Uses the advanced industrial STC80C51 one-chip computer; stability and optimization. High electromagnetic compatibility design; conforms to international related standard, and good anti-interference ability. Uses surface mounting technique and highly conglomerated circuit board, can avoid communication breakdown caused by connection. Among the input and output port (as well as the signal place) can get driving and electronic isolation by optocoupler. Has the signal light display for signal receiving and carrier wave inspection indicative status; Complete metal cabinet, industrial design, artistic modeling, and convenient screen combination; Reliable product quality, small volume, and convenient design; With card model (may share the smc2000 cabinet with SMC serial power modem driver.