Chengdu Ebyte Electronic Technology Co.,Ltd
E821-RTU (0400-ETH)User Manual
Copyright ©2012–2019, Chengdu Ebyte Electronic Technology Co.,Ltd
19
19
n identifier
identifier
identifier
n code
Receive
00 01
00 00
00 09
01
03
06
1A 00 1C C0 BB
FF
Transmissio
n identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Number of bytes
Read value
Note: 1A 00 1C C0 BB FF is the MAC address of the device, the device has a unique MAC address.
4.3.2 Device SN code reading
Modbus RTU protocol read register:
Send
01
03
01 65
00 04
55 EA
Device ModBus
address
Function
code
Start address
Read number of
registers
CRC check code
Receive
01
03
08
19 05 21 14 00 13 55 50
F9 AA
Device ModBus
address
Function
code
Number of
bytes
Read value
CRC check code
Modbus TCP protocol read register:
Send
00 01
00 00
00 06
01
03
01 65
00 04
Transmissio
n identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Address
Read number
Receive
00 01
00 00
00 0B
01
03
08
19 05 21 14 00 13 55 50
Transmissio
n identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Number
of bytes
Read value
Note: 19 05 21 14 00 13 55 50 is the device SN code, the devices have different SN codes.
4.3.3 Network function parameter validation command (Ethernet restart command)
Modbus RTU protocol write register:
Send
01
06
00 67
00 01
F9 D5
Device ModBus
address
Function
code
Address
Write value
CRC check code
Receive
01
06
00 67
00 01
F9 D5
Device ModBus
address
Function
code
Address
Write value
CRC check code
Modbus TCP protocol write register:
Send
00 01
00 00
00 06
01
06
00 67
00 01
Transmission
identifier
Protocol
identifier
Length
Unit
identifier
Functio
n code
Address
Write value