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Re: Attempting to read BME280 sensor from WiPy 2.0 but having trouble ...
Posted: Sun Oct 28, 2018 5:03 pm
by pythoncoder
On a Pyboard, with nothing connected to the I2C bus, scan() returns instantly with []. I think you have some kind of hardware problem. To prove the point, disconnect your hardware and run scan() again.
Re: Attempting to read BME280 sensor from WiPy 2.0 but having trouble ...
Posted: Sun Oct 28, 2018 5:15 pm
by sealyons
Yep, returns immediately if I disconnect everything. Any idea what type of hardware issue this might be?
Re: Attempting to read BME280 sensor from WiPy 2.0 but having trouble ...
Posted: Sun Oct 28, 2018 5:18 pm
by Roberthh
So maybe the pull-up resistors on SDA and SCL are missing. You can try to add 4.7 kOhm between SDL and Vcc and SDA and Vcc.
Re: Attempting to read BME280 sensor from WiPy 2.0 but having trouble ...
Posted: Sun Oct 28, 2018 5:29 pm
by pythoncoder
It is going to be hard for us to debug this remotely: either your hardware is broken or it is wired incorrectly. I'd put a multimeter on the data and clock lines: both should read 3.3V in the idle state. My guess is that one or both is being pulled low.
Re: Attempting to read BME280 sensor from WiPy 2.0 but having trouble ...
Posted: Sun Oct 28, 2018 5:36 pm
by sealyons
With 4 lines, it's hard to imagine it's wired incorrectly. I can try to add pull-ups. I'll also check the voltage levels on SDA & SCL. However I'm late for an appt. so I'm done for the day. I really appreciate your help. I'll be back tomorrow.