3.1. Microcontroller

Like other A-Star 32U4 programmable controllers, the A-Star 32U4 Robot Controller features an integrated, USB-enabled ATmega32U4 AVR microcontroller from Atmel, clocked by a precision 16 MHz crystal oscillator. This is the same microcontroller and clock frequency used in the Arduino Leonardo and Arduino Micro.

The board includes a USB Micro-B connector that can be used to connect to a computer’s USB port via a USB A to Micro-B cable (not included). The USB connection can be used to transmit and receive data from the computer and program the board over USB. The USB connection can also provide power for the microcontroller and most of the other hardware on the A-Star (but not motor power); see Section 3.5 for more details.

The robot controller’s ATmega32U4 comes preloaded with the Arduino-compatible A-Star 32U4 USB bootloader, which allows it to be easily programmed using the Arduino IDE. For more information about programming the A-Star 32U4 Robot Controller, see Section 4.

The board also has a 6-pin ISP header that allows it to be programmed with an external programmer, such as our USB AVR programmer. Pin 1 of the header is indicated with a small white dot and has an octagonal shape.