User Manual

Table Of Contents
On Air Message Format 3-2
SmartPoint Module for the Elster A3 Meter ECMTM40000
3.1.5 Control
Provides status data to the receiver.
3.1.5.1 RF Sequence Number
A 4 bit modulo 16 counter, increments each RF transmission.
3.1.5.2 AC Power Fail
Set if AC Power is not present. In AC only powered end point devices, set in Last Gasp messages.
3.1.5.3 Battery Low
Tested under load, this bit is set if the input voltage is below a certain threshold. The bit is valid on
next transmitted message.
3.1.5.4 Power Restore
Set in the first new message after a power up, cleared otherwise.
3.1.5.5 Payload Encrypted
Set if the payload data has on-air encryption turned on, cleared otherwise.
3.1.6 Length
The number of remaining data bytes in the on air message not including the CRC bytes. Initially, there
will be 1 fixed value of length to facilitate receiver firmware functionality: 31 bytes.
Bits Control
0-3 RF Sequence Number
4 AC Power Failed
5 Power Restored
6 Low Battery Detected
7 Payload Encrypted