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Interrupt and Overflow check for us_ticker

pull/4840/head
Ganesh Ramachandran 2017-08-09 19:11:36 +05:30 committed by Ganesh Ramachandran
parent 0a781c4f04
commit 9dca3fe5df
1 changed files with 23 additions and 11 deletions
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34
targets/TARGET_TOSHIBA/TARGET_TMPM066/us_ticker.c
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@ -14,24 +14,24 @@
* limitations under the License.
*/
#include "us_ticker_api.h"
#include "mbed_critical.h"
#define TMR16A_100US 0x960 // fsys = fc = 24MHz, Ttmra = 1/24us, 100us*24us = 2400 = 0x960
#define TMR16A_SYSCK ((uint32_t)0x00000001)
#define TMR16A_RUN ((uint32_t)0x00000001)
#define TMR16A_STOP ((uint32_t)0x00000000)
#define OVERFLOW_32BIT (0xFFFFFFFF / 0x64)
static uint8_t us_ticker_inited = 0; // Is ticker initialized yet?
static volatile uint32_t acc_us_ticker = 0;
// 16Bb high timer counter
static volatile uint32_t us_ticker_16h = 0;
static uint8_t us_ticker_inited = 0; // Is ticker initialized yet?
static volatile uint32_t ticker_int_counter = 0; // Amount of overflows until user interrupt
static volatile uint32_t us_ticker = 0; // timer counter
void INT16A0_IRQHandler(void)
{
us_ticker_16h++;
if (us_ticker_16h >= 0xFFFF) {
acc_us_ticker++;
us_ticker_16h = 0;
us_ticker++;
if (us_ticker > OVERFLOW_32BIT) {
us_ticker = 0;
}
}
@ -67,18 +67,30 @@ uint32_t us_ticker_read(void)
if (!us_ticker_inited) {
us_ticker_init();
}
ret_val = (((acc_us_ticker << 16) + us_ticker_16h) * 100);
uint32_t tickerbefore = 0;
do {
tickerbefore = us_ticker;
ret_val = (us_ticker * 100);
} while (tickerbefore != us_ticker);
return ret_val;
}
void us_ticker_set_interrupt(timestamp_t timestamp)
{
int delta = 0;
// Stops and clear count operation
TSB_T16A1->RUN = TMR16A_STOP;
TSB_T16A1->CR = TMR16A_SYSCK;
// Set the compare register
delta = (int)(timestamp - us_ticker_read());
if (delta < 0) {
// Ticker interrupt handle
us_ticker_irq_handler();
return;
}
TSB_T16A1->RG = delta;
// Set Interrupt
NVIC_EnableIRQ(INT16A1_IRQn);
@ -98,5 +110,5 @@ void us_ticker_disable_interrupt(void)
void us_ticker_clear_interrupt(void)
{
//no flags to clear
NVIC_ClearPendingIRQ(INT16A1_IRQn);
}