Oh yeah, I already saw a concept like this. Except it was an arduino programming another! Interesting.
I was reasoning with Arduino. From navigating 2 hours per day here (and more) I see alot of people warning others about load.
On the Arduino, each pins can run a maximum 40mA and 300 mA in total. Even then, I think these are stress value that shouldn't be experienced with or you could destroy a pin or potentionally the IC.
I don't about your Specs, just be sure everything is okay with the datasheet or ask somebody else that know a little more about microcontroller than me.