Minor docs update to monotonic
@@ -128,10 +128,12 @@ pub struct Fraction {
/// A monotonic clock / counter
pub trait Monotonic {
- /// A measurement of this clock
+ /// A measurement of this clock, use `CYCCNT` as a reference implementation for `Instant`.
+ /// Note that the Instant must be a signed value such as `i32`.
type Instant: Copy + Ord + Sub;
- /// The ratio between the SysTick (system timer) frequency and this clock frequency
+ /// The ratio between the system timer (SysTick) frequency and this clock frequency, i.e.
+ /// `Monotonic clock * Fraction = System clock`
///
/// The ratio must be expressed in *reduced* `Fraction` form to prevent overflows. That is
/// `2 / 3` instead of `4 / 6`
