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Table 7 Downlink Configuration Message 0x0B
Byte Description
0
Mode: 0x00 for Threshold, or 0x01 for Report on Change
1-6
Defined by Mode (See Mode sections)
The mode byte selects one of two modes: threshold based alerts or report-on-change alerts.
The remainder of the payload (bytes 1-6) are determined by the mode selected and defined
in the next two sections.
6.3.1.
Threshold Mode
Threshold mode is set when byte 0 of the payload is set to 0x00. The remainder of the
payload is defined in the following table.
Table 8 Downlink Configuration Message for Threshold Mode
Byte Description
0
0x00 (Threshold mode)
1
Periodic reporting minute or hour intervals. Default is 0 (disabled)
2
Restoral margin (bits 3:0 only).
3
Lower ambient light threshold.
4
Upper ambient light threshold.
The upper and lower ambient light thresholds are unsigned values and should fall on the
scale 0-255.
The Restoral Margin is used for the upper and lower thresholds and requires the
ambient light value to cross back over the threshold a certain amount before a new
event is reported. This prevents excessive event messages if the ambient light is at or
near the threshold.
For example, consider an upper light threshold set at 100 and the restoral margin set at
5. If the ambient light initially exceeds 100 then an event is generated and a message is
sent to the network. The ambient light must now drop to 95 and then exceed 100
before another event is reported.
