MAX44009 I2C address problem

I am trying to use MAX44009 Ambient light sensor with CYW920819 board, but the I2C address options on MAX44009’s element library are only 0x4A or 0x4B.

According to this sensor’s datasheet, I2C addresses are 1001 010x, which is 0x94 or 0x95, if I am guessing correct. I tried to put the address here in the code

ATMO_Status_t MAX440091_setup(ATMO_Value_t *in, ATMO_Value_t *out) {
if(!MAX44009_Init(ATMO_PROPERTY(MAX440091, i2cInstance), ATMO_PROPERTY(MAX440091, i2cAddress)))
    return ATMO_Status_Fail;

return ATMO_Status_Success;


 but compiler throws error, how can I change I2C here ?


1001010x refers to the 8-bit address, where x is the read/write bit. In Atmosphere IoT, we only refer to the 7-bit address, which would be 0x4A. (1001010).

Please refer here for more info on I2C addressing.


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Ok, now it makes sense. Thank you !