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8. COMMUNICATIONS
USING DEDICATED PROTOCOLS
MELSEC-A
8.7.5
Batch write in units of words
(a) Using the WW command (ACPU common command)
lesignation Methodl
St. No. :Station number
Designation in protocol 1 is shown below.
Character area C
Computer
/
Designation of device range to be read
Batch read
(word) command
1 point of the device uses 4 characters.
Therefore, a 1-word data is expressed in
St
Na
HIL
4 digits (hexadecimal).
To designate the device range, the following conditions must be met:
1
I
number of device points
5
64 (10 for a bit device)
(Head device number)
+
[(number of device points**)
-
I ]
5
maximum
device number
**("number of device points" x 16 for a bit device)
,
a
,
PC
No.
H I L
esignation ~ x a m ~ l e s (
f
I
Example 1 :
To write data to 32 points from M640 to M671 in station "0".
(Message wait time is 0 msec)
I
I
I
I
I
I
0 6 4 0 0 2 2 3 4 7 ; A 8 9 6 0 5
, Y ~ , J I ~ I I ~ , u ~ , R . , H ~
~ v , U ~
,
AJ71 C24
.
Check sum is calculated
within this range
C
O O F F
06-
1 0 . &
4.,46.
2
1
3
1
4
1
7
9
I
B
M M M
M M M M M M M
M M M M
.-........-......
4 4 4 4 7 7 6
6 6 6 6 6 5 6
-..-..-.......-..
6 6 6 6
5
4
3
5 5 5 5
3 2 1 0 1 0 9
9 8 7 6
! % %
The WW command is used for word unit designation. The designation
for the number of device point to write data to the 32 points to M640 to
M671 is "02" ("I"
for 16 points).
,
, , ,
Head dwice
(scharaaers)
I
I I
I
Number of
device poi&
pcharaaerp
(nexade4mal)
DataformedeSi
nated numberx
dense poinb
pDcrignatednum-
~ r a f a e v i c e points.
x4chamctem)
Sum
Sode
H I L
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