diff options
Diffstat (limited to 'src/cyccnt.rs')
| -rw-r--r-- | src/cyccnt.rs | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/src/cyccnt.rs b/src/cyccnt.rs index 468aa712..c8a1b7ee 100644 --- a/src/cyccnt.rs +++ b/src/cyccnt.rs @@ -10,9 +10,15 @@ use core::{ use cortex_m::peripheral::DWT; +use crate::Fraction; + /// A measurement of the CYCCNT. Opaque and useful only with `Duration` /// /// This data type is only available on ARMv7-M +/// +/// Note that this value is tied to the CYCCNT of one core and that sending it a different core +/// makes it lose its meaning -- each Cortex-M core has its own CYCCNT counter and these are usually +/// unsynchronized and they may even be running at different frequencies. #[derive(Clone, Copy, Eq, PartialEq)] pub struct Instant { inner: i32, @@ -21,7 +27,6 @@ pub struct Instant { unsafe impl Sync for Instant {} -#[cfg(not(feature = "heterogeneous"))] unsafe impl Send for Instant {} impl Instant { @@ -182,15 +187,16 @@ impl U32Ext for u32 { } /// Implementation of the `Monotonic` trait based on CYCle CouNTer -#[cfg(not(feature = "heterogeneous"))] pub struct CYCCNT; -#[cfg(not(feature = "heterogeneous"))] impl crate::Monotonic for CYCCNT { type Instant = Instant; - fn ratio() -> u32 { - 1 + fn ratio() -> Fraction { + Fraction { + numerator: 1, + denominator: 1, + } } unsafe fn reset() { |