// Code segment 3.1

#include <stdio.h>

#include "freertos/FreeRTOS.h"

#include "freertos/task.h"

#include "driver/gpio.h"


// Function declaration

int readPinState(int pin);


// Button and LED pin definitions

#define BUTTON_PIN 4

#define LED_PIN 2


void app_main() {

// Configure button pin as input

gpio_set_direction(BUTTON_PIN, GPIO_MODE_INPUT);


// Configure LED pin as output

gpio_set_direction(LED_PIN, GPIO_MODE_OUTPUT);


while (1) {

// read the button pin

int btnVal = readPinState(BUTTON_PIN);


// display the button state.

// Not pressed while state = 1, Pressed while state = 0

if (btnVal == 1) { // not pressed

vTaskDelay(pdMS_TO_TICKS(200));

printf("Button not pressed. ");

printf("Button state = %d\n", btnVal);

gpio_set_level(LED_PIN, 0); // Turn off LED

}


else { // pressed

vTaskDelay(pdMS_TO_TICKS(200));

printf("Button pressed. ");

printf("Button state = %d\n", btnVal);

gpio_set_level(LED_PIN, 1); // Turn on LED

}

}

}


/* Function Name - readPinState

* Description - read the state of a pin

* Return type - integer

* Parameters - pin - a GPIO pin

*/

int readPinState(int pin) {

return gpio_get_level(pin);

}