Upgrade to ATmega328?

I’m in the UK and thinking of buying a 3pi. However, none of the distributors here seem to make it clear whether or not the robot comes with a 168 or 328 MCU. Looking around the Pololu website and forums, I haven’t found anything to say whether or not it’s possible to upgrade a 168 to a 328. I’ve done this with an Arduino, and know technically that it’s possible, but can’t find any info as to whether or not there is any proprietary code in the 3pi that I couldn’t transfer to a 328 from a 168.

My guess is that there isn’t and that the library does all the work, but I’d hate to buy a 3pi and find I’m stuck with a 168. Can anyone enlighten me please?

Thanks, Steve.

Hello Steve,

There is nothing proprietary about the AVR we put on the 3pi. However, if you are used to replacing DIP packages, like the one the Arduino Duemilanove has, you will find that it is harder to replace the AVR on the 3pi. The AVR package on the 3pi is surface-mount and would require a hot-air rework station (and SMT soldering experience) to replace.

The easiest thing to do is just contact the distributor you want to buy the 3pi from and have them look at the box. We write the serial number on the outside of the box, and if the serial number is greater than or equal to 5840, the 3pi has a 328P AVR.


Ah… good news on the code, but thanks for the info regarding SMT… I’ve done some work with surface mount but would only upgrade the 3pi as a last resort.


I bought one from active robots last week and it has a 328 microprocessor. I could have just been lucky however.

I have been trying to find a baby orangutan 328 in the uk too, but cannot find one of these. They are all 168. I guess fine for most projects though.