LS Industrial Systems GLOFA G7M-DR20U, Руководство пользователя

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Chapter 8. Communication Functions
8-6
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Control code
- The control codes used are as follow. Be familiar with the following control codes, because they are important for communication.
Codes Hex value Name Contents
ENQ H05 Enquire
Request frame initial code
ACK H06 Acknowledge
ACK response frame initial code
NAK H15 Not Acknowledge NAK response frame initial code
EOT H04 End of Text
Request frame ending ASCII code
ETX H03 End Text
Response frame ending ASCII code
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The numerical data of all frames are ASCII codes equal to hexadecimal value, if there’s no clear statement.
The terms in hexadecimal are as follows.
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Station No.
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When the main command is R(r) or W (w) and the command type is numerical (means a data type)
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All of the terms indicating size of all data in the formatted data area.
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Monitoring registration and command registration number of execution commands.
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All contents of data
If it is hexadecimal, H is attached in front of the number of frames like H01, H12345, H34, H12, and H89AB
1) Sequence of command frame
(1) Sequence of command request frame
REMARK
(PLC NAK response)
(PLC ACK response)
Station
no.
Command Data or Null ETX BCC ACK
Station no. Command Formatted data EOT BCC ENQ
Station
no.
Command Data or Null ETX BCC NAK