sensor on i2c with 0x76 address doesn't work since update
LukaGitH opened this issue · 17 comments
It stopped working with 2.0, works fine in 1.2
Hi Luka - Thank you for checking my work! Please have a look at the latest commit. I've updated example 2 (I was trying to do too much in one example). I've tested on both RedBoard and Teensy and should be good to go.
I've also added an advanced example 9 that uses software I2C. It's a bit of a hack job, and requires the user to edit the SparkFunBME280.h file but I'd welcome your feedback.
Additionally, I've added a basic SPI example.
Once you give me the green light I'll push a release so the library manager will increment.
The problem is still here, sensor witn 0x76 can't be read. Even the old I2C_and_SPI_Multisensor which for mySensorB changed to:
mySensorB.settings.commInterface = I2C_MODE;
mySensorB.settings.I2CAddress = 0x76;
Is not working, while in 1.2 version it works fine. Therefor I think the problem is library still
Program Started
Starting BME280s... result of .begin():
Sensor A: 0x60
Sensor B: 0x58
Temperature: 21.91, 0.00 degrees C
Temperature: 71.44, 32.00 degrees F
Pressure: 95971.60, 0.00 Pa
Altitude: 470.81, 45846.20m
Altitude: 1544.65, 150414.04ft
What platform are you compiling on? What platform are you compiling for?
In Arduino IDE, for pro mini
It works fine for me. Pro Mini, 3.3V @ 8MHz. I am using the BME280 on our Combo board.
What board are you using? If you're using our BME280 breakout did you close the jumper on the back of the board?
Interesting. I'm using Pro Mini, 5V @ 16MHz running from 3.3v (yes out of specs according to 328p datasheet , but everything works, several dozen different sensors, oleds, RF transceivers...)
In fact, I use two of this kind. One is BME280, other is BMP280
In any case, with older library it worked, with new is doesn't read 0x76 correctly. What is interesting is that 0x77 works as expected while other address does not. This then can't be timing issue. It must be somewhere, when address is switched and wrong registers are read.
Neat! Ok, have you pulled the SDO pin to ground, before powering the device, to set the address to 0x76?
Yes, SDO is always ground on one, while Vcc on other. Like I said, hardware didn't change, only software did.
Hmm. This delay was delay(10) in the original library. Please try changing that from 2 to 10 and see if it fixes your problem?
I think I have worked it out. It is not delay, since there was no delay before. Delay can stay at 2ms.
What the problem is, is this:
BME can be 0x76 or 0x77
BMP can be only 0x77
BME has ID 0x60, BMP has ID 0x58 (mass production, samples have different ID)
in CPP, you check for
if(chipID != 0x60) return(chipID); //Failed!
Which fails in case of BMP, so to fix this, this needs to be changed to
if(chipID != 0x60) // This is not BME
if(chipID != 0x58) // This is not BMP
return(chipID); //Failed!
So does
if(begin() == 0x60) return(true); //Begin normal init with these settings. Should return chip ID of 0x60
return(false);
to
if(begin() == 0x58) return(true); //Begin normal init with these settings. Should return chip ID of 0x58
if(begin() == 0x60) return(true); //Begin normal init with these settings. Should return chip ID of 0x60
return(false);
AH! That's really cool. Your board must have some of the original, samples?, ICs.
Do you feel like writing a PR that implements your recommendations?
No, my BMP are mass production, 0x58
From datasheet, BME doesn't samples.
Sure! It's my first time, hope I get it right
Ah, now I understand. This library is written for the BME280, you're using the BMP280. If you want to submit a PR to allow the library to work with both BME and BMP I'm happy to have a look. I'm closing this because this is not really an issue with the library.
HW-611difficult to figure out which sense is this.
I think this is a fake BMP280.
What do you think 🤔
Can this read humidity?
@sonybansi Can you clarify what sensor you think is fake? Also, this library is for the BME280 instead of the BMP...
HW-611difficult to figure out which sense is this.
I think this is a fake BMP280.
What do you think 🤔
Can this read humidity?
Oh, the picture wasn't showing up for me for some reason. I am not sure which sensor you have, read the chipid as described above to determind which sensor you have.