Yaroslav Barabanov
Here, alternative functions and classes for STM32. The program contains a class for the I2C software bus, a class for working with a watchdog timer and time delay functions based on DWT. All functions and classes use the HAL library. Functions and classes were written for the microcontroller stm32f103.
Dependents: STM32_F1XX_Alternative
Diff: AlternativeDelay.cpp
- Revision:
- 0:2f819bf6cd99
- Child:
- 1:0d39ea4dee8b
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/AlternativeDelay.cpp Wed May 24 19:04:12 2017 +0000
@@ -0,0 +1,42 @@
+#include "AlternativeDelay.hpp"
+#include "stm32f1xx_hal.h"
+#include "mbed.h"
+
+#define DWT_CYCCNT *(volatile unsigned long *)0xE0001004
+#define DWT_CONTROL *(volatile unsigned long *)0xE0001000
+#define SCB_DEMCR *(volatile unsigned long *)0xE000EDFC
+
+static bool isInitializationDWT = false;
+
+void initializationDWT(void) {
+ // allow to use the counter
+ SCB_DEMCR |= CoreDebug_DEMCR_TRCENA_Msk;
+ // zero the value of the register register
+ DWT_CYCCNT = 0;
+ // start the counter
+ DWT_CONTROL |= DWT_CTRL_CYCCNTENA_Msk;
+ isInitializationDWT = true;
+}
+
+void initializeTimeDelays(void) {
+ initializationDWT();
+}
+
+static __inline uint32_t delta(uint32_t t0, uint32_t t1) {
+ return (t1 - t0);
+}
+
+void delay_us(uint32_t us) {
+ uint32_t t0 = DWT->CYCCNT;
+ uint32_t us_count_tic = us * (SystemCoreClock/1000000);
+ while (delta(t0, DWT->CYCCNT) < us_count_tic) ;
+}
+
+void delay_ms(uint32_t ms) {
+ if (isInitializationDWT == false) {
+ initializationDWT();
+ }
+ uint32_t t0 = DWT->CYCCNT;
+ uint32_t us_count_tic = ms * (SystemCoreClock/1000000);
+ while (delta(t0, DWT->CYCCNT) < us_count_tic) ;
+}
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