I am working on a project that sends data using 125 kHz signal. So far, I have used LEDC to generate 125kHz signal ok and can switch it on and off using the timer_pause and timer_resume. However, I cannot turn it on an off fast enough without getting watchdog timer errors showing up.
I need to be able to switch the time on and off for bit times of 280us.
My code is below...
Code: Select all
#include <stdio.h>
#include "driver/ledc.h"
#include "freertos/freeRTOS.h"
#include "freertos/task.h"
#define PWM_CH0_GPIO (18)
void PWM_Init(void)
{
ledc_timer_config_t ledc_timer = {
.speed_mode = LEDC_HIGH_SPEED_MODE,
.duty_resolution = LEDC_TIMER_8_BIT,
.timer_num = LEDC_TIMER_0,
.freq_hz = 125000,
.clk_cfg = LEDC_AUTO_CLK
};
ledc_timer_config(&ledc_timer);
ledc_channel_config_t ledc_channel = {
.gpio_num = PWM_CH0_GPIO,
.speed_mode = LEDC_HIGH_SPEED_MODE,
.channel = LEDC_CHANNEL_0,
.intr_type = LEDC_INTR_DISABLE,
.timer_sel = LEDC_TIMER_0,
.duty = 127
};
ledc_channel_config(&ledc_channel);
}
void app_main(void)
{
printf("Init PWM\n");
PWM_Init();
for(;;)
{
ledc_timer_pause(LEDC_HIGH_SPEED_MODE,LEDC_TIMER_0);
vTaskDelay(50/portTICK_PERIOD_MS);
ledc_timer_resume(LEDC_HIGH_SPEED_MODE,LEDC_TIMER_0);
vTaskDelay(50/portTICK_PERIOD_MS);
}
}