Pulsar dBi-M, Инструкция по эксплуатации

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PULSAR MEASUREMENT
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CHAPTER 6 MODBUS
Modbus Protocol
The exchange of information between Master and Slave devices is done
using the Modbus RTU communication protocol (19200-8E1). This protocol
allows read and write operations over Registers allocated in the dBi-M unit.
The protocol includes (among others) an 8-bit field defined as Device
Address, a 8-bit field defined as Function Code, a 16-bit field defined as
Register Address, and 32-bit field(s) defined as Register(s).
Device Address
Each Modbus slave has a unique Modbus address. The Modbus protocol
defines the address range limits as 1 to 247. However, the dBi-M Series will
support an address range of 1 to 126. The device address used by the dBi-
M is set using the parameter shown below:
PAR. NO. OPTIONS DESCRIPTION
P133 1 to 126
Device Address – Enter the Modbus
device number for the dBi-M transducer.
Function Codes
Pulsar dBi-M Modbus Protocol supports functions 3, 4, 6 and 16. These
registers are listed below:
FUNCTION CODE FUNCTION DESCRIPTIONS PLC ADDRESS
03 Read holding registers 40XXX
04 Read Input registers 30XXX
06 Write to a single register 40XXX
16 Write to multiple registers 40XXX
Important Notice
Out of the box the dBi-M is set to the following Modbus Protocol:
Modbus ID = 126
Serial setup: 19200
– 8 – E - 1
Note: Only Slave operation with Modbus RTU is available.