4
MODBUS(R) STANDARD FUNCTIONS
4.14 Write Multiple Coils (FC: 15)
4 - 50
1
OVERVIEW
2
SYSTEM
CONFIGURATION
3
SPECIFICATIONS
4
MODBUS(R) STANDARD
FUNCTIONS
5
FUNCTION
6
PRE-OPERATIONAL
PROCEDURES AND
SETTINGS
7
PARAMETER SETTING
8
UTILITY PACKAGE
(GX Configurator-MB)
4.14 Write Multiple Coils (FC: 15)
Writes values (ON/OFF) to multiple coils.
(1) Request message format (Master Slave)
* 1 The number of the specified write points must be matched with the number of bits specified as the
number of bytes.
For example, when the write points are set to 16, set the number of bytes to 2 bytes (= 16 bits).
Figure 4.82 Write multiple coils (Request message)
Data
(L) (L)
. . .
b0b1b2b3b4b5b6b7
Function code
Function
code
(0F
H)
Head coil number
(0000
H to FFFFH)
Write points*1
(0001
H to 07B0H)
Number of
bytes n*1
(0001
H to
00F6
H)
Device
data
1
Device
data
n
(Number of bytes n)
(Device data 1 to n )
Device data 1
Device data n
Data storage order
0 : OFF
1 : ON
The values (ON/OFF) stored into the device data 1 to n are written to
the coils in order from low-order to high-order bits of the device data.
(H)
(H)