Arduino Robot 4 Atmega32u4-** chips?

[Poofjunior]

Hi everyone; I was looking at the schematic and noticed that each schematic (control_board_v006_Rev5.1 and Motor_Board-Rev5.2.b.1) both have two Atmega32u4's on them. These chips have different "sufffixes,": -MU and -AU so I'm assuming that they're two disctinct chips with two packages.

Are there actually four Atmega32u4's on the Arduino Robot?

For reference, the schematics can be found: here

[Poofjunior]

Whoop--one quick look at the actual hardware solved this problem. to answer my own question, it looks like either an ATMega32u4-MU or an ATMega32u4-AU may be soldered onto the board as the primary microcontroller.

I'm assuming that a shortage of *-AUs would just prompt the robot board manufacturers to switch to the *-MU package, or vice versa. This "feature" ends up looking like two ATMega32u4s are on each board, which is a bit misleading.