I would like to try the BME280 after one of my DHT22 humidity is stuck at 100%. I am confuse which one of the 2 below I need.
From my experience upper one is BME280, while lower one is BMP280 (this one doesn’t have humidity). Also you can see from price: more expensive one is BME280.
From what you have said, I am more confused. From my amazon site, the 6 pins (1st image) is cheaper then the 4pins (2nd image).
Also, I have found this how to and it shows he is using the 4 pins and his config has temp, humidity, and pressure.
All mine are 4 pin as shown
Strange… well, in this case only thing i can remember is that depends where you buy them. As i said: all my BME’s have 6 pins, while BMP’s have 4. Also on aliexpress that is the common practice when you do the search.
I ordered 4-pin BME’s once on aliexpress and i’ve got BMP’s. When i complained the seller wanted to convince me that i ordered BMP’s. Luckily on my order page it was clearly stated that i ordered BME’s. So, at the end we settled for 50% refund.
So, be very carefull. First of all, if they are dirty cheap, then they are probably BMP’s.
I disagree. I have around 6 of them all less than $5AUD and purchased off ebay.com.au. All have been BME’s with Temp/Pressure and Humidity
Interesting… i didn’t find them cheaper than just over 1 USD per piece… like i said: when i did, it turned out that they were BMP’s…
BME280 and BMP280 both support I²C and SPI protocols. The PCB with the 4 pins expose the I²C interface, the 6 pin version exposes the SPI. Functionally they are equivalent, they’re just using a different interface to connect to the MCU.
Since both sensors support both protocols, there’s no direct relation between pin number and whether you get a BME or BMP. That’s up to the vendor and whether the product listing on Amazon or Ali lists the correct chip. These are generic PCBs, so you’ll find either sensor on either board.
Hello to all! I am new to home assistant and I started out with the same problem a lot of you are having with the bme280 sensor. I tried everything in here to no avail, then I soldered the sensor directly to the board and it works perfectly. I discovered that its nothing in the code at all but in the wiring. If you use cat 5e cable, not the kind with double foil shield or anything, and use a pair for +v and a pair for gnd, then take another pair for scl and ground, and the last pair for sda and ground this will work as intended. The problem is in the cabling and has to do with capacitance on the I2C bus. It creates noise and corrupts the data and can make it unpredictable or not work at all. I hope this helps anyone with this issue.
In the log, the temperature and humidity pressure values are normally displayed, but only the humidity values are visible on the dashboard screen. I don’t know what to do.
I am having the same problem. Stuff shows in the logs but not in HA
Sorry, no help
Grey
I was having this same issue with the 6-pin BME280 (I2C and SPI interface) and came across this link where they state the chip can revert to SPI for some reason. By pinning CSB to high (3v/5v) it forces it to stay on I2C. Since doing that, mine has been rock solid.
This discussions explains a bit more on the behavior
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For those like me that are slow, please talk a bit more about how to “pin CSB to high”. I would appreciate being educated.
Just wire the CSB pin to the same source voltage as the VCC pin 
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This shows a diagram and explains
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I had the feeling it was that, but, I have found that asking questions is never a dumb thing to do. Testing now.
I’ll be back.
Nope, but something else is wrong (I’m experimenting with ESPHome on Pico), I’ll report back if I fix the other thing.
@ciscojunkie Well. So that totally works. I’m amazed, and very happy.
In fact, I’d go so far as to say that, given how much crap people have with this sensor, this hack should be mentioned in the esphome.io docs.
… not that it’s strictly a hack or whatever. I’m just saying. I’ve had trouble with BM(P/E)280 for years, and this is the first time I’ve read about this. Maybe my googlefu just sucks.
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