[−][src]Crate minimult_cortex_m
This crate for Rust provides a minimal multitask library Minimult
for Cortex-M microcontrollers.
Target
Single-core systems of
- Cortex-M0 / M0+ / M1 (
thumbv6m-none-eabi
) - Cortex-M3 (
thumbv7m-none-eabi
) - Cortex-M4 / M7 (
thumbv7em-none-eabi
) with FPU (thumbv7em-none-eabihf
) - Cortex-M23 (
thumbv8m.base-none-eabi
) - Cortex-M33 / M35P (
thumbv8m.main-none-eabi
) with FPU (thumbv8m.main-none-eabihf
)
Minimult
is still in beta because the author had only a few tests only on Cortex-M4 with FPU.
Features
- Task like that of a typical RTOS
Minimult
can take closures and register them as tasks.Minimult
runs into a loop to start dispatching those tasks.- Not supported: dynamically creating and spawning.
- Synchronization
idle
andkick
- A task goes into an idle state and other tasks/interrupts wake it up by kicking.
MTMsgSender
andMTMsgReceiver
- Task-to-task communication by message passing.
MTSharedCh
- Shared variable among tasks.
- Priority-based dispatching
- A higher priority task preempts lower priority tasks.
- Round-robin dispatching within the same priority tasks.
dispatch
can be directly requested so that timer-based preemption is also possible.
- Static memory allocation
Minimult
doesn't require a global allocator but reserves a bunch of memory block in advance.
Examples
Usage Outline
// Build-only example #![no_main] #![no_std] use cortex_m::Peripherals; use cortex_m_rt::entry; use cortex_m_rt::exception; extern crate panic_semihosting; // other codes... use minimult_cortex_m::*; #[entry] fn main() -> ! { let mut mem = Minimult::mem::<[u8; 4096]>(); let mut mt = Minimult::new(&mut mem, 2); // other codes... let mut q = mt.msgq::<u32>(4); let (snd, rcv) = q.ch(); mt.register(0/*tid*/, 1, 256, || task0(snd)); mt.register(1/*tid*/, 1, 256, || task1(rcv)); // other codes... let cmperi = Peripherals::take().unwrap(); let mut syst = cmperi.SYST; syst.set_clock_source(cortex_m::peripheral::syst::SystClkSource::Core); syst.set_reload(0xffffff); syst.clear_current(); syst.enable_counter(); syst.enable_interrupt(); // other codes... mt.run() } #[exception] fn SysTick() { // other codes... Minimult::kick(0/*tid*/); } fn task0(mut snd: MTMsgSender<u32>) { // other codes... loop { Minimult::idle(); // other codes... let some_value = 1; snd.send(some_value); } } fn task1(mut rcv: MTMsgReceiver<u32>) { // other codes... loop { let mut some_value = 0; rcv.receive(|v| {some_value = *v}); // other codes... } }
Other Examples
You can find a specific board's example here. Currently there are very few examples, however.
Structs
MTMemBlk | Memory block used by |
MTMsgQueue | Message queue for task-to-task communication |
MTMsgReceiver | Message receiving channel |
MTMsgSender | Message sending channel |
MTShared | Shared variable among tasks |
MTSharedCh | Shared variable access channel |
Minimult | Multitasking API |
Type Definitions
MTTaskId | Task identifier |
MTTaskPri | Task priority |