István Cserny
Using ADC interrupts in RTOS environment. This program also demonstrates the usage of RTOS API function calls from interrupt.
Revision 0:b6055a7af0c9, committed 2022-04-10
- Comitter:
- cspista
- Date:
- Sun Apr 10 12:20:27 2022 +0000
- Commit message:
- Final version
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Sun Apr 10 12:20:27 2022 +0000
@@ -0,0 +1,61 @@
+#include "mbed.h"
+#include "rtos.h"
+AnalogIn adc(A4);
+DigitalOut led1(LED1);
+
+typedef uint32_t message_t;
+Queue <message_t, 4> queue;
+
+void led1_thread(void const *args)
+{
+ while (true) {
+ led1 = !led1;
+ Thread::wait(1000);
+ }
+}
+
+//--- ADC Interrupt handler -----------------
+extern "C" void ADC1_IRQHandler()
+{
+ NVIC_ClearPendingIRQ(ADC_IRQn); //Clear ADC Interrupt Request Flag
+ uint16_t raw = ADC1->DR;
+ queue.put((message_t*)raw); //Send result through a Queue
+}
+
+//--- Start conversion, wait for result -----
+uint16_t adc_read(uint32_t ch)
+{
+ ADC1->SQR3 = ch; //set conversion channel
+ ADC1->SMPR2 = 7; //Sample time =480
+ ADC1->CR1 |= ADC_CR1_EOCIE; //enable interrupt
+ ADC1->CR2 |= ADC_CR2_SWSTART; //Start conversion
+ osEvent evt = queue.get(); //Wait for a message
+ return (uint16_t)evt.value.v; //Return obtained value
+}
+
+int main()
+{
+ int32_t v25 = 760; //Voltage at 25C (in millivolts)
+ float m = 2.5; //Slope mV per degree)
+ uint16_t dummy = adc.read(); //needed for ADC configuration
+ ADC123_COMMON->CCR |= ADC_CCR_TSVREFE; //Enable inner channels
+ NVIC_SetVector(ADC_IRQn,(uint32_t)&ADC1_IRQHandler); //Attach ADC ISR
+ NVIC_EnableIRQ(ADC_IRQn); //Enable ADC interrupts
+ Thread thread1(led1_thread);
+ printf("\r\n Lab09 ADC interrupt in RTOS environment\r\n");
+ while(true) {
+ uint32_t a1 = 0;
+ uint32_t a2 = 0;
+ for(int i=0; i<3300; i++) {
+ a1 += adc_read(11); //Measure voltage at A4 (PTC_1)
+ a2 += adc_read(18); //Internal temperature sensor
+ }
+ float v1 = a1/4096.0f; //Convert v1 to millivolts
+ float temp1 = (v1-500)/10.0; //MCP9700 temperature in Celsius
+ float v2 = a2/4096.0f; //Convert v2 to millivolts
+ float temp2 = 25.0f+(v2-v25)/m; //Calculate temp in Celsius
+ printf("A4 = %.0f mV Temp = %.1f C Inner Ts: %.0f mV Temp = %.1f C\r\n",v1,temp1,v2,temp2);
+ Thread::wait(2000);
+ }
+
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed-rtos.lib Sun Apr 10 12:20:27 2022 +0000 @@ -0,0 +1,1 @@ +https://os.mbed.com/users/mbed_official/code/mbed-rtos/#5713cbbdb706
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Sun Apr 10 12:20:27 2022 +0000 @@ -0,0 +1,1 @@ +https://os.mbed.com/users/mbed_official/code/mbed/builds/65be27845400 \ No newline at end of file