User`s guide

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3. Verify Communication Settings
The Serial MODBUS supports 2 transmission modes: RTU and
ASCII. The default communication is MODBUS-RTU, 8 data bits, No
Parity, 1 Stop bit (8-N-1), 19200 baud. The MODBUS slave ID or
MODBUS address is 95 or 0x5F.
The following commands (Function Codes, denoted FC) are
supported:
FC = 1: Read Coils
FC = 5: Write Single Coil
FC = 15: Write Multiple Coils
FC = 3: Read Holding Registers
FC = 6: Write Single Register
FC = 16: Write Multiple Registers
All other commands, exceptions, or other interface features are not
supported.
Note:
Raw addressing starts at 0. For FC-specific addressing, the address
starts at 1 for coils and 40001 for holding registers. Denoted in the literature
as 0 / 1 or 1 / 40001.
4. Perform Communication Verifications
Poll the WACTIVE gateway coil @ 0 / 1 address. This should return
False if no sensors have been registered yet.
Poll the Gateway ID registers @ 1-2 / 40002-40003 addresses and
verify the number returned matches the Gateway ID on the bottom
of your serial MODBUS gateway (four or five digit number near the
bar code).
If the device times-out or gives some other error, please see the
Monnit Serial MODBUS Gateway User’s Manual for example
MODBUS communications.