Feature: 1. This is an 8 channel 12V relay output board module, with 8 optocoupler isolated inputs and outputs 2. Relay has low power consumption, high accuracy, and adopts RS485 TTL communication interface 3. The 8 Channel 12V relay adopts portable design, simple operation and easy installation 4. The power terminal interface is 12V power supply, which is very convenient to use in daily life 5. Can be used for smart home control, mobile phone or computer remote control lights Specification: Item Type: Relay Output Board Module Size: Approx. 143 x 67mm / 5.6 x 2.6in Communication Interface: RS485, TTL Input and Output: 8 Channel Optocoupler Isolation Button: Reset Button, User Button Indicator Light: User LED Indicator, Power Indicator MCU: STM8S103K Relay Status Indicator LED Lights: 8 DC Power Socket: 12V Power Supply Power Terminal Interface: 12V Power Supply RTU instruction Baud Rate: 9600 8 NONE 1 Hexadecimal sending Hex receiving Steps: 1. The software sets the communication baud rate 2 Set the address (the device address used for communication, the default address is 01) Set The Address As: 09 01 10 00 00 00 01 02 00 09 66 56/Address 01 is changed to 09 Set The Address As: 01 01 10 00 00 00 01 02 00 01 66 56//modify to 01 Read address 00 03 00 00 00 01 85 db Return: 00 03 02 00 01 44 44 //01 is the address The Meaning Of Each Byte: 【Number Address】 1 Electrical Appliances Are Turned On: 01 05 00 01 01 00 9d 9a Byte 1: Address Byte 2: Function? Byte 3 4: Register address Byte 56: Register data Byte 78: CRC check [Address No. 1] 0 Appliances Are Turned On: 01 05 00 00 FF 00 8C 3A No. 0 Relay Is Off: 01 0500 0000 00 CD Relay No. 1 Is On: 01 05 00 01 FF 00 DD FA Relay No. 1 Is Closed: 01 05 00 01 00 00 9C OA Relay No. 2 Is On: 01 05 00 02 FF 00 2D FA Relay No. 2 Is Closed: 01 05 00 02 00 00 6C OA Relay No. 3 Is On: 01 0500 03 FF 00 7C 3A Relay No. 3 Is Off: 01 05 00 03 00 00 Relay No. 4 Is On: 01 05 00 04 FF 00 CD FB Relay No. 4 Is Closed: 01 05 00 04 00 00 8C Relay No. 5 Is On: 01 05 00 05 FF 00 9C 3B Relay No. 5 Is Closed: 01 05 00 05 00 00 DD CB Relay No. 6 Is On: 01 05 00 06 FF 00 6C 3B Relay No. 6 Is Closed: 01 05 00 0600 00 2D CB Relay No. 7 Is On: 01 05 00 07 FF 00 30 FB Relay No. 7 Is Closed: 01 05 00 07 00 00 7C 0B All Off: 01 0F 00 00 00 08 01 00 FE 95 All On: 01 0F 00 00 00 08 01 FF BE D5 . Package List: 1 x Relay Module