1. CayenneLPP

What is CayenneLPP?

Provides a convenient and easy way to send data over LPWAN Networks such as LoRaWAN. The CayenneLPP is compliant with the payload size restriction, which can be lowered down to 11 bytes, and allows the device to send multiple sensor data at one time.

It implements basic sensor types specified by OMA SpecWorks, formerly IPSO Alliance. It supports multichannel data, which means that you can use it on multisensor devices.

How does it work?

CayenneLPP allows the device to send different sensor data in different frames. In order to do that, each sensor data must be prefixed with two bytes:

• Data Channel: Uniquely identifies each sensor in the device across frames, eg. “indoor sensor”
• Data Type: Identifies the data type in the frame, eg. “temperature”.

Payload structure

Byte	1 Byte	N Bytes	1 Byte	1 Byte	M Bytes	...
Data1 Ch.	Data1 Type	Data1	Data2 Ch.	Data2 Type	Data 2	...

Data Types

Data Types conform to the IPSO Alliance Smart Objects Guidelines, which identify each data type with an “Object ID”. However, as shown below, a conversion is made to fit the Object ID into a single byte.

LPP_DATA_TYPE = IPSO_OBJECT_ID - 3200

Each data type can use 1 or more bytes to send the data according to the following table.

Type	IPSO	LPP	Hex	Data Size	Data Resolution per bit
Digital Input	3200	0	0	1	1
Digital Output	3201	1	1	1	1
Analog Input	3202	2	2	2	0.01
Analog Output	3203	3	3	2	0.01
Illuminance Sensor	3301	101	65	2	1
Presence Sensor	3302	102	66	1	1
Temperature Sensor	3303	103	67	2	0.1°C Signed MSB
Humidity Sensor	3304	104	68	1	0.5 % Unsigned
Accelerometer	3313	113	71	6	0.001 G Signed MSB per axis
Barometer	3315	115	73	2	0.1 hPa Unsigned MSB
Gyrometer	3334	134	86	6	0.01 °/s Signed MSB per axis
GPS Location	3336	136	88	9	Latitude : 0.0001 ° Signed MSB
GPS Location	3336	136	88	9	Longitude : 0.0001 ° Signed MSB
GPS Location	3336	136	88	9	Altitude : 0.01 meter Signed MSB

Examples

Device with 2 temperature sensors

Payload (Hex)	03 67 01 10 05 67 00 FF
Data Channel	Type	Value
03 ⇒ 3	67 ⇒ Temperature	0110 = 272 ⇒ 27.2°C
05 ⇒ 5	67 ⇒ Temperature	00FF = 255 ⇒ 25.5°C

Device with temperature and acceleration sensors

Frame N

Payload (Hex)	01 67 FF D7
Data Channel	Type	Value
01 ⇒ 1	67 ⇒ Temperature	FFD7 = -41 ⇒ -4.1°C

Frame N + 1

Payload (Hex)	06 71 04 D2 FB 2E 00 00
Data Channel	Type	Value
06 ⇒ 6	71 ⇒ Accelerometer	X: 04D2 = +1234 => + 1.234G
06 ⇒ 6	71 ⇒ Accelerometer	Y: FB2E = -1234 => - 1.234G
06 ⇒ 6	71 ⇒ Accelerometer	Z: 0000 = 0 => 0G

Device with GPS

Payload (Hex)	01 88 06 76 5f f2 96 0a 00 03 e8
Data Channel	Type	Value
01 ⇒ 1	88 ⇒ GPS	Latitude: 06765f ⇒ 42.3519
01 ⇒ 1	88 ⇒ GPS	Longitude: F2960a ⇒ -87.9094
01 ⇒ 1	88 ⇒ GPS	Altitude: 0003E8 ⇒ 10 meters