Hi,
the signal from the hub dynamo are converted by a trigger into a rectangle signal. Then I measure the period of the signal with the pulseIn() function at pin 25 of my ESP32 device.
int getFrequency() {
float freq = 0;
// use pulseIn function
// disable interrupt during measure
noInterrupts();
// measure HIGH and LOW
if ( debug == 1 ) {
Serial.println("DEBUG: call pulseIn functions on measurePin:" + String(measurePin) );
}
Htime = pulseIn(measurePin, HIGH, PULSE_TIMEOUT); //read high time
Ltime = pulseIn(measurePin, LOW, PULSE_TIMEOUT); //read low time
if ( debug == 1 ) {
Serial.println("DEBUG: after pulseIn functions" );
Serial.println("DEBUG: Htime: " + String(Htime) );
Serial.println("DEBUG: Ltime: " + String(Ltime) );
}
//enable interrupts again
interrupts();
Ttime = Htime + Ltime;
if ( Ttime > 0 ) {
if ( debug == 1 ) {
Serial.println("DEBUG: Ttime = " + String(Ttime) );
}
freq = 1000000 / Ttime; //getting frequency with Ttime is in micro seconds
}
// display frequency
if ( debug2 == 1 ) {
return (freq_fixed);
} else {
return (freq);
}
}
Then the distance will be calculated:
void getDistance() {
// speed in m/s wheel_size in mm
current_speed = ( frequency / dynamo_pulse ) * wheel_size / 1000.0 ;
// distance in m/s
distance_during_measurement = current_speed * _MEASURE_INTERVAL;
// calculate the current speed in km/h
current_speed *= 3.6;
// count the total distance in m of the current day
distance_daily += distance_during_measurement;
distance_daily_km = distance_daily / 1000.0 ;
// count the total distance in m
distance_total += distance_during_measurement;
distance_total_km = distance_total / 1000.0 ;
// convert distance_total_km into integer with round function
//distance_total_lora = round(distance_total_km);
if ( debug == 1 )
{
Serial.print("DEBUG: measurement_interval in seconds = ");
Serial.println(_MEASURE_INTERVAL);
Serial.print("DEBUG: current_speed in km/h = ");
Serial.println(current_speed);
Serial.print("DEBUG: distance_during_measurement in m = ");
Serial.println(distance_during_measurement);
Serial.print("DEBUG: distance_daily in m = ");
Serial.println(distance_daily);
Serial.print("DEBUG: distance_total in m = ");
Serial.println(distance_total);
Serial.print("DEBUG: distance_total_lora in km = ");
Serial.println(distance_total_lora);
Serial.println("");
}
}
But currently I have a problem, if I activate the LMIC functions in my code. With LMIC enabled the pulseIn() function returns always zero.
This is the main part with no activated LoRa functions.
void setup()
{
Serial.begin(115200); //INTIALISING THE SERIAL COMMUNICATION
pinMode(measurePin, INPUT);
// initialize OLED display
u8x8.begin();
initDisplay();
// initialize LoRa
//initLoRa();
}
void loop() {
uint32_t currentSeconds;
currentSeconds = (uint32_t) millis() / 1000;
if ( debug == 2 ) {
Serial.print("DEBUG: currentSeconds: ");
Serial.println(currentSeconds);
Serial.print("DEBUG: measuretime: ");
Serial.println(measuretime);
Serial.print("DEBUG: _MEASURE_INTERVAL: ");
Serial.println(_MEASURE_INTERVAL);
}
if ((currentSeconds - measuretime) >= _MEASURE_INTERVAL) { // Wake up every xx seconds
// get the dynamo frequency
frequency = getFrequency();
if ( debug == 1 ) {
Serial.print("DEBUG: Frequency: ");
Serial.println(frequency);
}
getDistance();
showDistance();
measuretime = currentSeconds;
}
//os_runloop_once();
}
Do you have any idea, why the pulseIn function returns always zero, if LMIC is active?
