Fairford agility Series, User Manual, Page: 43 / 127

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agility TM Series Soft Start User Manual
MAN-AGY-001. Version 04. 21/09/2018
Write Multiple Registers
Description: writing register blocks of holding register type (block R/W limited to 8 registers).
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Function code: 16 example
Memory Map
agility TM Modbus communication is based on reading or writing equipment parameters from or to the
holding registers. The data addressing is zero offset, such that the parameter Modbus address corresponds
to the register number.
Modbus Address Memory Map
Parameter Modbus
Address
Modbus Data Address
Decimal Hex
0000 0 0000h
0001 1 0001h
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0128 128 0080h
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Message Timing
In the RTU mode there is no specific start or stop byte that marks the beginning or the end of a
message. Indication of when a new message begins or when it ends is achieved by the absence of
data transmission for a minimum period of 3.5 times the transmission time of a data byte. Thus, in case a
message is transmitted after this minimum time has elapsed; the network elements will assume that the
first received character represents the beginning of a new message.
Modbus Function 16 Transaction Table
Query Response
Field Hex Byte Field Hex Byte
Slave address 01 Slave address 01
Function 10 Function 10
Address Hi 00 Address Hi 00
Address Lo 01 Address Lo 01
# Words Hi 00 # Words Hi 00
# Words Lo 01 # Words Lo 01
# Bytes 02 CRC Lo 50
Data Hi 00
CRC Hi 09
Data Lo 02
CRC Lo 26
CRC Hi 40
Communication (continued)