【转】STM8的福利--Atomthreads实时操作系统

只看该作者 · 2016-11-27 13:24

Atomthreads是开源的实时操作系统。诞生之初就是给STM8s设计的，而且作者还在不断更新，我看最近的主要修改是加入更多MCU的支持。算法上没有变化。所以我取了1.3的版本，足够用了。
我使用的是STM8S105K4的最小系统。有16Kflash可以使用。这个大小放下原生的atomthreads是够的。

这个实时系统包含了操作系统所有最基本的接口

mutex
semaphore
timer
queue
255级优先级的强占是调度
同优先级时间片轮转

等等。绝对算是完整的操作系统。

并且源代码有所有API调用的例子，这绝对是福利，节约大家时间。要造汽车，绝对不需要每次都从车轮造起。当今世界要站在巨人的肩膀上前进。

回到atomthreads的内部，它需要一个心跳timer，系统默认使用了TIM1这个STM8中功能最强的timer。如果你的系统中要用TIM1做更复杂的事情，那么你可以改用其他的TIM2/TIM3来做心跳。

[cpp] view plain copy

NO_REG_SAVE void main ( void )
{
int8_t status;
/**
* Note: to protect OS structures and data during initialisation,
* interrupts must remain disabled until the first thread
* has been restored. They are reenabled at the very end of
* the first thread restore, at which point it is safe for a
* reschedule to take place.
*/
/* Initialise the OS before creating our threads */
status = atomOSInit(&idle_thread_stack[IDLE_STACK_SIZE_BYTES - 1], IDLE_STACK_SIZE_BYTES);
if (status == ATOM_OK)
{
/* Enable the system tick timer */
archInitSystemTickTimer();
/* Create an application thread */
status = atomThreadCreate(&main_tcb,
TEST_THREAD_PRIO, main_thread_func, 0,
&main_thread_stack[MAIN_STACK_SIZE_BYTES - 1],
MAIN_STACK_SIZE_BYTES);
if (status == ATOM_OK)
{
/**
* First application thread successfully created. It is
* now possible to start the OS. Execution will not return
* from atomOSStart(), which will restore the context of
* our application thread and start executing it.
*
* Note that interrupts are still disabled at this point.
* They will be enabled as we restore and execute our first
* thread in archFirstThreadRestore().
*/
atomOSStart();
}
}
/* There was an error starting the OS if we reach here */
while (1)
{
}
}