test the gpiote_example for timer0 in pca10003, the function is ok, LED blinking 200ms. but I change the timer0 to timer1 or timer2, the LED always on,and never blinking. what is the problem? the source code is atteched!
#include <stdbool.h>
#include <stdint.h>
#include "nrf.h"
#include "nrf_gpiote.h"
#include "nrf_gpio.h"
#include "boards.h"
#define GPIO_OUTPUT_PIN_NUMBER LED_0 /**< Pin number for PWM output. */
#define GPIOTE_CHANNEL_NUMBER 0 /**< GPIOTE channel number. */
/** @brief Function for initializing the GPIO Tasks and Events peripheral.
*/
static void gpiote_init(void)
{
// Configure GPIO_OUTPUT_PIN_NUMBER as an output.
nrf_gpio_cfg_output(GPIO_OUTPUT_PIN_NUMBER);
// Configure GPIOTE_CHANNEL_NUMBER to toggle the GPIO pin state with input.
// @note Only one GPIOTE task can be coupled to an output pin.
nrf_gpiote_task_config(GPIOTE_CHANNEL_NUMBER, GPIO_OUTPUT_PIN_NUMBER, \
NRF_GPIOTE_POLARITY_TOGGLE, NRF_GPIOTE_INITIAL_VALUE_LOW);
}
/** @brief Function for initializing Programmable Peripheral Interconnect (PPI) peripheral.
* The PPI is needed to convert the timer event into a task.
*/
static void ppi_init(void)
{
// Configure PPI channel 0 to toggle GPIO_OUTPUT_PIN on every TIMER0 COMPARE[0] match (200 ms)
NRF_PPI->CH[0].EEP = (uint32_t)&NRF_TIMER2->EVENTS_COMPARE[0];
NRF_PPI->CH[0].TEP = (uint32_t)&NRF_GPIOTE->TASKS_OUT[GPIOTE_CHANNEL_NUMBER];
// Enable PPI channel 0
NRF_PPI->CHEN = (PPI_CHEN_CH0_Enabled << PPI_CHEN_CH0_Pos);
}
/** @brief Function for initializing the Timer 0 peripheral.
*/
static void timer2_init(void)
{
// Start 16 MHz crystal oscillator.
NRF_CLOCK->EVENTS_HFCLKSTARTED = 0;
NRF_CLOCK->TASKS_HFCLKSTART = 1;
// Wait for the external oscillator to start.
while (NRF_CLOCK->EVENTS_HFCLKSTARTED == 0)
{
// Do nothing.
}
// Clear TIMER0
// NRF_TIMER2->POWER = TIMER_POWER_POWER_Enabled;
NRF_TIMER2->TASKS_CLEAR = 1;
// Configure TIMER0 for compare[0] event every 200 ms.
NRF_TIMER2->PRESCALER = 4; // Prescaler 4 results in 1 tick equals 1 microsecond.
NRF_TIMER2->CC[0] = 200*1000UL; // 1 tick equals 1µ , multiply by 1000 for ms value.
NRF_TIMER2->MODE = TIMER_MODE_MODE_Timer;
NRF_TIMER2->BITMODE = TIMER_BITMODE_BITMODE_24Bit;
NRF_TIMER2->SHORTS = (TIMER_SHORTS_COMPARE0_CLEAR_Enabled << TIMER_SHORTS_COMPARE0_CLEAR_Pos);
}
/**
* @brief Function for application main entry.
*/
int main(void)
{
gpiote_init(); // Configure a GPIO to toggle on a GPIOTE task.
timer2_init(); // Use TIMER0 to generate events every 200 ms.
ppi_init(); // Use a PPI channel to connect the event to the task automatically.
NRF_TIMER2->TASKS_START = 1; // Start event generation.
while (true)
{
// Do Nothing - GPIO can be toggled without software intervention.
}
}
