hey guys i was just wondering could it be possible to build a stand alone arduino using atmega128A -AU ? i already purchased the board with a breakout board, googled around for a while but couldnt find any hint. what i try to do is to operate a mega like board using 3.3volts and i dont want to hack my original mega2650 so i thought why couldnt i build one as i did with the barebone uno+FDTI cabel. so schematics and bootloader is what i seek and it would be pretty much appreciated if someone explains how to edit arduino boards.txt as well. cheers
I'm curious also. I have a 40 pin PDIP 128 chip that I'd like to put to use.
i have managed to get the board.txt mod and the make file but i am stuck at pin_arduino.h as i have no clue how to mod it to suid the pins of the atmega128A chip, any help ?? :roll_eyes:
The original "Wiring" board was based on an ATmega128; I think their libraries still support it. http://wiring.org.co/hardware/previous.html See also http://avr-developers.com and http://www.soc-robotics.com/product/Amber_Specs/Amber_Processor.html
I don't think there is any support in the Arduino core (ie pins_arduino.h) for m128, though some of the functions should work due to the general-ification that has been done in recent releases (checking for the existence of a UART1, instead of checking for a particular processor type that then implies the existence of UART1.)
pins_arduino.h is less about the pins on the chip, and more about the pins on the board you are using. To get a particular m128 board working, you'll have to write your own pins_arduino.h file, and to do that you'll have to figure out how it works. It's not too hard; it simply contains the definitions for a bunch of arrays that map from the "pin numbers" used in calls like digitalWrite() to the ports and bits that the processor actually needs to manipulate those pins...