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extern crate cortex_m_rtfm as rtfm;
use rtfm::{C16, C2, P1, P16, P2, P3, Resource};
static R1: Resource<i32, C2> = Resource::new(0);
// You CAN'T use `raise` to lower the system ceiling
fn j1(prio: P3) {
let ceil = prio.as_ceiling();
ceil.raise(&R1, |ceil| {});
//~^ error
}
// You don't need to raise the ceiling to access a resource with ceiling equal
// to the task priority.
fn j2(prio: P2) {
let ceil = prio.as_ceiling();
ceil.raise(&R1, |_| {});
//~^ error
// OK
let r1 = R1.access(&prio, ceil);
}
// You CAN access a resource with ceiling C from a task with priority P if C > P
// and you raise the ceiling first
fn j3(prio: P1) {
let ceil = prio.as_ceiling();
// OK
ceil.raise(&R1, |ceil| { let r1 = R1.access(&prio, ceil); })
}
static R2: Resource<i32, C16> = Resource::new(0);
// Tasks with priority less than P16 can't access a resource with ceiling C16
fn j4(prio: P1) {
let ceil = prio.as_ceiling();
ceil.raise(&R2, |ceil| {});
//~^ error
}
// Only tasks with priority P16 can access a resource with ceiling C16
fn j5(prio: P16) {
// OK
let r2 = R2.access(&prio, prio.as_ceiling());
}
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