webgpt.ninja

    Here is a sample C code to read temperature and humidity from 6 DHT22 sensors connected to GPIO ports 4, 5, 6, 23, 24, and 25, and write the data to separate CSV files named SensorX.csv:
            

            #include <stdio.h>
#include <wiringPi.h>
#include <dht.h>
#include <time.h>

#define DHT_PIN_4 4
#define DHT_PIN_5 5
#define DHT_PIN_6 6
#define DHT_PIN_23 23
#define DHT_PIN_24 24
#define DHT_PIN_25 25

#define MAX_SENSORS 6

void writeToCSV(int pin, float temperature, float humidity) {
    char filename[20];
    sprintf(filename, "Sensor%d.csv", pin);
    FILE *file = fopen(filename, "a");
    if (file != NULL) {
        time_t now = time(NULL);
        struct tm *t = localtime(&now);
        fprintf(file, "%d-%02d-%02d %02d:%02d:%02d,%.2f,%.2f\n", t->tm_year + 1900, t->tm_mon + 1, t->tm_mday, t->tm_hour, t->tm_min, t->tm_sec, temperature, humidity);
        fclose(file);
    } else {
        printf("Error opening file %s\n", filename);
    }
}

int main() {
    wiringPiSetup();
    
    int pins[MAX_SENSORS] = {DHT_PIN_4, DHT_PIN_5, DHT_PIN_6, DHT_PIN_23, DHT_PIN_24, DHT_PIN_25};
    float temperature, humidity;
    
    for (int i = 0; i < MAX_SENSORS; i++) {
        int dht22 = dhtInit(pins[i], DHT22);
        if (dht22 < 0) {
            printf("Failed to initialize DHT sensor on GPIO %d\n", pins[i]);
        } else {
            if (dhtRead(dht22, &temperature, &humidity) == DHT_SUCCESS) {
                writeToCSV(pins[i], temperature, humidity);
            } else {
                printf("Failed to read data from DHT sensor on GPIO %d\n", pins[i]);
            }
            delay(2000); // wait for 2 seconds before reading next sensor
        }
    }
    
    return 0;
}
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        Make sure to install the `wiringPi` library and `dht` library before compiling and running the code. You can compile the code using the following command:

```bash
gcc -o read_sensors read_sensors.c -lwiringPi -lpthread
```

This code will read temperature and humidity data from 6 DHT22 sensors connected to the specified GPIO pins and write the data to separate CSV files named SensorX.csv. Each CSV file will have a timestamp, temperature, and humidity data in a comma-separated format.

    Here is a simple C library for DHT22 sensor that you can use to read temperature and humidity data from the sensor:
            

            #include <wiringPi.h>
#include <stdint.h>
#include <stdio.h>

#define MAX_TIMINGS 85
#define DHT_PIN 4

int data[5] = {0, 0, 0, 0, 0};

int read_dht_data() {
    uint8_t laststate = HIGH;
    uint8_t counter = 0;
    uint8_t j = 0, i;
    data[0] = data[1] = data[2] = data[3] = data[4] = 0;
    
    pinMode(DHT_PIN, OUTPUT);
    digitalWrite(DHT_PIN, LOW);
    delay(18);
    digitalWrite(DHT_PIN, HIGH);
    delayMicroseconds(40);
    pinMode(DHT_PIN, INPUT);
    
    for (i = 0; i < MAX_TIMINGS; i++) {
        counter = 0;
        while (digitalRead(DHT_PIN) == laststate) {
            counter++;
            delayMicroseconds(1);
            if (counter == 255) {
                break;
            }
        }
        laststate = digitalRead(DHT_PIN);
        
        if (counter == 255) {
            break;
        }
        
        if ((i >= 4) && (i % 2 == 0)) {
            data[j / 8] <<= 1;
            if (counter > 16) {
                data[j / 8] |= 1;
            }
            j++;
        }
    }
    
    if ((j >= 40) && (data[4] == ((data[0] + data[1] + data[2] + data[3]) & 0xFF))) {
        return 1;
    } else {
        return 0;
    }
}

float get_temperature() {
    float temperature = (float)((data[2] & 0x7F) * 256 + data[3]) / 10.0;
    if (data[2] & 0x80) {
        temperature *= -1;
    }
    return temperature;
}

float get_humidity() {
    return (float)((data[0] * 256 + data[1]) / 10.0);
}
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        You can use this library to read data from the DHT22 sensor by calling `read_dht_data()` function to read the sensor data, and then use `get_temperature()` and `get_humidity()` functions to get the temperature and humidity values respectively. Make sure to include the necessary headers and wiringPi library before compiling and using this library.

Please note that this is a basic library and may need further modifications based on your specific requirements and use case.