Differences

This shows you the differences between two versions of the page.

--- communication:habpack [2018/04/29 21:32] – m0dny
+++ communication:habpack [2018/05/08 12:07] (current) – m0dny
@@ Line 1: / Line 1: @@
 ====== Habpack Binary Protocol ======
-This page details the msgpack based binary protocol. Habpack uses msgpack to encode the binary data, and defines how msgpack is used to encode telemetry, and defines IDs for telemetry fields
+This page details the [[https://msgpack.org/|msgpack]] based binary protocol. Habpack uses msgpack to encode the binary data, and defines how msgpack is used to encode telemetry, and defines IDs for telemetry fields.
+Encoders should pick the smallest type within the correct family. eg. '112' can be encoded as an unsigned int using the 'positive fixnum' type, for an encoded size of 1 byte. Unsigned integers are always assumed to be positive.
+This means that using integers can scale the storage required to the value being transmitted, while floats maintain a constant size (5 bytes for 32b float). See the msgpack spec for more details: [[https://github.com/msgpack/msgpack/blob/master/spec.md#type-system|msgpack spec -> type system]]
 ===== Basic Structure =====
@@ Line 16: / Line 20: @@
 ===== Telemetry field IDs =====
-This lists the IDs that habpack uses. There are reserved IDs to send data which is not already in the list of fields
-  * 0: callsign (as a string, or an integer ID)
-  * 1: count
-  * 2: time (as a string, or integer seconds past midnight UTC)
-  * 3: position (use a 3 element array: [lat, long, alt]. 1e-7 of a degree; meters)
-  * 4: satellites
-  * 5: lock type
-  * 10: internal temperature
-  * 11: external temperature
-  * 40: battery voltage (mV)
-  * 50: total uplinked messages
-As msgpack handles datatypes, arrays can be used to send multiple entries for one field. For example, if there are two external temperature sensors, this can be sent as 11:[-40.5,-39,1]
-===== Phil's Spec Proposal (March 2018) =====
-Encoders should pick the smallest type within the correct family. eg. '112' can be encoded as an unsigned int using the 'positive fixnum' type, for an encoded size of 1 byte. Unsigned integers are always assumed to be positive.
-This means that using integers can scale the storage required to the value being transmitted, while floats maintain a constant size (5 bytes for 32b float). See the msgpack spec for more details: [[https://github.com/msgpack/msgpack/blob/master/spec.md#type-system|msgpack spec -> type system]]
 A list of reserved Map IDs is suggested below to standardise parsing of commonly used telemetry fields without requirement of a payload-doc, eg. for embedded & offline receivers. This list is intended to be expanded over time as new requirements develop.
@@ Line 71: / Line 54: @@
   * 62: Multi-position array of positions (each: 2 or 3 element array of signed integers: [lat, long, <alt>]. 1e-7 degree; meters)
-,10,11,12,13,14,20 can be an array of legal values to represent more than one field.
+As msgpack handles datatypes, arrays can be used to send multiple entries for one field. For example, if there are two external temperature sensors, this can be sent as 11:[-40.5,-39,1] Types 6,10,11,12,13,14 can be an array of legal values to represent more than one field.
 ==== Current RPi Decoder Implementation ====
@@ Line 78: / Line 62: @@
 eg. "$$<callsign>,<count>,<time>,<lat>,<lon>,<alt>,<satellites>,<temp 1>,<temp 2>,<battery voltage>*<crc>"
-Multi-position:
-These fields will be binary-encoded as base64 and the resulting string appended as a single extra RTTY field.
 ==== LoRa Calling Beacon Modes (Field 21) ====