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[NUCLEO_L152RE] Change us_ticker timer (32-bit one)

pull/177/head
bcostm 2014-02-19 16:29:09 +01:00
parent fe63154f89
commit ae97da7b56
2 changed files with 15 additions and 95 deletions
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6
libraries/mbed/targets/hal/TARGET_STM/TARGET_NUCLEO_L152RE/sleep.c
View File

@ -102,17 +102,11 @@ static void SetSysClock_HSI(void)
// MCU SLEEP mode
void sleep(void)
{
// Disable us_ticker update interrupt
TIM_ITConfig(TIM9, TIM_IT_Update, DISABLE);
// Enable PWR clock
RCC_APB1PeriphClockCmd(RCC_APB1Periph_PWR, ENABLE);
// Request to enter SLEEP mode with regulator ON
PWR_EnterSleepMode(PWR_Regulator_ON, PWR_SLEEPEntry_WFI);
// Re-enable us_ticker update interrupt
TIM_ITConfig(TIM9, TIM_IT_Update, ENABLE);
}
// MCU STOP mode (Regulator in LP mode, LSI, HSI and HSE OFF)

104
libraries/mbed/targets/hal/TARGET_STM/TARGET_NUCLEO_L152RE/us_ticker.c
View File

@ -29,51 +29,12 @@
#include "us_ticker_api.h"
#include "PeripheralNames.h"
// Timer selection:
#define TIM_MST TIM9
#define TIM_MST_IRQ TIM9_IRQn
#define TIM_MST_RCC RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM9, ENABLE)
// 32-bit timer selection
#define TIM_MST TIM5
#define TIM_MST_IRQ TIM5_IRQn
#define TIM_MST_RCC RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM5, ENABLE)
static int us_ticker_inited = 0;
static volatile uint32_t SlaveCounter = 0;
static volatile uint32_t oc_int_part = 0;
static volatile uint16_t oc_rem_part = 0;
void set_compare(uint16_t count) {
// Set new output compare value
TIM_SetCompare1(TIM_MST, count);
// Enable IT
TIM_ITConfig(TIM_MST, TIM_IT_CC1, ENABLE);
}
static void tim_update_oc_irq_handler(void) {
uint16_t cval = TIM_MST->CNT;
// Update interrupt: increment the slave counter
if (TIM_GetITStatus(TIM_MST, TIM_IT_Update) == SET) {
TIM_ClearITPendingBit(TIM_MST, TIM_IT_Update);
SlaveCounter++;
}
// Output compare interrupt: used by interrupt system
if (TIM_GetITStatus(TIM_MST, TIM_IT_CC1) == SET) {
TIM_ClearITPendingBit(TIM_MST, TIM_IT_CC1);
if (oc_rem_part > 0) {
set_compare(oc_rem_part); // Finish the remaining time left
oc_rem_part = 0;
}
else {
if (oc_int_part > 0) {
set_compare(0xFFFF);
oc_rem_part = cval; // To finish the counter loop the next time
oc_int_part--;
}
else {
us_ticker_irq_handler();
}
}
}
}
static int us_ticker_inited = 0;
void us_ticker_init(void) {
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
@ -81,22 +42,18 @@ void us_ticker_init(void) {
if (us_ticker_inited) return;
us_ticker_inited = 1;
// Enable Timer clock
// Enable timer clock
TIM_MST_RCC;
// Configure time base
TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
TIM_TimeBaseStructure.TIM_Period = 0xFFFF;
TIM_TimeBaseStructure.TIM_Period = 0xFFFFFFFF;
TIM_TimeBaseStructure.TIM_Prescaler = (uint16_t)(SystemCoreClock / 1000000) - 1; // 1 µs tick
TIM_TimeBaseStructure.TIM_ClockDivision = 0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM_MST, &TIM_TimeBaseStructure);
// Configure interrupts
TIM_ITConfig(TIM_MST, TIM_IT_Update, ENABLE);
// For 32-bit counter and output compare
NVIC_SetVector(TIM_MST_IRQ, (uint32_t)tim_update_oc_irq_handler);
NVIC_SetVector(TIM_MST_IRQ, (uint32_t)us_ticker_irq_handler);
NVIC_EnableIRQ(TIM_MST_IRQ);
// Enable timer
@ -104,44 +61,15 @@ void us_ticker_init(void) {
}
uint32_t us_ticker_read() {
uint32_t counter, counter2;
if (!us_ticker_inited) us_ticker_init();
// A situation might appear when Master overflows right after Slave is read and before the
// new (overflowed) value of Master is read. Which would make the code below consider the
// previous (incorrect) value of Slave and the new value of Master, which would return a
// value in the past. Avoid this by computing consecutive values of the timer until they
// are properly ordered.
counter = (uint32_t)(SlaveCounter << 16);
counter += TIM_MST->CNT;
while (1) {
counter2 = (uint32_t)(SlaveCounter << 16);
counter2 += TIM_MST->CNT;
if (counter2 > counter) {
break;
}
counter = counter2;
}
return counter2;
return TIM_MST->CNT;
}
void us_ticker_set_interrupt(unsigned int timestamp) {
int delta = (int)(timestamp - us_ticker_read());
uint16_t cval = TIM_MST->CNT;
if (delta <= 0) { // This event was in the past
us_ticker_irq_handler();
}
else {
oc_int_part = (uint32_t)(delta >> 16);
oc_rem_part = (uint16_t)(delta & 0xFFFF);
if (oc_rem_part <= (0xFFFF - cval)) {
set_compare(cval + oc_rem_part);
oc_rem_part = 0;
} else {
set_compare(0xFFFF);
oc_rem_part = oc_rem_part - (0xFFFF - cval);
}
}
// Set new output compare value
TIM_SetCompare1(TIM_MST, timestamp);
// Enable IT
TIM_ITConfig(TIM_MST, TIM_IT_CC1, ENABLE);
}
void us_ticker_disable_interrupt(void) {
@ -149,7 +77,5 @@ void us_ticker_disable_interrupt(void) {
}
void us_ticker_clear_interrupt(void) {
if (TIM_GetITStatus(TIM_MST, TIM_IT_CC1) == SET) {
TIM_ClearITPendingBit(TIM_MST, TIM_IT_CC1);
}
TIM_ClearITPendingBit(TIM_MST, TIM_IT_CC1);
}