28 lines
1 KiB
Text
28 lines
1 KiB
Text
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= Delaying a Task
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In an embedded program, delaying a task is one of the most common actions taken. In an event loop, delays will need to be inserted to ensure
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that other tasks have a chance to run before the next iteration of the loop is called, if no other I/O is performed. Embassy provides an abstraction
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to delay the current task for a specified interval of time.
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Timing is serviced by the `embassy::time::Timer` struct, which provides two timing methods.
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`Timer::at` creates a future that completes at the specified `Instant`, relative to the system boot time.
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`Timer::after` creates a future that completes after the specified `Duration`, relative to when the future was created.
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An example of a delay is provided as follows:
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[,rust]
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----
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use embassy::executor::{task, Executor};
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use embassy::time::{Duration, Timer};
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#[task]
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/// Task that ticks periodically
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async fn tick_periodic() -> ! {
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loop {
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rprintln!("tick!");
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// async sleep primitive, suspends the task for 500ms.
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Timer::after(Duration::from_millis(500)).await;
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}
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}
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----
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