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8.
COMMUNICATIONS USING DEDICATED PROTOCOLS
MELSEC-A
(b) Using the JR command (AnACPU dedicated command)
lesianation ~ e t h o d l
St. No.
:
Station number
Designation in protocol 1 is shown below.
Batch r - q (bit) command
Character area A
\
1
.
.
I
0 (30H) indics
wca.x,m
Designation of device
, ,
I
e g n a s l n u m b e r
I
range to be read
1 1
$k.
1
NO.
POINT
To designate the device range, the following conditions must be met:
.
1
5
number of device points a 256 (setting for 256 points is OOH)
(Head device number)
+
[(number of device points)
-
11
s
maximum
device number
lesignation Example1
To read the data at
5
points from X40 to X44 in PC NO. "01
".
(Message wait time is
100 msec.) (Assume that X40 and X43 are OFF and X41, X42, and X44 are ON.)
Check sum is calculated
O O 1 J R A X O O O O 4 O
0
5
7
F
within this range
, n . & , a . ~ , r a ,
a.
% , ~ ~ & , % , & , Y * , X L .
n . ,a
n.,
is.
4
4
.
AlSJ71 C24
Check sum is calculated
E
within this range
O
1
t
O
1
T 8 7
X
Y k l l l ~ , I I ~ , 3 k c &
(L4
4&&
t t t t t
lndicates that X44
is
ON
lndicates that X43 is OFF
lndicates that X42 is ON
lndicates thatX41 is ON
lndicates that X40 is OFF
POINTI
The message wait time is designated in the range of 0 to 150 msec i n units
of 10 msec, using hexadecimal notation of 0 to FH. Therefore, 100 msec
corresponds to "A".
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