iGNUiCould
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Works for me... Here's some code that uses it to get the readings from a DHT11 sensor. /* * temphumid.c: * Read Temperature / Humidity from DHT11 sensor * -iGNUiCould */ #include <wiringPi.h> #include <stdio.h> #define MAX_TIMINGS 85 #define DHTPIN 7 // GPIO pin for DHT11 data int data[5] = {0, 0, 0, 0, 0}; // Function to read data from DHT11 void readDHT11() { uint8_t lastState = HIGH; uint8_t counter = 0; uint8_t j = 0, i; data[0] = data[1] = data[2] = data[3] = data[4] = 0; // Send start signal to DHT11 pinMode(DHTPIN, OUTPUT); digitalWrite(DHTPIN, LOW); delay(18); digitalWrite(DHTPIN, HIGH); delayMicroseconds(40); pinMode(DHTPIN, INPUT); // Read data from DHT11 for (i = 0; i < MAX_TIMINGS; i++) { counter = 0; while (digitalRead(DHTPIN) == lastState) { counter++; delayMicroseconds(1); if (counter == 255) { break; } } lastState = digitalRead(DHTPIN); if (counter == 255) { break; } // Ignore first 3 transitions if ((i >= 4) && (i % 2 == 0)) { data[j / 8] <<= 1; if (counter > 16) { data[j / 8] |= 1; } j++; } } // Verify checksum and print data if valid if ((j >= 40) && (data[4] == ((data[0] + data[1] + data[2] + data[3]) & 0xFF))) { float humidity = data[0] + data[1] / 10.0; float tempC = data[2] + data[3] / 10.0; float tempF = tempC * 9.0 / 5.0 + 32; printf("Temperature = %.1f°F\n", tempF); printf("Humidity = %.1f%%\n", humidity); } else { printf("Data not valid\n"); } } int main() { if (wiringPiSetup() == -1) { printf("WiringPi setup failed\n"); return -1; } while (1) { readDHT11(); delay(2000); // Wait 2 seconds before reading again } return 0; }
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If this is still an issue for anyone, I forked into a repo that is modified to work exclusively with the M4 Zero. Confirmed working on the M4 Zero 4G / 32G model. Should work on other M4 Zero variants as long as the pins are the same. https://github.com/ignuicould/WiringBPi-M4Zero I also have pascal bindings for fpc / Lazarus if anyone is interested.
