SERIAL SIGNAL TRANSMITTER

PURPOSE:To test an abnormal operation by intentionally preparing an abnormal signal at the time of transmission and reception. CONSTITUTION:When transmission is started after the numbers of characters and bits are designated by setting units 8 and 13, normally, a serial signal is outputted from an LSI 1 for communication to a driver 3 and when the numbers of characters and bits in the serial signal are matched with the designated numbers of characters and bits, corresponding to the instruction of a control circuit 9, a selector 6 outputs a bit inverted signal in the character to the driver. When reception is started, normally, a serial signal is outputted from a receiver 4 to the LSI 1 for communication and when the numbers of characters and bits in the serial signal match the designated numbers of characters and bits, corresponding to the instruction of a control circuit 14, a selector 11 outputs a bit inverted signal in the character to the LSI for communication.