[−][src]Trait embedded_hal::timer::CountDown
A count down timer
Contract
self.start(count); block!(self.try_wait());
MUST block for AT LEAST the time specified bycount
.
Note that the implementer doesn't necessarily have to be a downcounting timer; it could also be an upcounting timer as long as the above contract is upheld.
Examples
You can use this timer to create delays
extern crate embedded_hal as hal; #[macro_use(block)] extern crate nb; use hal::prelude::*; fn main() { let mut led: Led = { // .. }; let mut timer: Timer6 = { // .. }; Led.on(); timer.try_start(1.s()).unwrap(); block!(timer.try_wait()); // blocks for 1 second Led.off(); }
Associated Types
type Error
An enumeration of CountDown
errors.
For infallible implementations, will be Infallible
type Time
The unit of time used by this timer
Required methods
fn try_start<T>(&mut self, count: T) -> Result<(), Self::Error> where
T: Into<Self::Time>,
T: Into<Self::Time>,
Starts a new count down
fn try_wait(&mut self) -> Result<(), Self::Error>
Non-blockingly "waits" until the count down finishes
Contract
- If
Self: Periodic
, the timer will start a new count down right after the last one finishes. - Otherwise the behavior of calling
try_wait
after the last call returnedOk
is UNSPECIFIED. Implementers are suggested to panic on this scenario to signal a programmer error.