SBAS645 August 2019 DRV5057-Q1
PRODUCTION DATA.
If a capture and compare timer is not available, a standard timer interrupt and a counter can be used. Configure the timer interrupt to be significantly faster than the period of the PWM, based on the desired resolution. Count how many times the timer interrupts while the signal is high (OnTime), then count how many times the timer interrupts while the signal is low (OffTime). Then use Equation 1 to calculate the duty cycle.