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King Pigeon Hi-Tech. Co., Ltd.
Ver 1.3
GSM/SMS/GPRS/3G/4G
Cellular IoT Gateway
If control relay status which connected to RS485, need to add slave in salve list of configurator. Write
command 15 for mapping, when mapping address value modified, will write to RS485 matched slave address.
Master Send Data Format:
Content
Bytes
Data
(H: HEX)
Description
Device Address
1
01H
01H Device, Range: 1-247, according to setting address
Function Code
1
05H
Write single holding coil, function code 05H
Boolean Mapping
Register Address
2
00 40H
Range: 00 40H-00 7FH, address refer to
Mapping Register Address”]
at manual bottom
Write value
2
FF 00H
This value: FF 00H or 00 00H, FF 00H stands for write 1;
00
00H stands for write 0
16 CRC Verify
2
8D EEH
CRC0 CRC1 low byte in front, high behind
Receiver Return Data Format:
Content
Bytes
Data
(H: HEX)
Description
Device Address
1
01H
01H Device, according to the data Master send
Function Code
1
05H
Write single holding coil
Boolean Mapping
Register Address
2
00 40H
Range: 0040H-007FH
Write value
2
FF 00H
This value: FF 00H or 00 00H. FF 00H stands for write
1,00 00H stands for write 0.
16 CRC Verify
2
8D EEH
CRC0 CRC1 low byte in front, high behind
Example: Modify Boolean mapping address 64 status, modify to 1, then:
Server send:
01 05 00 40 FF 00 8D EE
01= Device address; 05= Write Boolean value; 00 40=The mapping address which need to revise; FF 00 = Write
1;
8D EE = 16 Bit CRC verify.
Device answer:
01 05 00 40 FF 00 8D EE
01= Device address; 05= Write Boolean value; 00 40= The mapping address which need to write; FF 00= Write
1.
8D EE = 16 Bit CRC verify.
If need multi modify, pls check function 15 of Modbus protocol.
8.4.3 Read Data Type Mapping Address Data:
Master Send Data Format:
Content
Bytes
Data
(H: HEX)
Description
Device Address
1
01H
01H Device, Range: 1-247, according to setting address
Function Code
1
03H
Read holding coil, function code 03
