Monotonic book

book/en/src/by-example/tips_monotonic_impl.md

@@ -1,35 +1,29 @@
 # Implementing a `Monotonic` timer for scheduling
 
-The framework is flexible because it can use any timer which has compare-match and optionally
+The framework is flexible because it can use any timer which has compare-match and optionally supporting overflow interrupts for scheduling. The single requirement to make a timer usable with RTIC is implementing the [`rtic-time::Monotonic`] trait.
-supporting overflow interrupts for scheduling.
-The single requirement to make a timer usable with RTIC is implementing the
-[`rtic_monotonic::Monotonic`] trait.
 
-Implementing time counting that supports large time spans is generally **difficult**, in RTIC 0.5
+For RTIC 1.0 and 2.0 we instead assume the user has a time library, e.g. [`fugit`] or [`embedded_time`], as the basis for all time-based operations when implementing `Monotonic`. These libraries make it much easier to correctly implement the `Monotonic` trait, allowing the use of
-implementing time handling was a common problem.
-Moreover, the relation between time and timers used for scheduling was difficult to understand.
-
-For RTIC 1.0 we instead assume the user has a time library, e.g. [`fugit`] or [`embedded_time`],
-as the basis for all time-based operations when implementing `Monotonic`.
-These libraries make it much easier to correctly implement the `Monotonic` trait, allowing the use of
 almost any timer in the system for scheduling.
 
-The trait documents the requirements for each method,
+The trait documents the requirements for each method, and for inspiration
-and for inspiration here is a list of `Monotonic` implementations:
+there is a reference implementation based on the `SysTick` timer available on all ARM Cortex M MCUs. 
+
+- [`Systick based`], runs at a fixed interrupt (tick) rate - with some overhead but simple and provides support for large time spans
+
+Here is a list of `Monotonic` implementations for RTIC 1.0:
 
 - [`STM32F411 series`], implemented for the 32-bit timers
 - [`Nordic nRF52 series Timer`], implemented for the 32-bit timers
 - [`Nordic nRF52 series RTC`], implemented for the RTCs
-- [`Systick based`], runs at a fixed interrupt (tick) rate - with some overhead but simple and with support for large time spans
 - [`DWT and Systick based`], a more efficient (tickless) implementation - requires both `SysTick` and `DWT`, supports both high resolution and large time spans
 
 If you know of more implementations feel free to add them to this list.
 
-[`rtic_monotonic::Monotonic`]: https://docs.rs/rtic-monotonic/
+[`rtic_time::Monotonic`]: https://docs.rs/rtic_time/
 [`fugit`]: https://docs.rs/fugit/
 [`embedded_time`]: https://docs.rs/embedded_time/
 [`STM32F411 series`]: https://github.com/kalkyl/f411-rtic/blob/a696fce7d6d19fda2356c37642c4d53547982cca/src/mono.rs
 [`Nordic nRF52 series Timer`]: https://github.com/kalkyl/nrf-play/blob/47f4410d4e39374c18ff58dc17c25159085fb526/src/mono.rs
 [`Nordic nRF52 series RTC`]: https://gist.github.com/korken89/fe94a475726414dd1bce031c76adc3dd
-[`Systick based`]: https://github.com/rtic-rs/systick-monotonic
+[`Systick based`]: https://github.com/rtic-monotonics
 [`DWT and Systick based`]: https://github.com/rtic-rs/dwt-systick-monotonic