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Topic: How Can I Hack a MEGA 1280 Into a MEGA 2560? (Read 4444 times) previous topic - next topic

TECH GEEK

How can I mod a MEGA 1280 into a MEGA 2560 by un-soldering certian componiants and replaceing them with parts that would make it eqivalent to an Arduino MEGA 2560?
is this possible, and is it a good idea to try?
if it is what would need to be replaced?

                      -THANKS-
                                          -TECH GEEK-
As always... Thanks for posting!!!

CrossRoads

#1
Jan 31, 2011, 05:00 pm Last Edit: Jan 31, 2011, 05:05 pm by CrossRoads Reason: 1
You're looking at replacing the microcontroller itself.
Comparable to pulling an atmega168 out and putting in a 328.

Am sure its doable if you comfortable unsoldering the 1280 and can do so without damaging the pads to install the 2560.
The parts are listed on the same atmel datasheet.

I haven't compared the 2 schematics to see if anything else would need to be done.

Wow - $18 for the 2560!
http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=ATMEGA2560-16AU-ND
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

bilbo

The good news is, I believe the 2560 and 1280 are pin compatible, but here's the issue. As far as I know, its not possible to source a 2560 with the arduino bootloader pre-installed. Thus, you will have to find a way to flash it with the new 2560 bootloader. This should be possible (you can do it with the atmega328), but it will probably be a pain. Lastly, the 2560 bootloader is meant to be programmed from the atmega8u2, but by the schematic, I think it should still be able to be programmed by the ftdi chip (its all just over TTL serial).

I think you already know this, but soldering TQFP is a real pain...maybe just grab a new mega. Besides, at least in my opinion, the best feature of the new mega isnt the new proc but the atmega8u2 instead of FTDI, which you will be stuck with on the 1280 board. It really doesn't seem worth it.

Good luck!
Alice asked the Chesire Cat, who was sitting in a tree, "What road do I take?"
The cat asked, "Where do you want to go?"
"I don't know," Ali

Senso

Gcc can only generate code up to 128k, so using an atmega2560 brings you 0 advantages over the 128, only IAR can generate code for all the atmega2560.

retrolefty

#4
Feb 01, 2011, 07:25 am Last Edit: Feb 01, 2011, 07:27 am by retrolefty Reason: 1

Gcc can only generate code up to 128k, so using an atmega2560 brings you 0 advantages over the 128, only IAR can generate code for all the atmega2560.


I believe that is a incorrect statement. Your getting your flash word size mixed up with the AVR byte capacity rating. The Gcc compiler can indeed fill the atmega2560's 256k bytes of memory with code. Recall that Harvard architecture cpu have separate code memory (flash) and data memory (sram) , and they are not the same width memories in the AVR series.

Most AVR instructions have a single 16-bit word format. Gcc can generate code up to 128k WORDS ( = 256k bytes), so a mega2560 does contain twice the program memory as a mega1280 and Gcc can take advantage of all of it.

Lefty

westfw

Unfortunately: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38549

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