Chapter 7 Communication function
1 Continuous reading of direct variables (RSB)
This is a function to read PLC device memory directly specified in accord with memory data type.
It is convenient command to continuously read data up to 120 bytes in continuous areas from the specified
address.
1) Request format(PC -> PLC)
Format
Header
Name
Frame(Ex.)
ENQ
ASCII value
H05
Remark
[Note 1] Number of data specifies the number
variable is double word and the number of data is 5, it means that 5 double
BCC : When command is one of lower case(r), only one lower byte of the value resulted by adding 1 byte
each to ASCII values from ENQ to EOT is converted into ASCII and added to BCC.
Name length of direct variable : This indicates the number of name's characters that means direct variable,
which is allowable up to 16 characters. This value is one of ASCII converted from HEX type, and the range
is from H01(ASCII value:3031) to H10(ASCII value:3130).
Direct variable : It means address of variable to be read actually in ASCII value within 16 characters. Others
than figure, upper/lower cases, '%' and '.' are not allowed for this variable name. Variable type available for
continuous reading of direct variables is as follows according to PLC type.
[Table7.17] Continuous variable area available to read
Classification
GM1
GM2
GM3
GM4
GM6
GM7
Station
Command
Command
No.
type
H10
R(r)
SB
H3130
H52(72)
H5342
according to the type of direct variable. Namely, if data type of direct
BOOL
Byte
-
%MB,%QB,%IB
-
%MB,%QB,%IB
-
%MB,%QB,%IB
-
%MB,%QB,%IB
-
%MB,%QB,%IB
-
%MB,%QB,%IB
7-46
Variable
Variable
Number of data
length
name
(Max.120 byte)
H06
%MD100
H254D44
H3036
313030
WORD
DOUBLE WORD
%MW,%QW,%IW
%MD,%QD,%ID
%MW,%QW,%IW
%MD,%QD,%ID
%MW,%QW,%IW
%MD,%QD,%ID
%MW,%QW,%IW
%MD,%QD,%ID
%MW,%QW,%IW
%MD,%QD,%ID
%MW,%QW,%IW
%MD,%QD,%ID
Frame
Tail
check
H05
EOT
BCC
H3035
H04
words shall be let read.
LONG WORD
%ML,%QL,%IL
%ML,%QL,%IL
-
-
-
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