imxrt_hal

Module timer

Source
Expand description

General timer APIs.

timer provides adapters for implementing (non-)blocking timers. It builds upon hardware drivers like gpt and pit, and implements various embedded-hal timer traits.

Use Blocking to adapt a timer for simple, blocking delays. Blocking delays use durations, not raw clock ticks; this means that you need to specify the clock’s frequency.

Use CountDown to adapt a timer for periodic, non-blocking time tracking. This also uses time duration, not raw clock ticks, for timing, so it again needs the clock frequency. Use RawCountDown if you want to track time in clock ticks.

§Raw count representations

The raw count, or ticks, supported by the driver influences the API. The table below describes the raw bit width for each adapter.

DriverBit width
PIT channel32
PIT chain64
GPT32

§Computing the clock frequency

ccm APIs make it easy to understand, at compile time, the intended clock frequency for a given timer. Consider using these to simply compute the clock frequency. See the Blocking and CountDown examples for demonstrations.

This package does not provide an implementation of Cancel from embedded-hal 0.2. See RawCountDown documentation for more information.

§Limitations of CountDown

This module cannot provide the embedded-hal 0.2 CountDown implementation for all possible drivers. You’re encouraged to adapt RawCountDown to implement a CountDown implementation for your specific driver.

Structs§

  • Blocking
    A blocking timer that runs at HZ.
  • CountDown
    A count down timer adapter that uses fugit durations.
  • RawCountDown
    A count down timer that uses ticks for the timeout.

Type Aliases§