Does anyone know of a way to handle sensor errors? I've added a picture of the serial monitor. Those erroneous readings going from 41.00 down to 2 are not actually occuring. It should just read 41.00. Temperature changes are gradual and slow for the thing I am measuring. I have the sensor connected using I2C and I am using the Adafruit_BMP085 library. I am just using bmp.readTemperature() to get the temperature from the sensor, and then simple mean averaging 30 readings - nothing special. One thing to note is that this had worked for some time, many months. Its just lately the readings are very erroneous as you can see. I wantes to introduce some code or some I2C error handling to ensure sensor readings are accurate. [20220618_191544]

SOLVED - I had 12V going to the Arduino, and too much on the Arduino +5V rail. Resulting in the Arduino overheating, producing the funky results I was seeing. Separate 5V regulator, with more current rating required. Thanks all for any help given.

Ive realised that I dont have pullup resistors on the SCL & SDA lines. Could this be my issue do people think?

If you're using modules as distinct from raw chips, don't the modules have pullups on them? If so, I think there's a chance that if they both have resistors, and you now have 2 sets in parallel, the resulting value is unsuitable. [image] DrDaveyG: I wrote the code about a year ago, and I am just starting to get problems now. So just to confirm, a year ago it was ok?

[image] void getTemperature(){ currentTemp = bmp.readTemperature(); total = total - readings[readNum]; readings[readNum] = currentTemp; total = total + readings[readNum]; readNum = readNum + 1; if (readNum >= numReadings) { readNum = 0; } averageTemp = total / numReadings; currentTempAverage = averageTemp; //Serial.print("AverageTemp:"); //DEBUGGING. //Serial.println(currentTempAverage); //DEBUGGING. }

Ive just disabled the temperature sensor, and just the rtc is doing weird stuff. I think the battery may just be dead or a bad module. I will replace and get back...

I see some garbage on the line. My guess is that its resetting and the average is restarting with all zeros, hence the low & increasing numbers.

Yeah definately. I think the rtc module might be hogging, or draghing down the scl sda lines, causing the bmp180 to loose connection and report 0 back or an error (not sure).

That is a good point! I will check the module boards to see if they have their own resistors. Edit: And yes, a year ago it worked fine.

Both modules have pullup resistors. I will remove them from the ds3231.

I do not think this has anything to do with the I2C. I am seeing the same issue on serial write: [image] void loop() { //getTemperature(); //tempSwitch(); DateTime now = rtc.now(); setInputFlags(); resolveInputFlags(); setCathodePoisonFlag(); if (cathodePoisonFlag == HIGH){ cathodePoisonPrevention(); cathodePoisonFlag = LOW; } else{ writeHours(now.hour()); writeMinutes(now.minute()); Serial.print("Hour: "); Serial.print(now.hour()); Serial.print(" "); Serial.print("Minutes: "); Serial.println(now.minute()); } } Oh yeah, its a Nixie clock. Cathode Poison occurs every 30mins and looks like this: [image] The common fault that occurs after this error, is that the Arduino Nano freezes. The serial monitor freezes, the clock freezes etc. I am wondering if something is locking up. I have replaced the Arduino Nano.

SOLVED - BMP180 Temperature Errors

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DrDaveyG June 20, 2022, 8:10pm 25

Apologies, I have edited it. I had to re-read the 'how to get the best out of the forum' post to remind myself of this. I have not posted code for a long while and forgot.

I will link it for others who may stumble across here, or me for future reference...

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SOLVED - BMP180 Temperature Errors

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