- sales/support
Google Chat: zj734465502@gmail.com
- sales
+86-0755-88291180
- sales01
sales01@spotpear.com
- sales02
dragon_manager@163.com
- support
services01@spotpear.com
- CEO-Complaints
manager01@spotpear.com
- sales/support
WhatsApp:13246739196
- HOME
- >
- ARTICLES
- >
- Common Moudle
- >
- UART Module
Protocol Manual of Modbus RTU Relay User Guide
Command format
The command contains 8 bytes:
- Byte 1：Address
- Byte 2：Function code
- Byte3 4：Address of register (big-endian)
- Byte 5 6：data of register (big-endian)
- Byte7 8：CRC cheksum (little-endian)
Function code
| Function code | Description |
|---|---|
| 01 | Read state of Relay |
| 03 | Read address, revision读 |
| 05 | Write single Relay |
| 06 | Configure baudrate, address |
| 0F | Write all Relays |
Control single relay
command：01 05 00 00 FF 00 8C 3A
| Byte | Meaning | Description |
|---|---|---|
| 01 | Device address | 0x00 is broadcast address；0x01-0xFF are device addresses |
| 05 | 05 Command | Command for controlling Relay |
| 00 00 | Address | The register address of controlled Relay, 0x00 - 0x0008 |
| FF 00 | Command | 0xFF00：Open Replay; 0x0000：Close Relay; 0x5500：Flip Relay |
| 8C 3A | CRC16 | The CRC checksum of first six bytes. |
Answer： 01 05 00 00 FF 00 8C 3A
| Byte | Meaning | Description |
|---|---|---|
| 01 | Device address | 0x00 is broadcast address；0x01-0xFF are dives addresses |
| 05 | 05 Command | Command for controlling relay |
| 00 00 | Address | The register address of controlled Relay,0x0000-0x0008 |
| FF 00 | Command | 0xFF00：Open Relay; 0x0000：Close Relay 0x5500：Flip Relay. |
| 8C 3A | CRC16 | The CRC cheksum of first six bytes. |
Examples： [Device with address 01]: Open Relay 0: 01 05 00 00 FF 00 8C 3A
Close Relay 0: 01 05 00 00 00 00 CD CA
Open Relay 1: 01 05 00 01 FF 00 DD FA
Close Relay 1: 01 05 00 01 00 00 9C 0A
Open Relay 2: 01 05 00 02 FF 00 2D FA
Close Relay 2: 01 05 00 02 00 00 6C 0A
Open Relay 3: 01 05 00 03 FF 00 7C 3A
Close Relay 3: 01 05 00 03 00 00 3D CA
Flip Relay 0: 01 05 00 00 55 00 F2 9A
Flip Relay 1: 01 05 00 01 55 00 A3 5A
Flip Relay 2: 01 05 00 02 55 00 53 5A
Flip Relay 3: 01 05 00 03 55 00 02 9A
Controll all Relay
Command：01 05 00 FF FF FF FC 4A
| Byte | Meaning | Description |
|---|---|---|
| 01 | Device address | 0x00 is broadcast；0x01-0xFF are devices address |
| 05 | 05 command | Command for controlling Relay |
| 00 FF | Address | Fixed 0x00FF |
| FF FF | Command | 0xFFFF：Open Relay； |
| FC 4A | CRC16 | The CRC cheksum of first six bytes |
Answer： 01 05 00 FF FF FF FC 4A
| Byte | Meaning | Description |
|---|---|---|
| 01 | Devices | 0x00 is broadcast address；0x01-0xFF is device address |
| 05 | 05 Command | Command for controlling |
| 00 FF | Address | Fixed 0x00FF |
| FF FF | Command | 0xFFFF：Open Relay； 0x0000：Close Relay； 0x5A00：Flip Relay； |
| FC 4A | CRC16 | The CRC16 checksum of first six bytes. |
Example：
[Device with address 01]:
Open all Relays : 01 05 00 FF FF FF FC 4A
Close all Relays : 01 05 00 FF 00 00 FD FA
Flip all Relays : 01 05 00 FF 5A 00 C7 5A
Read states of all Relays
Command：01 01 00 FF 00 01 CD FA
| Bytes | Meaning | Description |
|---|---|---|
| 01 | Device address | 0x00 is broadcast address；0x01-0xFF are device addresses |
| 01 | 01 Command | Command for checking states of Relay |
| 00 FF | Address | Fixed 0x00FF |
| 00 01 | Command | Fixed 0x0001 |
| CD FA | CRC16 | The CRC16 of the first six bytes |
Answer：01 01 01 00 51 88
| Byte | Meaning | Description |
|---|---|---|
| 01 | Device address | 0x00 is broadcast address；0x01-0xFF are device addressese |
