Tempus

When the request contains a Tempus payload, the value Tempus will be in the deviceType field of the uplink request.

Tempus devices create RFID event records and transmit them periodically. Since records are placed in memory and scheduled for later transmission, the device timestamp is stored and transmitted as well.

All timestamps from Tempus are generated in UTC time and are encoded as an integer representing seconds since the date 2020 -01-01 00:00:00. Following is an example converting the transmitted device timestamps into DateTime structs in C#.

var time = 124671610;
var convertedTime = new DateTime(2020, 1, 1, 0, 0, 0, DateTimeKind.Utc).AddSeconds(time);

Tempus payloads contain one or more of the following fields.

{
  "payloadSync": 8,
  "timeSync": 3,
  "battery": 83,
  "time": 124671610,
  "records": [
    {
      "time": 124675036,
      "state": 0,
      "id": "551d3597"
    },
    {
      "time": 124675395,
      "state": 1,
      "id": "23de2084"
    }
  ]
}

Base payload

Field Name	Type	Conditional	Description	Notes
payloadSync	int	No	A payload sync word. This is used earlier in the communication chain and can be ignored for most purposes.	Possible values are 0 to 15
timeSync	int	No	A time sync word. This is used in the time synchronization protocol and can be ignored for most purposes.	Possible values are 0 to 15
battery	int	Yes	The current device battery level.	Possible values are 0 to 100
time	uint	Yes	The current device time.	Seconds since 2020-01-01T00:00:00Z
records	array	Yes	This field contains an array of record objects (see below). These are the actual events recorded by the Tempus device

Record objects

Field Name	Type	Conditional	Description	Notes
time	uint	No	The device time at which the event was recorded.	Seconds since 2020-01-01T00:00:00Z
state	int	No	The event that was recorded.	0 for check in, 1 for check out
id	string	No	The RFID tag id.	Length can vary depending on tag type.

Documentation still in preparation...

19 juni 2025