//! Two tasks running at *different* priorities with access to the same resource //! //! ``` //! #![deny(unsafe_code)] //! #![feature(proc_macro)] //! #![no_std] //! //! extern crate cortex_m_rtfm as rtfm; //! extern crate stm32f103xx; //! //! use rtfm::{app, Resource, Threshold}; //! //! app! { //! device: stm32f103xx, //! //! resources: { //! static COUNTER: u64 = 0; //! }, //! //! tasks: { //! // The `SYS_TICK` task has higher priority than `TIM2` //! SYS_TICK: { //! path: sys_tick, //! priority: 2, //! resources: [COUNTER], //! }, //! //! TIM2: { //! path: tim2, //! priority: 1, //! resources: [COUNTER], //! }, //! }, //! } //! //! fn init(_p: init::Peripherals, _r: init::Resources) { //! // .. //! } //! //! fn idle() -> ! { //! loop { //! rtfm::wfi(); //! } //! } //! //! fn sys_tick(_t: &mut Threshold, r: SYS_TICK::Resources) { //! // .. //! //! // This task can't be preempted by `tim2` so it has direct access to the //! // resource data //! **r.COUNTER += 1; //! //! // .. //! } //! //! fn tim2(t: &mut Threshold, mut r: TIM2::Resources) { //! // .. //! //! // As this task runs at lower priority it needs a critical section to //! // prevent `sys_tick` from preempting it while it modifies this resource //! // data. The critical section is required to prevent data races which can //! // lead to undefined behavior. //! r.COUNTER.claim_mut(t, |counter, _t| { //! // `claim_mut` creates a critical section //! **counter += 1; //! }); //! //! // .. //! } //! ``` // Auto-generated. Do not modify.