| 摘要 |
PURPOSE:To make it possible to discriminate the transmission error of printing information, by providing a circuit for bypassing the transmission part of an ink jet recording apparatus by connecting a transmitting circuit and a receiving circuit and controlling the same by a bypass circuit control part. CONSTITUTION:Printing information of an external apparatus 7 is transmitted to the terminal Rx of ACiA4 through the receiving circuit 6 of an ink jet printer IJP18 and, at the same time, returned to the external apparatus 7 through the gate circuit 16 and the transmitting circuit 5 of a bypass circuit 14 controlled by the control signal EMG from LSI13 to perform collimation. If not same, it is detected that the abnormality of a transmission line 20 itself is generated. The printing information received by ACiA4 is inspected with respect to the presence or absence of a transmission error and, if there is an error, printing information is not returned and, therefore, the external apparatus 7 judges the transmission error to stop the transmission of printing information. |