| 01 | 01 Command | Command for checking states of Relay |
| 01 | Number | The number of bytes returned。 |
| 00 | Sate | The state of Relay Bit0:The state of the first Relay； Bit1: The state of the second Relay； Bit2: The state of the third Relay； …… Bit7:The state of the eighth Relay； |
| 8C 35 | CRC16 | The CRC cheksum of first six bytes. |
Examples：
[Device with Address 01]
Command : 01 01 00 FF 00 01 CD FA
Answer: 01 01 01 00 51 88 //Close all Relays
Command : 01 01 00 FF 00 01 CD FA
Answer : 01 01 01 01 90 48 //Open Relay 0号 and close other Relays
Command : 01 01 00 FF 00 01 CD FA
Answer : 01 01 01 41 91 B8 //Open Relay 0 and Relay 6号, close other Relays
Write Relay
Command：01 0F 00 00 00 01 94 0B
| Byte | Meaning | Description |
|---|---|---|
| 01 | Device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 0F | 0F Command | Command for writing Relay |
| 00 00 | Address | Fxied 0x0000 |
| 00 01 | Command | Bit0:Control the first Relay； Bit1:Control the second Relay； Bit2:Control the third Relay； …… Bit7:Control the eighth Relay； |
| 94 0B | CRC16 | The CRC checksum of first six bytes. |
Answer：01 0F 00 00 00 01 94 0B
| Byte | Meaning | Description |
|---|---|---|
| 01 | Device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 0F | 0F Command | Command for controlling all Relay |
| 00 00 | Address | Fixed 0x0000。 |
| 00 01 | Command | 0x0001，Write Relay sate Bit0:Control the first Relay； Bit1:Control the second Relay； Bit2:Control the third Relay； …… Bit7: Control the eighth Relay； |
| 94 0B | CRC16 | The CRC checksum of first six bytes. |
Example：
[Device with address 01]
Open all Relay : 01 0F 00 00 00 FF 15 8B
Close all Relay : 01 0F 00 00 00 00 55 CB
0-1 Open；3-7 Close : 01 0F 00 00 00 03 15 CA
Open/Close Relay in current time
Command：01 05 02 00 00 07 8D B0
| Byte | Meaning | Description |
|---|---|---|
| 01 | Device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 05 | 05 Command | Command for controlling signle Relay |
| 02 | Command | 02 is command for close Relay in current time，04 is command for open Relay in current time |
| 00 | Address of Relay | The address of Relay controlled |
| 00 07 | Delay | The Delay time is Data*100ms Data:0x0007，Delay:7*100MS = 700MS |
| 8D B0 | CRC16 | The CRC checksum of first six bytes. |
Answer：01 05 02 00 00 07 8D B0
| Byte | Meaning | Description |
|---|---|---|
| 01 | Device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 05 | 05 Command | Command for controlling single Relay |
| 02 | Command | 02 is command for close Relay in current time，04 is command for open Relay in current time |
| 00 | Address of Relay | The address of Relay controlled |
| 00 07 | Delay | The delay time is the data*100ms data:0x0007，Delay:7*100MS = 700MS |
| 8D B0 | CRC16 | The CRC checksum of first six bytes. |
Example：
[Device with address 01]
Open Relay 0 : 01 05 02 00 00 07 8D B0 //700MS = 7*100MS = 700MS
Open Relay 1 : 01 05 02 01 00 08 9C 74 //800MS
Close Relay 0 : 01 05 04 00 00 05 0C F9 //500MS
Close Relay 1 : 01 05 04 01 00 06 1D 38 //600MS
Set baud rate
Command：00 06 20 00 00 05 43 D8
| Byte | Meaning | Description |
|---|---|---|
| 00 | 设备地址 | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 06 | 06 Command | Set baud rate or device address |
| 20 00 | Command register | 0x2000: Set baud rate，0x4000:Set device address |
| 00 05 | Baud rate | Baudrate: 0x0000 : 4800 0x0001 : 9600 0x0002 : 19200 0x0003 : 38400 0x0004 : 57600 0x0005 : 115200 0x0006 : 128000 0x0007 : 256000 |
| 43 D8 | CRC16 | The CRC checksum of first six bytes. |
Answer：00 06 20 00 00 05 43 D8
| Byte | Meaning | Description |
