Protocol: LC USB switch default communication baud rate: 9600 bps. LC USB Switch Communication Protocol: Data (1): Starting identifier (default: 0xA0) Data (2): Switch address code (default: 0x01, identified as the first switch) Data (3): Operation data (0x00 = OFF, 0x01 = ON) Data (4): Check code Example: Turn ON: A0 01 01 A2 Turn OFF: A0 01 00 A1 How to Use: 1. Plug the USB relay into the computer and install the CH340 serial port driver. 2. Open serial debugging software such as STC-ISP or SSCOM32, set baud rate to 9600, and send “A0 01 01 A2” in hexadecimal format to turn the relay ON; send “A0 01 00 A1” in hexadecimal format to turn the relay OFF. USB intelligent control switch. Onboard high-performance microcontroller chip. Onboard CH340 USB controller chip. Onboard Power LED and relay status LED. Onboard 5V, 10A / 250VAC, 10A / 30VDC relay; relay life: 100,000 cycles. Relay modules include overcurrent protection and freewheeling diode protection. Color: Blue Material: PCB Size: 49.6 × 16 mm Package Contents: 1 × USB relay module Note: Lighting conditions and display differences may cause slight color variation between the image and the actual product. Measurement tolerance: ±1–3 mm.