| 摘要 |
PURPOSE:To enable the use of the same character generator in the printing characters having different pitches and to reduce a printing position error, by generating printing timing signals at different pitches. CONSTITUTION:In the movement of a carriage, printing timing signal is outputted from an encoder at a fixed interval and used as a reference signal. a programmable frequency dividing circuit 50 divides the frequency of an encoder signal 7 to 1/N on the basis of the frequency dividing value signal 52 from a microprocessor for performing the main control of a printer. In the same way, a programmable frequency dividing circuit 51 divides the frequency of the output signal 56 of a voltage control type variable frequency oscillator 55 to 1/M on the basis of the frequency dividing value signal 52. The phase difference between frequency divided output signals 57, 58 is outputted as a pulse width signal 59 by a phase difference detector 53. A filter circuit 54 for converting the pulse width signal to an analogue voltage signal 60 is a low band-pass filter. The analogue voltage proportional to said phase difference is applied to the voltage control type variable frequency oscillator 55 and sent to a microprocessor for main control as a printing timing signal 56. |
