output formatted data

main.go

@@ -9,14 +9,13 @@ import (
 )
 
 const Timeout = math.MaxInt32
-const TimeoutErrInitial string = "Timed out waiting for sensor's initial %s reading!"
+const TimeoutErrInitial string = "timed out waiting for sensor's initial %s reading"
 
 var oneSecondInCycles = (func() int {
 	result := cyclesInAMillisecond()
 	for i := 0; i < 100; i++ {
 		result += cyclesInAMillisecond()
 	}
-	fmt.Println(result / 100)
 	return result / 100
 })()
 
@@ -41,65 +40,39 @@ func main() {
 
 	pinNumber := gpio.GPIO4
 	pin := gpio.NewPin(pinNumber)
-	result, err := readDataFromDHT(pin)
+	dhtData, err := readDataFromDHT(pin)
 	if err != nil {
-		fmt.Println(fmt.Sprintf("Bad read! Reason: %s", err.Error()))
+		fmt.Println(fmt.Sprintf("Bad read! Reason: %s!", err.Error()))
 	} else {
-		fmt.Println(result)
+		fmt.Println(convertToRhAndTemp(dhtData))
 	}
 }
 
 func readDataFromDHT(pin *gpio.Pin) ([5]byte, error) {
-	receivedInput := [5]byte{0, 0, 0, 0, 0}
 	// Setup
 	pin.PullUp()
 	time.Sleep(time.Second)
-
 	// Send start signal
 	pin.Low()
 	pin.Output()
 	time.Sleep(1100 * time.Microsecond)
 	pin.Input()
 	time.Sleep(40 * time.Microsecond)
-
-	// Get Data
+	// Wait for high low signal
 	if cyclesForReading(pin, gpio.Low) == Timeout {
-		return receivedInput, errors.New(fmt.Sprintf(TimeoutErrInitial, "low"))
+		return [5]byte{}, errors.New(fmt.Sprintf(TimeoutErrInitial, "low"))
 	}
 	if cyclesForReading(pin, gpio.High) == Timeout {
-		return receivedInput, errors.New(fmt.Sprintf(TimeoutErrInitial, "high"))
+		return [5]byte{}, errors.New(fmt.Sprintf(TimeoutErrInitial, "high"))
 	}
-
-	// Store cycle number for each low and high pulse
-	cycles := [80]int{}
-	for i := 0; i < 80; i += 2 {
-		cycles[i] = cyclesForReading(pin, gpio.Low)
-		cycles[i + 1] = cyclesForReading(pin, gpio.High)
-	}
-
-	err := storeCycleCountsAsBinarySequence(&receivedInput, &cycles)
+	pulsesAsCycles := readPulsesAsCycles(pin)
+	receivedInput, err := storeCycleCountsAsBinarySequence(&pulsesAsCycles)
 	if err != nil {
-		return receivedInput, err
+		return [5]byte{}, err
 	}
-
 	return receivedInput, nil
 }
 
-func storeCycleCountsAsBinarySequence(store *[5]byte, cycles *[80]int) error {
-	for i := 0; i < 40; i++ {
-		lowCycles := cycles[2 * i]
-		highCycles := cycles[2 * i + 1]
-		if (lowCycles == Timeout) || (highCycles == Timeout) {
-			return errors.New("Timed out waiting for sensor pulse!")
-		}
-		store[i / 8] <<= 1
-		if highCycles > lowCycles {
-			store[i / 8] |= 1
-		}
-	}
-	return nil
-}
-
 func cyclesForReading(pin *gpio.Pin, level gpio.Level) int {
 	count := 0
 	for pin.Read() == level {
@@ -110,3 +83,35 @@ func cyclesForReading(pin *gpio.Pin, level gpio.Level) int {
 	}
 	return count
 }
+
+func readPulsesAsCycles(pin *gpio.Pin) [80]int {
+	cycles := [80]int{}
+	for i := 0; i < 80; i += 2 {
+		cycles[i] = cyclesForReading(pin, gpio.Low)
+		cycles[i + 1] = cyclesForReading(pin, gpio.High)
+	}
+	return cycles
+}
+
+func storeCycleCountsAsBinarySequence(cycles *[80]int) ([5]byte, error) {
+	data := [5]byte{}
+	for i := 0; i < 40; i++ {
+		lowCycles := cycles[2 * i]
+		highCycles := cycles[2 * i + 1]
+		if (lowCycles == Timeout) || (highCycles == Timeout) {
+			return [5]byte{}, errors.New("timed out waiting for sensor pulse")
+		}
+		data[i / 8] <<= 1
+		if highCycles > lowCycles {
+			data[i / 8] |= 1
+		}
+	}
+	return data, nil
+}
+
+func convertToRhAndTemp(data [5]byte) (float32, float32) {
+	rh := float32(data[0]) + float32(int(data[1]) << 4)
+	temp := float32(data[2]) + float32(int(data[3]) << 4)
+	return rh/10, temp/10
+}
+