Monday, September 28, 2020


Cheap ATmega32A alternative at Digikey

The ATmega324PA-PN is the industrial temperature rated version which usually cost more. It is a non-stock item at Digikey and they seem to be trying to get rid of them. At $2.04 each they are much cheaper than the ATmega32A. It is a newer (though still fairly old) generation chip than the ATmega32A. It shares the same pinout. It can also run at up to 20MHz while the ATmega32A runs at 16MHz. 

It is not a drop in replacement. A compiled hex file for the ATmega32 will not run on the ATmega324PA. It will need to be recompiled with the ATmega324PA as the target.

The only modifications I had to make to the 108 code was to change the MCU from atmega32a to atmega324pa and comment out the line that defines the timer register on the ATmega32.

I also compiled a version of the USBaspLoader for the ATmega324PA, same as for the ATmega32, just changing the MCU. The fuses are the same as for the ATmega164.