|---|---|---|
| 00 | Device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 06 | 06 Command | Set baud rate or device address |
| 20 00 | Command register | 0x2000: Set baud rate，0x4000 Set device address |
| 00 05 | Baud rate | The baud rate 0x0000 : 4800 0x0001 : 9600 0x0002 : 19200 0x0003 : 38400 0x0004 : 57600 0x0005 : 115200 0x0006 : 128000 0x0007 : 256000 |
| 43 D8 | CRC16 | The CRC checksum of first six bytes. |
Example：
[Device with address 0x01]
Set baud rate as 4800 ：00 06 20 00 00 00 83 DB
Set baud rate as 9600 ：00 06 20 00 00 01 42 1B
Set baud rate as 115200 ：00 06 20 00 00 05 43 D8
Set device address
Command：00 06 40 00 00 01 5C 1B
| Byte | Meaning | Description |
|---|---|---|
| 00 | Device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 06 | 06 Command | Set baud rate or device address |
| 40 00 | Command register | 0x2000: Set baud rate，0x4000: Set device address |
| 00 01 | Device address | The device address,0x0001-0x00FF |
| 5C 1B | CRC16 | The CRC checksum of first six bytes. |
Answer：00 06 40 00 00 01 5C 1B
| Byte | Meaning | Description |
|---|---|---|
| 00 | Device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 06 | 06 Command | Set baud rate or device address |
| 40 00 | Command register | 0x2000: Set baud rate，0x4000:Set device address |
| 00 01 | Device address | Set device address,0x0001-0x00FF |
| 5C 1B | CRC16 | The CRC checksum of first six bytes. |
Example：
[Device with address 0x01]
Set device address as 0x01 ：00 06 40 00 00 01 5C 1b
Set device addrss as 0x02 ：00 06 40 00 00 02 1C 1A
Set device address as 0x03 ：00 06 40 00 00 03 DD DA
Read device address
Command：00 03 40 00 00 01 90 1B
| Byte | Meaning | Description |
|---|---|---|
| 00 | Device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 03 | 03 Command | Read Device address |
| 40 00 | Command register | 0x0200: Read software revision，0x0040: Read device address |
| 00 01 | Device address | Device address |
| 90 1B | CRC16 | The CRC checksum of first six bytes. |
Answer：01 03 01 01 31 88
| Byte | Meaning | Description |
|---|---|---|
| 00 | Device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 03 | 03 command | Read software revision or device address |
| 01 | Number of bytes | Number of bytes returned |
| 01 | Device address | Devicess |
| 31 88 | CRC16 | The CRC checksum of first six bytes. |
Example:
[Device with address 01]
Command : 00 03 40 00 00 01 90 1B
Answer : 01 03 01 01 31 88 //地址0x01
[Device with address 02]
Command : 00 03 40 00 00 01 90 1B
Answer : 02 03 01 02 71 CD //地址0x02
[Device with address 03]
Command : 00 03 40 00 00 01 90 1B
Answer : 03 03 01 03 B1 F1 //地址0x03
Read software revision
Command：01 03 20 00 00 01 8F CA
| Byte | Meaning | Description |
|---|---|---|
| 01 | device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 03 | 03 Command | Read software revision or device address |
| 20 00 | Command register | 0x0200: Read software revision，0x0040: Read device address. |
| 00 01 | Device address | Device address |
| 8F CA | CRC16 | The CRC checksum of first six bytes. |
Answer：01 03 01 64 F1 A3
| Byte | Meaning | Description |
|---|---|---|
| 01 | Device address | 0x00 is the boradcast address；0x01-0xFF are device addresses |
| 03 | 03 Command | Read software revision, read device address |
| 01 | Number of bytes | number of bytes returned |
| 64 | Revision of Software | Convert it to DEX and multiply by 0.01 is the value of software revision.
|
| F1 A3 | CRC16 | The CRC checksum of first six bytes. |
Example：
Command：01 03 20 00 00 01 8F CA
Answer：01 03 01 64 F1 A3 // 64 = 100 =V1.00
