25.8.4 Quick Start Guide for TCC - Callback

The supported board list:

  • SAM D21/R21/L21/L22/DA1/C21 Xplained Pro

In this use case, the TCC will be used to generate a PWM signal, with a varying duty cycle. Here the pulse width is increased each time the timer count matches the set compare value. When connect PWM output to LED it makes the LED vary its light. To see the waveform, you may need an oscilloscope.

The PWM output is set up as follows:

Board

Pin

Connect to

SAMD21 Xpro

PB30

LED0

SAMR21 Xpro

PA19

LED0

SAML21 Xpro

PB10

LED0

SAML22 Xpro

PC27

LED0

SAMDA1 Xpro

PB30

LED0

SAMC21 Xpro

PA15

LED0

The TCC module will be set up as follows:

  • GCLK generator 0 (GCLK main) clock source

  • Use double buffering write when set top, compare, or pattern through API

  • No dithering on the counter or compare

  • No prescaler

  • Single Slope PWM wave generation

  • GCLK reload action

  • Don't run in standby

  • No faults or waveform extensions

  • No inversion of waveform output

  • No capture enabled

  • Count upward

  • Don't perform one-shot operations

  • No event input enabled

  • No event action

  • No event generation enabled

  • Counter starts on 0