| 摘要 |
PROBLEM TO BE SOLVED: To provide a signal changeover device that can switch communication channels with a simple configuration. SOLUTION: The signal changeover device is provided with a decoder 1 that gives a transmission data signal TXD and a communication control signal RTS or DTR to each input terminal, sequentially outputs a level of the transmission data signal in response to a level of the communication control signal to output terminals as output signals and uses an optional output signal for a serial data communication output and with a shift register 2 that uses the other output signals of the decoder 1 for latch signals, gives either of the communication control signals to each input terminal as a shift clock signal or a data signal, uses the shift clock signal to sequentially shift the level of the data signal, uses the latch signals to latch the data signal and provides a prescribed parallel data output from an input terminal. |
