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extern crate cortex_m_rtfm as rtfm;
use rtfm::{CMax, C2, P1, P2, P3, PMax, Resource, T1, T2, T3, TMax};
static R1: Resource<i32, C2> = Resource::new(0);
// You don't need to raise the ceiling to access a resource with ceiling equal
// to the task priority.
fn j1(prio: P2, thr: T2) {
thr.raise(&R1, |_| {});
//~^ error
// OK
let r1 = R1.access(&prio, &thr);
}
// You CAN access a resource with ceiling C from a task with priority P if C > P
// if you raise the preemption threshold first
fn j2(prio: P1, thr: T1) {
// OK
thr.raise(&R1, |thr| { let r1 = R1.access(&prio, thr); })
}
static R2: Resource<i32, CMax> = Resource::new(0);
// Tasks with priority less than P16 can't access a resource with ceiling CMax
fn j4(prio: P1, thr: T1) {
thr.raise(&R2, |thr| {});
//~^ error
}
// Only tasks with priority P16 can directly access a resource with ceiling CMax
fn j5(prio: PMax, thr: TMax) {
// OK
let r2 = R2.access(&prio, &thr);
}
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