Protocol
A 12 byte message containing only an ID, commodity type, tamper flags and the current consumption value.
| Field | Length (bits) | Description |
|---|---|---|
| Preamble | 21 | 0x1F2A60 |
| Meter ID MSB | 2 | Two most significant bits of the ID. |
| Reserved | 1 | |
| Physical Tamper Flags | 2 | |
| Commodity Type | 4 | Indicates the commodity type of the meter. See list of meters: meters.md |
| Encoder Tamper Flags | 2 | |
| Consumption | 24 | The current consumption value. |
| Meter ID LSB | 24 | 24 least significant bits of the ID. |
| Checksum | 16 | A BCH code with generator polynomial: 
|
A 92 byte message containing differential consumption intervals.
| Field | Length (bytes) | Value | Description |
|---|---|---|---|
| Preamble | 2 | 0x5555 | |
| Sync Word | 2 | 0x16A3 | |
| Packet Type | 1 | 0x1C | |
| Packet Length | 1 | 0x5C | |
| Hamming Code | 1 | 0xC6 | Hamming code of first byte. |
| Application Version | 1 | ||
| Commodity Type | 1 | Least significant nibble is equivalent to SCM's commodity type field. | |
| Meter ID | 4 | Equivalent to SCM's Meter ID field. | |
| Consumption Interval Count | 1 | ||
| Module Programming State | 1 | ||
| Tamper Count | 6 | ||
| Async Count | 2 | ||
| Power Outage Flags | 6 | ||
| Last Consumption | 4 | Equivalent to SCM's consumption field. | |
| Differential Consumption | 53 | 47 intervals of 9-bit integers. | |
| Transmit Time Offset | 2 | 1/16ths of a second since the first transmission for this interval. | |
| Meter ID Checksum | 2 | CRC-16-CCITT of Meter ID. | |
| Packet Checksum | 2 | CRC-16-CCITT of packet starting at Packet Type. |
A 116 bit message containing ID, consumption, backflow and leak details.
| Field | Length (Bits) | Value | Description |
|---|---|---|---|
| Preamble | 32 | 0x0000E564 | |
| ID | 32 | ||
| Unkn1 | 8 | ||
| NoUse | 6 | Day bins of no use. See issue #29 for more details. | |
| BackFlow | 6 | Backflow in past 35 days, high/low. | |
| Consumption | 24 | ||
| Unkn3 | 2 | ||
| Leak | 4 | Day bins of leak. See issue #29 for more details. | |
| LeakNow | 2 | Leak in past 24 hours, high/low. |