| 摘要 |
PURPOSE:To enlarge and reduce character and pattern with a simple circuit constitution, by varying the clock ratio when the contents of a data register of character and pattern are transferred to the side of a pattern buffer memory. CONSTITUTION:The data on the character and pattern sent from a central processor are stored in a data register 1, and at the same time the commands for enlargement and reduction are sent to a clock control circuit 2 from the central processor. The circuit 2 receives the clock from a clock generator 7 and divides and multiplies the clock. Then the circuit 2 selects a clock by a command and sends it to a register control circuit 3. The circuit 3 sets the ratio at 1:2, 2:1, 3:1, etc. for example between the cycles of the data reading clock given from the register 1 and the data writing clock to be given to a shift register 4. The enlarged or reduced data in a register 4 is supplied to a printer 6 via a pattern buffer memory 5. |
