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Chapter 7 Communication function
7-74
1)
Request format(PC -> PLC)
Format
Name
Header
Station No.
Command
Command type
PI_N_LEN
PI_N_NAME
Tail
Frame
check
Frame (Ex.)
ENQ
H10
M(m)
RN
H04
LGIS
EOT
BCC
ASCII value
H05
H3130
H4D(6D)
H524E
H3034
H4C474953
H04
9
PI_N_LEN is where the number of PI name’s characters is displayed.
9
PI_N_NAME is where PI name is displayed.
9
When PI name is executed as specified, the max.number of characters is 16.
9
If no name is required, use D instead of N in command type. If D has been used, PI_N_LEN and
PI_N_NAME are unnecessary.
9
PI_N_NAME shall be the name to specify or default name of ‘P_Program’.
9
BCC : When command is one of lower case(m), only one lower byte of the value resulted by adding 1 byte
each to ASCII values from ACK to ETX is converted into ASCII, added to BCC, and sent.
[Table 7.22] Command type
RN(D)
Starts PLC start-up(RN = PI name, RD= Default)
PN(D)
Temporarily stops what is in operation. (PN = PI name, PD= Default)
SN(D)
Switches temporarily stopped PLC to program mode (stops it). SN = PI name, SD = Default
EN(D)
Restarts temporarily stopped PLC. (EN = PI name, ED= Default)
2)
Response format(for PLC of ACK response)
Format
Name
Header
Station No.
Command
Command type
Tail
Frame check
Frame (Ex.)
ACK
H10
M(m)
RN
ETX
BCC
ASCII value
H06
H3130
H4D(6D)
524E
H03
9
Station number, commands, and type of command are the same as in computer request format.
9
BCC : When command is one of lower case(m), only one lower byte of the value resulted by adding 1 byte
each to ASCII values from ACK to ETX is converted into ASCII, added to BCC, and sent.