Auto RS232 / RS485 Communication Converter

摘要

The present disclosure relates to an automatic RS232 / RS485 communication converter that automatically converts an RS232 signal into an RS485 signal using only a transmit / receive signal without using a control signal (/ RTS). This invention comprises a clock generation circuit for determining the communication speed used in the RS232 and RS485 method to generate a clock equal to the communication rate determined by the user; A transmission data shift register synchronously delaying the transmission data input from the RS232 transmission data input processing terminal for a predetermined time in synchronization with a clock generated by the clock generation circuit; A transmission data detection circuit for generating a signal for switching to a transmission mode when the transmission data is input, and for sending a transmission / reception control signal for switching to the reception mode if the transmission data is not input for a predetermined time using a clock generated by the clock generation circuit; And an RS485 transmit / receive data processing stage that switches to the transmit state only when the transmit / receive control signal inputted from the transmit data detection circuit is the transmit mode change signal, and is maintained in the receive state in the normal state. By such a configuration, the present invention has an effect of more stably maintaining the system by not requiring separate control software by implementing automatic switching between the two communication methods in hardware. Therefore, the present invention will ultimately improve the quick accuracy of the transmission and reception data and the reliability of the communication device.