coines_read_stream_sensor_data

Reads the data streamed from the sensor.

int16_t coines_read_stream_sensor_data(uint8_t sensor_id, uint32_t number_of_samples, uint8_t *data, uint32_t *valid_samples_count);

Arguments:

• sensor_id: id of the sensor.
• number_of_samples: number of samples the user wishes to read (not implemented).
• data: data buffer.
  • Interrupt streaming - Packet counter + Register data + Timestamp
  • Polling streaming - Register data.
• valid_samples_count: number of samples the user has actually received (may be less than number_of_samples).

Example of a packet:

Fig. 13: Format of streaming packages

In the above figure, the following meaning apply to the mentioned abreviations:

• r_p: Value at register address p.
• a: Size of register block–0.
• r_p+a: Value at register address p.

Similarly is the case for r_q, j and r_q+j. See the coines_streaming_blocks structure for information regarding register blocks.

The packet counter and the timestamp can be obtained as follows:

packet_counter = (byte3_c << 24) | (byte2_c << 16) | (byte1_c << 8) | (byte0_c);
timestamp = (byte5_t << 40) | (byte4_t << 32) | (byte3_t << 24) | (byte2_t << 16) | (byte1_t << 8) | (byte0_t);

The 48-bit timestamp is enabled by using coines_trigger_timer(COINES_TIMER_START, COINES_TIMESTAMP_ENABLE);

Timestamp in microseconds can be obtained using below formula:

\[ Timestamp\ (\mu s) = \frac{48bit\_timestamp}{30}\]