11: Modbus
XPort Pro User Guide
100
Serial Transmission Mode
Evolution products can be set up to communicate on standard Modbus networks using either RTU
or ASCII. Users select the desired mode and serial port communication parameters (baud rate,
parity mode, etc) during the line configuration.
Table 11-4
Modbus Transmission Modes
The Modbus web pages allow you to check Modbus status and make configuration changes. This
chapter contains the following sections:
Modbus Statistics
Modbus Configuration
Force
Multiple
Coil
0x0F
Echo query
Echo query
Echo query
Echo
query
N/A
N/A
N/A
Preset
Multiple
Registers
0x10
Echo query
Echo query
Echo query
Echo
query
N/A
N/A
N/A
Read/
Write 4X
Registers
0x17
0x02-0x06
(Quantity of
Read) * 2
Max [6]..
0x00, 0x0Y
0x00 ,0x0Y
0x00, 0x0Y
Y = 0 or 1
RTU
ASCII
Address: 8 bits (0 to 247 decimal, 0 is used
for broadcast)
Function: 8 bits (1 to 255, 0 is not valid)
Data: N X 8 bits (N=0 to 252 bytes)
CRC Check: 16 bits
Address: 2 CHARS
Function: 2 CHARS
Data: N CHARS (N=0 to 252 CHARS)
LRC Check: 2 CHARS
Name
Number
Byte
Count
Data [0]
Data [1]
Data
[2]
Data [3]
Data
[4]
Data [5]
