Felipe Neves
/
lpc4337_mbed_os_thread_demo
Threading of mbed os running in LPC4337 xplorer kit
main.cpp
- Committer:
- uLipe
- Date:
- 2016-09-26
- Revision:
- 0:da8a31f3e0f7
File content as of revision 0:da8a31f3e0f7:
/** * @brief Simple threading using the mbed os demo */ #include "mbed.h" #include "rtos.h" #include "ST7567.h" /* LCD and font parameters */ #define LCD_HEIGHT 64 #define LCD_WIDTH 128 #define FONT_HEIGHT 10 #define FONT_WIDTH 5 /* allocate statically stacks for the three threads */ unsigned char rt_stk[1024]; unsigned char hp_stk[1024]; unsigned char lp_stk[1024]; /* creates three tread objects with different priorities */ Thread real_time_thread(osPriorityRealtime, 1024, &rt_stk[0]); Thread high_prio_thread(osPriorityHigh, 1024, &hp_stk[0]); Thread low_prio_thread(osPriorityNormal, 1024, &lp_stk[0]); /* create a semaphore to synchronize the threads */ Semaphore sync_sema; /* creates a instance of display */ ST7567 disp(D11, D13, D12, D9, D10); /** * @brief real time prio task function */ static void rt_task(void) { const char rt_message[] = {"Real time prio Task: \0"}; disp.locate(0, FONT_HEIGHT * 2); disp.printf(rt_message); for(;;) { /* take the semaphore allowing less priority * tasks to run */ disp.locate(LCD_WIDTH - (sizeof(rt_message) * FONT_WIDTH), FONT_HEIGHT * 2); disp.printf("WAIT!"); sync_sema.wait(0); /* show the message by 1 second */ disp.locate(LCD_WIDTH - (sizeof(rt_message) * FONT_WIDTH), FONT_HEIGHT * 2); disp.printf("EXEC!"); disp.locate(LCD_WIDTH - (sizeof(rt_message) * FONT_WIDTH), FONT_HEIGHT * 2); disp.printf("DELAY"); Thread::wait(50); } } /** * @brief high prio task function */ static void hp_task(void){ const char hp_message[] = {"High priority Task: \0"}; disp.locate(0, FONT_HEIGHT * 3); disp.printf(hp_message); for(;;) { /* take the semaphore allowing less priority * tasks to run */ disp.locate(LCD_WIDTH - (sizeof(hp_message) * FONT_WIDTH), FONT_HEIGHT * 3); disp.printf("WAIT!"); sync_sema.wait(0); /* show the message by 1 second */ disp.locate(LCD_WIDTH - (sizeof(hp_message) * FONT_WIDTH), FONT_HEIGHT * 3); disp.printf("EXEC!"); disp.locate(LCD_WIDTH - (sizeof(hp_message) * FONT_WIDTH), FONT_HEIGHT * 3); disp.printf("DELAY"); Thread::wait(50); } } /** * @brief normal prio task function */ static void np_task(void) { const char lp_message[] = {"Low priority Task: \0"}; disp.locate(0, FONT_HEIGHT * 4); disp.printf(lp_message); for(;;) { /* show the message by 1 second */ disp.locate(LCD_WIDTH - (sizeof(lp_message) * FONT_WIDTH), FONT_HEIGHT * 4); disp.printf("EXEC!"); disp.locate(LCD_WIDTH - (sizeof(lp_message) * FONT_WIDTH), FONT_HEIGHT * 4); disp.printf("DELAY"); Thread::wait(50); /* release the semaphore and syncrhonize the tasks */ disp.locate(LCD_WIDTH - (sizeof(lp_message) * FONT_WIDTH), FONT_HEIGHT * 4); disp.printf("WAIT!"); sync_sema.release(); } } /** * @brief main loop */ int main(void) { const char banner[] = {"Embarcados MBED-OS Thread demo\0"}; /* configures the display */ disp.cls(); disp.set_contrast(0x35); disp.locate((LCD_WIDTH - (sizeof(banner) * FONT_WIDTH)) / 2, 0); disp.printf(banner); /* starts the three tasks */ real_time_thread.start(rt_task); high_prio_thread.start(hp_task); low_prio_thread.start(np_task); return 0; }