esp-idf/examples/peripherals/sigmadelta/main/sigmadelta_example_main.c
Angus Gratton 821c70f5d7 examples: Standardise naming of files, symbols, etc. in examples
* Use "example" in all example function & variable names,
  ie use i2c_example_xxx instead of i2c_xxx for example functions.
  Closes #198 https://github.com/espressif/esp-idf/issues/198
* Mark example functions, etc. static
* Replace uses of "test" & "demo" with "example"
* Split the UART example into two
* Rename "main" example files to end with "_main.c" for disambiguation
2017-03-27 17:42:05 +11:00

55 lines
1.5 KiB
C

/* Sigma-delta Example
This example code is in the Public Domain (or CC0 licensed, at your option.)
Unless required by applicable law or agreed to in writing, this
software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
CONDITIONS OF ANY KIND, either express or implied.
*/
#include <stdio.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_system.h"
#include "driver/sigmadelta.h"
/*
* This test code intended to configure sigma-delta and set GPIO4 as signal output pin.
* If you connect this GPIO4 with an LED, you will see the LED blinking slowly.
*/
/**
* @brief Sigma-delta initialization.
*/
static void sigmadelta_example_init(void)
{
sigmadelta_config_t sigmadelta_cfg = {
/* Sigma-delta channel0*/
.channel = SIGMADELTA_CHANNEL_0,
/* Sigma-delta set duty 10*/
.sigmadelta_duty = 10,
/* Set prescale 30 */
.sigmadelta_prescale = 80,
/*select GPIO4 as output_io */
.sigmadelta_gpio = 4,
};
sigmadelta_config(&sigmadelta_cfg);
}
/**
* @brief Sigma-delta test to change duty of output signal.
*/
void app_main()
{
sigmadelta_example_init();
int8_t duty = 0;
int inc = 1;
while(1) {
sigmadelta_set_duty(SIGMADELTA_CHANNEL_0, duty);
/*by changing delay time, you can change the blink frequency of LED. */
vTaskDelay(10 / portTICK_PERIOD_MS);
duty += inc;
if(duty == 127 || duty == -127) inc = (-1) * inc;
}
}