| 摘要 |
<p>A timing pulse generator for a serial printer, which generator outputs a print timing pulse at a timing necessary for accurately controlling movement of the print head. In this timing pulse generator, an edge detection circuit outputs a pulse signal each time it detects the rising edge of an encoder signal output in response to movement of the carriage. A timer circuit measures the pulse period between two succeeding pulse signals output from the edge detection circuit. A first storage circuit outputs the stored previous pulse period and overwrites the storage area with this new pulse period. A second storage circuit outputs the stored pulse period immediately before the previous pulse period and overwrites the storage area with the previous pulse period output from the first storage circuit. A subtraction circuit calculates the difference between the previous pulse period and the pulse period immediately before the previous pulse period, after which an addition circuit adds this difference to the previous pulse period to obtain an estimated value of a pulse period equivalent to the current velocity of the carriage. Finally, the estimated value is divided by a prescribed value based on the printing resolution to generate the print timing pulse that provides the print head drive timing. <IMAGE></p> |
