Brief introduction: TTL to module, TTL signal and signal optocoupler isolation, no interference, receiving circuit from the bus power, do not need to power alone, but because the TTL signal and signal optocoupler isolation, so optocoupler needs to power alone! The module adopts FC722 slave chip, which is stable and strong anti-interference. The ultra small volume is easy to install with any equipment! Color: green Material: PC+Metal Main parameters: 1. Communication baud rate: 300-9600bps 2, TTL signal: compatible with 3.3V, 5V, or other 3. The bus voltage 12V-42V can be adapted 4. Bus current 200uA - 3mA continuous 5, VIN:TTL signal voltage value (if TTL is 3.3V, VIN input 3.3V voltage; TTL is 5V, VIN input 5V voltage). 6, data interface: TXD connects to external TXD; RXD connects to external RXD. 7, there is no spontaneous self collection (TSS721 internal Uart is a closed loop, so there is spontaneous spontaneous phenomenon, and this module does not). Application areas: 1, application of analog intelligent water meter air meter caloric meter reading 2. Application of analog smart grid automatic meter reading 3. The application of analog intelligent home control network 4. Simulation of fire alarm and the application of linkage network 5, simulation of the application of central air conditioning control system 6. Application of analog intelligent sensor network Package Contents: 1 x serial port to slave module Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.