uint8 user_i2c_write_byte(bitserial_handle handle, uint8 reg, uint8 value);
uint8 user_i2c_write_buffer(bitserial_handle handle, uint8 buffer[], uint16 buflen);
uint8 user_i2c_read(bitserial_handle handle, uint8 txdat,uint8 rxbuf[], uint8 rxlen);