| 摘要 |
PURPOSE:To detect automatically a receiving error by amplifying the received data with a carriage, returning to a main card at another light path by the rays of light and comparing the returning data with the transmitting data at every one bit unit by the main card. CONSTITUTION:The data signal sent from the main card 5 to a carriage 2 is sent from a CPU 8 to a light transmitting part 9 as an electric signal, here, converted to a light signal, transmitted to the carriage 2, and received by the light receiving part of a head control part 7 on the carriage 2. After the receiving data signal is amplified by the control part 7, the signal is converted to the light signal again, transmitted from the light transmitting part of the control part 7 through another light path to the light receiving part 10 of the main card 5, and here, converted to the electric signal and sent to the CPU 8. The CPU 8 compares the transmitting data sent to a light transmitting part 9 and the receiving data received at the light receiving part 10 at every one bit unit, and monitors the coincident characteristic. Thus, the malfunction of the printing head due to the light noise of illuminating light, etc., can be monitored without fail. |
