CCS/CC2640R2F: SensorI2C with custom board

Part Number:CC2640R2F

Tool/software: Code Composer Studio

Hi,

I would like to interface the BQ32002DR (RTC) with CC2640R2F. I try to use the SensorI2C.h. 

I write:

SensorI2C_open();
SensorI2C_select(0, 0xD0);

the SensorI2C_select is ok, if I modify the code with:

if(SensorI2C_select(1, 0xD0)){

System_printf("true\n");
System_flush();

} else {

System_printf("false\n");
System_flush();

}

I get true on console.

but the instructions: 

SensorI2C_writeReg or SensorI2C_readReg return false.

Can I modify the instructions in SensorI2C.h to adapt them my purposes?

Are there other function that allow a good and easy interfacing or have I to do them?

Thanks.

Best regards.

Giuseppe