hobbielektronika / Mbed 2 deprecated 11_rtos_queue

Simple example to use a Queue object to send integer data from thread1 to thread2.

Dependencies:   mbed-rtos mbed

main.cpp@0:95dae97a932f, 2016-02-23 (annotated)

Committer:
icserny
Date:
Tue Feb 23 13:34:02 2016 +0000
Revision:
0:95dae97a932f
First version

Who changed what in which revision?

UserRevisionLine numberNew contents of line
icserny 0:95dae97a932f 1 /** 10_rtos_queue
icserny 0:95dae97a932f 2 *
icserny 0:95dae97a932f 3 * Simple example to use a Queue object to send integer data
icserny 0:95dae97a932f 4 * from thread1 to thread2. Note that Queue's put() method is
icserny 0:95dae97a932f 5 * intended to send a pointer, therefore typecasting
icserny 0:95dae97a932f 6 * should be appliedin in order to avoid compiler error messages.
icserny 0:95dae97a932f 7 */
icserny 0:95dae97a932f 8
icserny 0:95dae97a932f 9 #include "mbed.h"
icserny 0:95dae97a932f 10 #include "rtos.h"
icserny 0:95dae97a932f 11
icserny 0:95dae97a932f 12 AnalogIn potmeter(A0);
icserny 0:95dae97a932f 13 PwmOut myled(LED_BLUE);
icserny 0:95dae97a932f 14
icserny 0:95dae97a932f 15 typedef uint32_t message_t;
icserny 0:95dae97a932f 16 Queue<message_t, 16> queue;
icserny 0:95dae97a932f 17
icserny 0:95dae97a932f 18 void led_thread(void const *argument)
icserny 0:95dae97a932f 19 {
icserny 0:95dae97a932f 20 myled.period_us(16384); //Set period to 16.384 ms
icserny 0:95dae97a932f 21 myled.pulsewidth_us(8192); //Initialize to 50% duty cycle
icserny 0:95dae97a932f 22 while (true) {
icserny 0:95dae97a932f 23 osEvent evt = queue.get(); //Wait for a message
icserny 0:95dae97a932f 24 switch(evt.status) {
icserny 0:95dae97a932f 25 case osOK:
icserny 0:95dae97a932f 26 printf("osOK\n"); //no error, no message arrived
icserny 0:95dae97a932f 27 break;
icserny 0:95dae97a932f 28 case osEventMessage:
icserny 0:95dae97a932f 29 printf("osEventMessage = %#05x\n",evt.value.v); //message arrived
icserny 0:95dae97a932f 30 //Note that evt.value is a union.
icserny 0:95dae97a932f 31 //Read as value.v to get a data, or value.p to get a pointer...
icserny 0:95dae97a932f 32 myled.pulsewidth_us((int)(evt.value.v>>2)); //roughly 0..16 ms
icserny 0:95dae97a932f 33 break;
icserny 0:95dae97a932f 34 case osEventTimeout:
icserny 0:95dae97a932f 35 printf("osEventTimeout\n"); //timeout occurred
icserny 0:95dae97a932f 36 break;
icserny 0:95dae97a932f 37 case osErrorParameter:
icserny 0:95dae97a932f 38 printf("osErrorParameter\n");
icserny 0:95dae97a932f 39 break; //invalid parameter or is out of range.
icserny 0:95dae97a932f 40 default:
icserny 0:95dae97a932f 41 printf("Unknown error flag: %#08x\n",(uint32_t)evt.status);
icserny 0:95dae97a932f 42 break;
icserny 0:95dae97a932f 43 };
icserny 0:95dae97a932f 44 }
icserny 0:95dae97a932f 45 }
icserny 0:95dae97a932f 46
icserny 0:95dae97a932f 47 int main (void)
icserny 0:95dae97a932f 48 {
icserny 0:95dae97a932f 49 Thread thread2(led_thread);
icserny 0:95dae97a932f 50
icserny 0:95dae97a932f 51 while (true) {
icserny 0:95dae97a932f 52 Thread::wait(1000);
icserny 0:95dae97a932f 53 uint16_t raw = potmeter.read_u16(); // read raw 16-bit data
icserny 0:95dae97a932f 54 queue.put((message_t*)raw);
icserny 0:95dae97a932f 55 }
icserny 0:95dae97a932f 56 }