When not in DEBUG_APP mode, a sample application is provided to allow manual control of the PWM channels via an USART. In the example, commands are sent to USART via the "ATmega328PB Xplained Mini" via the "Atmel Studio", "Data Visualizer", "Serial Port" tool in ASCII format:
#nHH
where:
# is a synchronization character n = 0-9 indicating the required channel number HH = hex value corresponding to 0-255 for PWM high period
A successful command receives the response “OK” whereas an incorrect command will respond with “ERR”. This protocol could easily be adapted to allow an AVR to be used as a slave PWM controller attached to another microcontroller and to allow more channels to be controlled.
Figure 1. Data Visualizer USART
Communication Session