//Boolean function to test if device responds
uint8_t test_connection(void){
    spi3_transmit_byte(0x0F); //Address of WHO_AM_I
    uint8_t who_am_i = spi3_receive_byte();
    return who_am_i == 0xD3; //0xD3 = default value of WHO_AM_I
}
//X-axis angular rate data. The value is expressed as two’s complement.
int16_t get_x_velocity(void){
    spi3_transmit_byte(0x28); //address of OUT_X_L
    uint8_t x_low = spi3_receive_byte();
    spi3_transmit_byte(0x29); //address of OUT_X_H
    uint8_t x_high = spi3_receive_byte();
    return (((uint16_t)x_high) << 8) & ((uint16_t)x_low);
}
//Y-axis angular rate data. The value is expressed as two’s complement.
int16_t get_y_velocity(void){
    spi3_transmit_byte(0x2A); //address of OUT_Y_L
    uint8_t y_low = spi3_receive_byte();
    spi3_transmit_byte(0x2B); //address of OUT_Y_H
    uint8_t y_high = spi3_receive_byte();
    return (((uint16_t)y_high) << 8) & ((uint16_t)y_low);
}
//Z-axis angular rate data. The value is expressed as two’s complement.
int16_t get_z_velocity(void){
    spi3_transmit_byte(0x2C); //address of OUT_Z_L
    uint8_t z_low = spi3_receive_byte();
    spi3_transmit_byte(0x2D); //address of OUT_Z_H
    uint8_t z_high = spi3_receive_byte();
    return (((uint16_t)z_high) << 8) & ((uint16_t)z_low);
}
//no idea if temperature is signed or not. or what the unit is.
int8_t get_temperature(void){
    spi_transmit_byte(0x26); //address of OUT_TEMP
    return spi3_receive_byte();
}