LS Industrial Systems GLOFA G7M-DR20U, Руководство пользователя

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Chapter 8. Communication Functions
8-16
(3) GM7U main unit response format (ACK response)
Format name Header Station No. Command
Command
type
Tail Frame check
Frame (Ex.) ACK H20 W(w) SS ETX BCC
ASCII value H06 H3230 H57(77) H5353 H03
Item Description
BCC
When the command is lowercase(r), only one lower byte of the value resulted by adding 1 Byte
each to the ASCII values from ACK to ETX is converted into ASCII and added to BCC, and then
sent.
(4) GM7U main unit response format (NAK response)
Format name Header
Station
No.
Command
Command
type
Error code
(Hex 2 bytes)
Tail Frame check
Frame (Ex.) NAK H20 W(w) SS H4252 ETX BCC
ASCII value H15 H3230 H57(77) H5353 H34323532 H03
Item Description
Frame check
(BCC)
When the command is lowercase(r), only one lower byte of the value resulted by adding 1 Byte
each to the ASCII values from NAK to ETX is converted into ASCII and added to BCC, and then
sent.
Error code Hex and 2 bytes (ASCII code, 4 bytes) indicate error type. For the details, see 8.1.8 Error codes.
(5) Example
This example assumes that “HFF” is written in %MW230 of station no.1 and the BCC value is checked.
①
PC request format (PC → GM7U main unit)
Format name Header Station
No.
Command
Comm
and
type
No. of
blocks
Device
length
Device name Data
Tail
Frame
check
Frame (Ex.) ENQ H01 w SS H01 H06 %MW230 H00FF EOT
BCC
ASCII value H05 H3031 H77 H5353 H3031 H3036 H254D57323330 H30304646 H04
②
For ACK response after execution of command (PC ← GM7U main unit)
Format name Header Station No. Command Command type Tail Frame check
Frame (Ex.) ACK H01 w SS ETX BCC
ASCII value H06 H3031 H77 H5353 H03
③
For NAK response after execution of command (PC ← GM7U main unit)
Format name Header
Station
No.
Command Command type Error code Tail Frame check
Frame (Ex.) NAK H01 w SS Error (2) ETX BCC
ASCII value H15 H3031 H77 H5353 Error (4) H03