E850-DTU(4440-GPRS) datasheet
Copyright ©2012–2018
，成都亿佰特电子科技有限公司
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01
0F
00 11
00 02
01
03
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Device
ModBus
address
Function
code
Switch
quantity
address
Write
number of
switch
quantity
Bytes
Write
value
CRC
code
Receive
01
0F
00 11
00 02
84 0F
Device ModBus
address
Function
code
Switch
quantity
address
Write value
CRC code
Modbus TCP protocol write switch output:
Send
00 01
00 00
00
08
01
0F
00 11
00 02
01
03
Transm
ission
identifie
r
Protoco
l
identifie
r
Len
gth
Unit
identifier
Funct
ion
code
Switch
quantity
address
Write
number of
switch
quantity
Bytes
Write
value
Recei
ve
00 01
00 00
00
06
01
0F
00 11
00 02
Transm
ission
identifi
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Protoc
ol
identifi
er
Leng
th
Unit
identifier
Funct
ion
code
Switch quantity
address
Write number of
switch quantity
4.2.2 Read switch quantity DI input
Function: 02, Read switch quantity input state
Address range: 10017(0x0010)~10020(0x0013)
Note: The device default dry contact input. When DI and COM are shorted, the read value should
be 1; when DI and COM are not shorted, the read value should be 0.
For example:
Reading 4 channel switch input value, DI1 and COM1 are shorted, DI2 and COM2 are not shorted,
DI3 and COM3 are shorted, DI4 and COM4 are not shorted. The input switch value is 0x05,
corresponding to the binary bit 0000 0101, and the lower four bits represent the switch input value,
which are in turn DI4, DI3, DI2, DI1.
Modbus RTU protocol read switch input:
