User`s manual

FX communication
Commands 8
8-2
8.1 Batch Read of Bit Device (BR command)
1 ) Command specification
Protocol format 1 is shown.
2 ) Command example
To read five points of data from X040 to X044 at station No.5 (with message wait time set to
100 ms).
(Assuming that X040 and X043 are OFF and X41, X42 and X44 are ON)
Computer
Programmable
controller
E N Q
Station No. PLC No.
B R
Message wait time
Sum check code
Station No.
S T X
PLC No.
Data of
the
specified
devices
E T X
Sum check code
Station No.
A C K
PLC No.
Character area B
Batch read command (bits)
Head device
(5 characters)
Number of
devices
(2 characters,
hexadecimal)
Specifies the range of
devices to be read.
"0" (30H) indicates OFF.
"1" (31H) indicates ON.
Character area A
Notes
• Specify the range and number of devices so as to satisfy the following conditions.
-1
≤
number of devices
≤
256(54 for FX
0N
)(256 points are specified by 00H)
- Head device No. + number of devices -1
≤
max. device No.
• The station number, PC (PLC) number, number of devices, and sum check code are
expressed in hexadecimal.
Computer
Programmable
controller
E
N
Q
The sum check is calculated
over this range
The sum check is calculated
over this range
35H30H
0 5
46H46H
F F
52H42H
B R
41H
A
58H 30H34H30H30H 35H30H
X 0 0 4 0
0 5
37H34H
4 7
05H
S
T
X
35H30H
0 5
46H46H
F F
02H
0 1 1 0 1
30H 31H30H31H31H
E
T
X
35H30H
0 5
03H
A
C
K
35H30H
0 5
46H46H
F F
06H
Indicating X044 is ON
Indicating X042 is ON
Indicating X043 is OFF
Indicating X040 is OFF
Indicating X041 is ON
Notes
• Message wait time can be specified from 0 to 150 ms in 10 ms increments, expressed
by 0H to FH (in hexadecimal).
Therefore, 100 ms is expressed as “A”.