This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ21061: Cannot write to the device

Part Number: BQ21061

I am trying to configure the BQ21061 and when I try to write to a register the I2C frames are acknowledged correctly (the I2C transfer is successful) but when I read back the register I just wrote to, the data I read back is the default reset data and the data that I wrote.

The scope trace below shows me trying to write a 0x05 to the VBAT_CTRL register.  I immediately read back the register and read the default value of 0x3c and not the 0x05 that I wrote.

The blue trace is I2C_CLK, the red trace is I2C_Data, the yellow trace is LP and the green trace is CE.  Both LP and CE are high.

MR is not connected.

Do you have any idea what I may be doing wrong?