Display RPM using an IR proximity sensor

Community Help With My Project
1

Hi
I have a program that calculates the rpm of a motor using an IR proximity sensor. This works pretty well, the rpm is correctly displayed in the serial monitor. But if I want to send this variable to Cayenne, it doesn’t show up correctly in the dashboard (it just says 0). Anyone with some advice? This is the code I used:

float rev = 0;
float rpm = 0;
unsigned long timeold = 0;
int measuretime = 1000;

void setup()
{
Serial.begin(115200);

attachInterrupt(digitalPinToInterrupt(5),RPMcount,FALLING);

Cayenne.begin(username, password, clientID, ssid, wifiPassword);

}

ICACHE_RAM_ATTR void RPMcount()
rev++;
}
void loop() {

Cayenne.loop();

if (millis() - timeold == measuretime)
{ detachInterrupt(digitalPinToInterrupt(5));
rpm=rev*(60000/measuretime);
Serial.println(rpm, DEC);
rev=0;
timeold=millis();
attachInterrupt(digitalPinToInterrupt(5),RPMcount,FALLING);
}

Cayenne.virtualWrite(1, rpm, “analog_sensor”, “null”);

2

do not place publish code in the main loop. Sending MQTT messages within rate limits

change to:

 void loop() {

if (millis() - timeold == measuretime)
{ 
Cayenne.loop();
detachInterrupt(digitalPinToInterrupt(5));
rpm=rev*(60000/measuretime);
Serial.println(rpm, DEC);
rev=0;
timeold=millis();
attachInterrupt(digitalPinToInterrupt(5),RPMcount,FALLING);
}

i am not sure whether this will work, but give it a try.

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