Abstract: A method for parallel data transmission in a system having (i) a modem, (ii) one or more modem status terminals which detect modem status information and are connected to the modem, (iii) one or more modem control terminals which transmit modem control signals and are connected to the modem, and (iv) one or more serial signal output terminals which receive line control signals and are connected to the modem. Data signals are output via the one or more modem control terminals. Signal logic levels of these output data signals are controlled in accordance with the modem control signals. Data signals are also output via the one or more serial signal output terminals. The signal logic levels of these later output data signals are controlled in accordance with the line control signals. Data signals are input via one or more modem status terminals. The signal logic levels of the input data signals are perceived in accordance with the modem status information.

Abstract: A data communication system between computers comprises communication paths composed of m transmission lines between the computers. Data and data to be transferred is coded based on a coding table. Each code comprises a series or string of figures. Each figure has a numeric value not over the m-th power of 2. Also, those adjacent figures in each code string have necessarily different values. Coded data is transmitted figure by figure through m transmission lines. Since values of each figure in a code necessarily differ, a timing signal is not required.