I connect one CortexM4 board with FXAS21002 on FRDM-STBC-AGM01 by I2C.
Slave address 0x20 is used because SA0=0 is pull-down.. When read register WHO_AM_I(0x0c)，0 is returned. Analyzed with oscilloscope, the I2C communication works well. 0 is sent from slave side.
When read register (INT_SOURCE_FLAG)0x0B, it is also 0.
Why? Do I need to configure additional parameters? How to make it works? Thanks very much.
Pseudo code : I2CMasterTransmit(SlaveAddress 0x20, RegisterAddress 0x0C)
Pin: MCU SCL <-> FRDM-STBC-AGM01 SCL
MCU SDA <-> FRDM-STBC-AGM01 SDA
MCU VDD <-> FRDM-STBC-AGM01 VDD
MCU GND <-> FRDM-STBC-AGM01 GND