PRINTER CONTROL APPARATUS

PURPOSE:To achieve the miniaturization and wt. reduction of a printer control apparatus for magnifying and contracting an image, by performing magnification and contraction in the longitudinal direction by the processing of a reading address and that in the lateral direction by reading a memory on the basis of a clock. CONSTITUTION:When an IO processor 18 detects the finish of the DMA printing of one line, the address of the next data to be printed is set to an address counter 20 and a number-of-word counter 26. When a DMA start address is set to A and the number of the words of one line are set to l, the N-th set address is set to A+lX(N-1)Xn/m at the time of magnification of m/n times in the longitudinal direction. A counter 3 counts the fundamental clock obtained by the (m) frequency division of the output of an n-time oscillator 7 by an (m) frequency dividing counter 8. Phase matching is performed in synchronous relation to a horizontal synchronous signal HSYNC to output an n/m-time clock. When the (m) frequency dividing counter is connected to a bus so as to be capable of being set from the IO processor 18, the magnification rate in the lateral direction can be changed.