#include <stdlib.h>

#include <stdio.h>

#include <signal.h>

#include <string.h>

#include <unistd.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <sys/ioctl.h>

#include <sys/select.h>

#include <fcntl.h>

#include <math.h>

#include <util/util.h>

#include <errno.h>

#define SYSFS_ADC_DIR "/sys/bus/iio/devices/iio:device0/in_voltage0_raw"

#define SYSFS_ADC_DIR2 "/sys/bus/iio/devices/iio:device0/in_voltage6_raw"

#define MAX_BUFF 64

//check that the character is numeric

int caracter_valido(const char cad)

{

return cad >= '0' && cad <='9';

}

// converts an string into a integer

int mi_atoi(const char *cad, int tam)

{

int i=tam-1, entero=0, pos=1;

while (i>=0)

{

while (caracter_valido(cad[i])){

entero=entero+(cad[i]-48)*pos;

pos=pos*10;

i--;

}

pos=1;

i--;

}

return entero;

}

int main(void) {

int value;

int fd;

int value2;

int fd2;

char buf[MAX_BUFF];

char ch[5]; //Update

char ch2[5]; //Update

ch[4] = 0; //Update

int GPIOPin=60, /* GPIO1_28 or pin 12 on the P9 header */

printf("\nStarting GPIO output program\n");

FILE *myOutputHandle = NULL;

char setValue[4], GPIOString[4], GPIOValue[64], GPIODirection[64];

sprintf(GPIOString, "%d", GPIOPin);

sprintf(GPIOValue, "/sys/class/gpio/gpio%d/value", GPIOPin);

sprintf(GPIODirection, "/sys/class/gpio/gpio%d/direction", GPIOPin);

// Export the pin

if ((myOutputHandle = fopen("/sys/class/gpio/export", "ab")) == NULL){

printf("Unable to export GPIO pin\n");

return 1;

}

strcpy(setValue, GPIOString);

fwrite(&setValue, sizeof(char), 2, myOutputHandle);

fclose(myOutputHandle);

// Set direction of the pin to an output

if ((myOutputHandle = fopen(GPIODirection, "rb+")) == NULL){

printf("Unable to open direction handle\n");

return 1;

}

strcpy(setValue,"out");

fwrite(&setValue, sizeof(char), 3, myOutputHandle);

fclose(myOutputHandle);

// export pin 2

GPIOPin=50;

sprintf(GPIOString, "%d", GPIOPin);

sprintf(GPIOValue, "/sys/class/gpio/gpio%d/value", GPIOPin);

sprintf(GPIODirection, "/sys/class/gpio/gpio%d/direction", GPIOPin);

// Export the pin

if ((myOutputHandle = fopen("/sys/class/gpio/export", "ab")) == NULL){

printf("Unable to export GPIO pin\n");

return 1;

}

strcpy(setValue, GPIOString);

fwrite(&setValue, sizeof(char), 2, myOutputHandle);

fclose(myOutputHandle);

// Set direction of the pin to an output

if ((myOutputHandle = fopen(GPIODirection, "rb+")) == NULL){

printf("Unable to open direction handle\n");

return 1;

}

strcpy(setValue,"out");

fwrite(&setValue, sizeof(char), 3, myOutputHandle);

fclose(myOutputHandle);

while(1) {

//read adc ch0

snprintf(buf, sizeof(buf), SYSFS_ADC_DIR);

fd = open(buf, O_RDONLY);

read(fd,ch,4);

close(fd);

value= mi_atoi(ch, strlen(ch));

value= (value*100)/2667;

sleep(0.1);

//read adc ch 6

snprintf(buf, sizeof(buf), SYSFS_ADC_DIR2);

fd2 = open(buf, O_RDONLY);

read(fd2,ch2,4);

close(fd2);

value2= mi_atoi(ch2, strlen(ch));

// if the solar power is high and the current from the motor is low, then shut down the fuel cell and turn the solar charger on, otherwise the fuel cell is always on.

