Update README.md

README.md

@@ -15,6 +15,8 @@ Locapack is distributed under the GPLv3 license. Please refer to the `LICENSE` f
 
 ## Packet structure details
 
+Message endianness is little endian.
+
 ### Packet general structure
 
 |    2B    |         2B        |    0/5B     |    1B (opt)   |  variable   |      1B       |            variable           |
@@ -36,7 +38,7 @@ The `localisation_packet_payload` length depends on the `localisation_packet_typ
 
 ### Header structure
 
-|         4b         |        4b        |            4b              |             1b              |           1b              |    2b    |
+| MSB     4b         |        4b        |            4b              |             1b              |           1b              |  2b LSB  |
 |--------------------|------------------|----------------------------|-----------------------------|---------------------------|----------|
 | `protocol_version` | `device_id_size` | `localisation_packet_type` | `movement_id_presence_flag` | `timestamp_presence_flag` | reserved |