BME280.py script not pulling set point/current temp


#1

Puzzled here as the bme280.py script renders this in paper UI:

Traceback (most recent call last): File “/home/pi/scripts/bme280.py”, line 173, in main() File “/home/pi/scripts/bme280.py”, line 161, in main (chip_id, chip_version) = readBME280ID() File “/home/pi/scripts/bme280.py”, line 56, in readBME280ID (chip_id, chip_version) = bus.read_i2c_block_data(addr, REG_ID, 2) IOError: [Errno 121] Remote I/O error Traceback (most recent call last): File “/home/pi/scripts/bme280.py”, line 173, in main() File

Obviously it is looking for a device address of the ds18b20 sensor I am using for temp reading. The temp sensor will read back with cat w1 slave, i2c tools are installed/enabled in RPI, smbus, etc. I can run a python script which also will feed back a temp reading no problem.
i2cdetect -y 1 and 0 outputs no address. Do I need an address to plug in the bme280 script in order to pull temp readings for hestia and openhab? Should another script be used in place of bme280?


#2

the ds18b20 and the bme280 use different configurations / pin / hardware setups so what works for one will poss not work for another. First off I would use a dmm (multi meter on continuity test) and test the cable that is attached to the bme280. I am no expert but I had an error the same or close to yours and it turned out to be a broken wire to the sensor. I made the cable a tad too short and it got caught in the case as I pushed the front cover on. (the cable looked ok from just looking at it, it was only when testing the cable it showed faulty.

Sirhc


#3

The temp sensor works via raspberry and with python script on raspberry. Not that.


#4

See the FAQ page
https://hestiapi.com/faq/
(section “Use DHT sensors instead of the default BME”)
The default software and hardware configuration is for BME sensor so if you want to use DHT follow these changes and should be fine.


#5

Hestiapi is set up to use the bme280 by default, you need to change the config as per staff message if you want to change the default to use a dht22. If you want to use a ds18b20 instead then you will have to write/code up your own config and setup. the 3 devices I have just mentioned are all completely different in the way they need to be used.

I think the ds18b20 is more used as a remote temp sensor as an addon to hestiapi rather than the main unit temp sensor.

(maybe I miss read the problem) but because your say you are getting an error related to the bme then that means the setup is looking for the bme280 sensor chip and not finding it attached to the system

Sirhc


#6

Sorry, I read your post wrong so I was referring to the DHT sensors. DS18B20 are not supported. This can easily be done with another script if you want to play with scripting but we don’t really like DS18B20 as it is very inaccurate and produces sporadic readings. DHT and BME are much better and the price difference (0 for DHT and 2 € for the BME) is insignificant to its importance in your home thermostat.

That’s right.


#7

Perfect, thanks for the info.