhz and to get it to use the on-board crystal you need to “set the fuses”, not knowing much about setting fuses (and worrying that I might accidentally set something that I can’t unset) I thought that now I have serial comms established I may now be able to use Arduino IDE to flash the bootloader (hoping that Arduino IDE might set the fuses correctly automatically without me having to get technical with the command line) first try worked like a treat, same 3 flashes pause and 4th flash but this time a lot faster.

Bootloader DONE, hurrah!