i have a strange problem with a board based on the atmega644p .. I am able to burn the sanguino bootloader using the arduino as the ISP. Also i am able to upload sketches directly without the bootloader again using the Arduino ISP . But if it try to upload sketches after uploading the bootloader using a FTDI board it gives me a error...

I tried both the arduino 0.23 and the arduino1.0.1 and both the bootloaders.


Any clue what stupid mistake am i making?

there are a few 644p bootloaders about that dont actuly work. And you need the correct one for the correct frequency your runing the chip at (16 or 20 mhz normaly) And since the IDE also sets the fuses, which selects if your using a resinator or a crystal you may also need to play with the boards.txt file to change the fuses.

These are known to work well. [reprap.org]
Ie download and use [github.com] as the boot loader
These are designed for a crystal.

You havent mentioned what board you actuly have...

Edited 4 time(s). Last edit at 12/04/2014 09:50PM by Dust.

@dust

Thanks i will give it a try .. The board is custom made for a small robot..It uses a 16mhz crystall and 22pf capacitors



doodlel293dd.sch

doodlel293dd.brd

Edited 1 time(s). Last edit at 12/04/2014 11:28PM by ekaggrat.

i tried all the bootloaders and none of them work... Maybe i am doing something wrong

Go yout tx and rx correct way around?

load a up a test serial sketcha and the serial monitor on the IDE and mack sure you can send and receive.

bingo !. on serial test i figured that pin 9 had a bad solder.. my mistake .. resoldered and now every bootloader on the block works....