I am trying to establish a connection between the biometric hub and the MCU dev. board. I am successfully generating I2C data from the MCU and verified it using a scope logic analyzer. However, I do not receive any response from the biometric hub.
I have attached two external pull up resistors between the MCU and the biometric hub SDA and SCL lines (pull up resistors attached to 1.8V source). I have provided 3.3V to the biometric hub. I would like to know if anyone has experience establishing communication between these two devices and if so, can you please help me?
How do you know if the biometric hub dev board is on and ready to receive I2C data? Maybe I’m missing some configuration before trying to send I2C data?
First, you need to enter the application mode which is done using the RSTN and MFIO pins (see user guide). You can then check if the MAX32664 is in application mode by requesting the device operation mode registers content by transmitting the following bytes over the I2C bus:
After a required delay of 2ms (see user guide) you should request the data using the following sequence
TX: 0xAB (address: read)
RX: 0x00 (indicates a successful I2C transmission (see status byte)), 0x00 (MAX32664 in application operating mode)
Besides, if you configured the sensor according to the user guide then the red LED of the MAX30101 should shine if you place your finger for instance close to the sensor.