if (value > 80 && value2 < 1000){

GPIOPin=60;

sprintf(GPIOString, "%d", GPIOPin);

sprintf(GPIOValue, "/sys/class/gpio/gpio%d/value", GPIOPin);

sprintf(GPIODirection, "/sys/class/gpio/gpio%d/direction", GPIOPin);

if ((myOutputHandle = fopen("/sys/class/gpio/export", "ab")) == NULL){

printf("Unable to export GPIO pin\n");

return 1;

}

strcpy(setValue, GPIOString);

fwrite(&setValue, sizeof(char), 2, myOutputHandle);

fclose(myOutputHandle);

// Set output to low

if ((myOutputHandle = fopen(GPIOValue, "rb+")) == NULL){

printf("Unable to open value handle\n");

return 1;

}

strcpy(setValue, "0"); // Set value low

fwrite(&setValue, sizeof(char), 1, myOutputHandle);

fclose(myOutputHandle);

sleep(0.5); // wait for 1 sec

GPIOPin=50;

sprintf(GPIOString, "%d", GPIOPin);

sprintf(GPIOValue, "/sys/class/gpio/gpio%d/value", GPIOPin);

sprintf(GPIODirection, "/sys/class/gpio/gpio%d/direction", GPIOPin);

if ((myOutputHandle = fopen("/sys/class/gpio/export", "ab")) == NULL){

printf("Unable to export GPIO pin\n");

return 1;

}

strcpy(setValue, GPIOString);

fwrite(&setValue, sizeof(char), 2, myOutputHandle);

fclose(myOutputHandle);

// Set output to high

if ((myOutputHandle = fopen(GPIOValue, "rb+")) == NULL){

printf("Unable to open value handle\n");

return 1;

}

strcpy(setValue, "1"); // Set value high

fwrite(&setValue, sizeof(char), 1, myOutputHandle);

fclose(myOutputHandle);

sleep(0.5); // wait for 1 sec

}else{

GPIOPin=50;

sprintf(GPIOString, "%d", GPIOPin);

sprintf(GPIOValue, "/sys/class/gpio/gpio%d/value", GPIOPin);

sprintf(GPIODirection, "/sys/class/gpio/gpio%d/direction", GPIOPin);

if ((myOutputHandle = fopen("/sys/class/gpio/export", "ab")) == NULL){

printf("Unable to export GPIO pin\n");

return 1;

}

strcpy(setValue, GPIOString);

fwrite(&setValue, sizeof(char), 2, myOutputHandle);

fclose(myOutputHandle);

// Set output to low

if ((myOutputHandle = fopen(GPIOValue, "rb+")) == NULL){

printf("Unable to open value handle\n");

return 1;

}

strcpy(setValue, "0"); // Set value low

fwrite(&setValue, sizeof(char), 1, myOutputHandle);

fclose(myOutputHandle);

sleep(0.5); // wait for 1 sec

GPIOPin=60;

sprintf(GPIOString, "%d", GPIOPin);

sprintf(GPIOValue, "/sys/class/gpio/gpio%d/value", GPIOPin);

sprintf(GPIODirection, "/sys/class/gpio/gpio%d/direction", GPIOPin);

if ((myOutputHandle = fopen("/sys/class/gpio/export", "ab")) == NULL){

printf("Unable to export GPIO pin\n");

return 1;

}

strcpy(setValue, GPIOString);

fwrite(&setValue, sizeof(char), 2, myOutputHandle);

fclose(myOutputHandle);

// Set output to high

if ((myOutputHandle = fopen(GPIOValue, "rb+")) == NULL){

printf("Unable to open value handle\n");

return 1;

}

strcpy(setValue, "1"); // Set value high

fwrite(&setValue, sizeof(char), 1, myOutputHandle);

fclose(myOutputHandle);

sleep(0.5); // wait for 1 sec

}

printf("potencia solar: %d \n",value);

printf("corriente del motor %d \n",value2);

}

return 0;

}