Si7021 reading issue with NRF52832 breakout

Sensors Environmental
1

Hi, I am having a problem communicating Si7021 T/H sensor with the NRF52832 Breakout Board.

I’ve done step-by-step through the hook-up guide according to (https://learn.sparkfun.com/tutorials/nr … -guide/all) and (https://learn.sparkfun.com/tutorials/si … -guide/all) but the Serial Monitor appears no reading. When I disconnect the sensor, the Serial Monitor shows the following reading.

https://i.imgur.com/gRzjLY4.png

Once I connected the sensor back to the I2C line, the Serial Monitor freeze, stop showing data unless I disconnect the SDA line from the sensor.

I hooked up a logic analyzer and found out that the Master(NRF52832) performs correctly when not connected to the sensor,

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https://i.imgur.com/4bSPR7v.png

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https://i.imgur.com/WeypuRJ.png

When connected to the sensor, the logic always shows high.

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https://i.imgur.com/P8ui4dZ.png

I’ve changed the pinout for I2C in variant.h()

#define PIN_WIRE_SDA         (15)
#define PIN_WIRE_SCL         (14)

When I hook up my sensor to Arduino nano, everything work just fine.

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https://i.imgur.com/c3gNi78.png

I use the S132 soft device on the NRF52832.

I think there is something wrong with the sensor.begin or wire.begin function using on nrf52832 board but I can’t find the cause.

2

And I used another library, there is a problem with the ACK/NACK.

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https://i.imgur.com/TcPwBym.png

3

Hello, and thanks for your post.

We don’t know if our library for the Si7021 works with the nRF52832. The library was written for an Arduino board and it’s very possible that it won’t work on a Nordic board.

Sadly, we can’t help, but if you find a solution, please post it so that others can see.