BMI I2C: Shuttle board connections and write/read functions

[SaberKazemi1992]

Hi Bosch sesnrtec community

I am using BMI160 IMU (shuttle board) as motion sesnor in my application. The MCU is MSP432P401R.

1- What is the proper wiring configuration for the shuttle board for I2C protocol?

2- I have written the code for I2C read/write functions like below:

/************BMI160 I2C*********/
UCB1CTLW0 |= UCSWRST; // **Initialize USCI state machine**
P6SEL0 |= BIT4 + BIT5;
P6SEL1 &= ~(BIT4 + BIT5); // | P6.3: UCB1SCLK| P6.4: UCB1SIMO | P6.5: UCB1SOMI (Refer to the datasheet, page: 159).
UCB1CTLW0 |= UCCKPH + UCMST + UCMSB + UCSYNC + UCSSEL_2 + UCMODE_3; // 3-pin, 8-bit, SPI master
UCB1BR0 = 12; // fSCL = SMCLK/12 = ~250kHz
UCB1BR1 = 0;
UCB1I2CSA = BMI160_I2C_ADDR; // Set slave address
UCB1CTLW0 &= ~UCSWRST; // **Initialize USCI state machine**

int8_t user_i2c_read(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len)
{
int8_t rslt = 0; /* Return 0 for Success, non-zero for failure */

/*
* The parameter dev_id can be used as a variable to store the I2C address of the device
*/
UCB1CTLW0 |= UCTR + UCTXSTT; // I2C TX, start condition
UCB1TXBUF = reg_addr; // Write reg_addr byte
UCB1CTLW0 |= UCTXSTP; // I2C stop condition.

UCB1I2CSA |= BMI160_I2C_ADDR; // Set slave address
UCB1CTLW0 &=~UCA10; //10BIT ADDRESS
UCB1CTLW0 &=~UCTR;//CLEAR TRANSMIT MODE
UCB1CTLW0 |= UCTXSTT; // I2C RX, start condition
int i=0;
for (i=0;i<len;i++)
{
reg_data[i]=UCB1RXBUF;
}
UCB1CTLW0 |= UCTXSTP; // I2C stop condition.

return rslt;
}

int8_t user_i2c_write(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len)
{
int8_t rslt = 0; /* Return 0 for Success, non-zero for failure */
UCB1CTLW0 |= UCTR + UCTXSTT; // I2C TX, start condition
UCB1TXBUF = reg_addr; // Write reg_addr byte
int i=0;
for (i=0;i<len;i++)
{
UCB1TXBUF=reg_data[i];
}
UCB1CTLW0 |= UCTXSTP; // I2C stop condition.

return rslt;
}

 Is it the right statement for them?

Thanks

Saber

[SaberKazemi1992]

Thanks for your previous answers.

I have one more question with regard the pin connections. In the datasheet, page 100, it is mentioned that that GND should be connected to the VDDIO with 100 nF capacitor. As I am using the shuttle board, do I need to connect these two pins externally or they are already connected in the board?

Thanks

Saber 

[o_o]

no, the shuttle has its own decoupling.
o_o