| 摘要 |
PURPOSE:To prevent an ommision defect in printing due to noise, by outputting an alarm signal when the potential at the coupling point of the drive coil of a printing pin with a driving element reaches a predetermined value. CONSTITUTION:When data is inputted in a printing control circuit 1, printing data is supplied at every drivers Q1-Qn of coils L1-Ln driving each printing pins while a printing timing pulse G is inputted in a timer 2 to generate a printing signal P in the output therefrom. In addition, the collector potential of each driver is introduced into a comparator 8 by an OR circuit constituted from diodes D1-Dn to be compared to reference potential. This comparing time is determined by a timer 5 and a pulse generating circuit 6. When the potential of the input signal of the comparator 8 becomes different from the reference potential, the output signal of an AND circuit 7 is not obtained. Therefore, this state is discriminated by the circuit 1 and re-printing or the outputting of an alarm is carried out. |
