| 摘要 |
PURPOSE:To diagnose the hardware including full-duplex and semi-duplex communication at each line, by performing the control and monitor of an MODEM interface signal line per a line and the confirmation of operation of a transmission and reception control function of data internally. CONSTITUTION:A data transmission and reception circuit 7i including a control circuit and a monitor circuit of an MODEM interface signal line per each line 10i is mutually connected at a self-line folding circuit 9i, and transmission/ reception data are respectively stored per each line on a memory 4 and a memory 5 is provided a function comparing each data of transmission and reception of the memory 4. Through the test instruction from a CPU1, the control and monitor of the MODEM interface signal line is performed and a data from the CPU1 is stored in the memory 4 and sequentially transmitted from a transmission line, and this transmission data is received via the circuit 9i and compared with the transmission data in the memory 4. The result of control and monitor of the MODEM interface signal line and the result of comparison of data are informed to the CPU1. |
