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ATIM_1GATE_INDUS2_UG_EN_V1.2
MODBUS server
When MODBUS integration is chosen, devices uplink messages are stored in MODBUS registers. The gateway behaves
as MODBUS TCP server (slave) and registers can be read from external MODBUS master.
All data is encoded in hexadecimal.
50 registers (100 bytes) are allocated per device and can be divided into three parts:
- 4 registers are allocated to
device EUI
- 4 registers are allocated to
timestamp
- 42 registers are allocated to message data
payload
EXEMPLE
For example, the tab below indicates:
Device EUI
70b3d59ba000a761
Timestamp
1416020f090739
Data payload
10cea0cea64
For each part, data is stacked on the right, which implies that lot of registers are set to zero, particularly if payload is short.
When a new device is registered and join Chirpstack LoRaWAN server, it will be added to the list automatically.
For example, if three devices have been registered on LoRaWAN network server first, then registers below will be set:
- Registers [0 - 49] allocated to device 1
- Registers [50 - 99] allocated to device 2
- Registers [100 - 149] allocated to device 3
If a device sends various type of message (for example life frames and data frames) no difference can be made,
frames are stored in the same registers, which means that earlier frame will erase older one.
