Toho Electronics TTX-800, Руководство по эксплуатации

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3.3 Explanation of MODBUS RTU Communication
3.3.1 Structure of MODBUS RTU Request Message (Data Transmission from the Upper Computer to This Product)
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See “ 3.3.3 Explanation of MODBUS RTU Codes ” for codes a) to g).
3.3.1.1 Structure of Read Request Message
a) Slave Address 01H
b) Function Code 03H
c) Register Address
Upper 00H
First register address
Lower 00H
d) Number of Registers
Upper 00H 2 (fixed)
※
Except for communication monitor
register address
Lower 02H
e) CRC-16
Lower C4H
Upper 0BH
3.3.1.2 Structure of Write Request Message
a) Slave Address 01H
b) Function Code 10H
c) Register Address
Upper 01H
First register address
Lower 00H
d) Number of Registers
Upper 00H
2 (fixed)
Lower 02H
f) Number of Bytes 04H Number of Registers x 2
g)
Data for the First Register
(Lower Word) Upper 00H ③
Data structure is ①②③④H.
(① represents 1 byte)
Lower 00H ④
Data for the First Register
(Upper Word)
Upper 00H ①
Lower 00H
②
e) CRC-16
Lower FEH
Upper 3FH
3.3.1.3 Structure of Save Request Message
a) Slave Address 01H
b) Function Code 10H
c) Register Address
Upper 09H
First register address
Lower 0CH
d) Number of Registers
Upper 00H
2 (fixed)
Lower 02H
f) Number of Bytes 04H Number of Registers x 2
g)
Data for the First Register
(Lower Word) Upper 00H
Data for saving the setting is
optional.
Lower 00H
Data for the First Register
(Upper Word)
Upper 00H
Lower 00H
e) CRC-16
Lower E8H
Upper E2H