Introduction

Author: Marius Nicolae, Microchip Technology Inc.

The tinyAVR^® 0-series, tinyAVR 1-series and megaAVR^® 0-series of microcontrollers are equipped with powerful timers that enable them to cover a wide area of applications. Timer/Counter Type B (TCB) offers a variety of features and operation modes, from periodic interrupts to 8-bit PWM or time-out. The various operation modes of the TCB can be used in correlation with the event system. The scope of this technical brief is to show the configuration of three operation modes.

Using TCB in 8-bit PWM mode:
TCB will be configured in this mode and will generate a PWM signal with a 50% duty cycle for a 1-second period. A GPIO pin will be used as an output to showcase the signal.
Using TCB in Time-Out Check mode:
TCB will be configured in this mode and will be used to measure the signal time (edge-to-edge) generated by a GPIO pin configured as input. An interrupt will be generated if the time-out (period from edge-to-edge) expires.
Using TCB in Sleep mode:
TCB will be configured to generate a periodic interrupt, even when the AVR^® microcontroller is in Standby Sleep mode.

Note: In each example, GPIOs are used either for input (event system input signal), or for output (e.g. toggling a pin each time an interrupt occurs). The code examples were developed using the ATmega4809 Xplained Pro (ATMEGA4809-XPRO) development board, but are suitable for the entire tinyAVR 0-series, tinyAVR 1-series and megaAVR 0-series.