| 摘要 |
PURPOSE:To reduce the possibility that writing into a dot memory conflicts with reading from the dot memory, by providing memory request control flags in the dot memory on a line basis or a raster basis, in a printer controller. CONSTITUTION:When a command for starting reading is outputted from a raster-controlling circuit 111 to a memory request control flag bit reading circuit 112, a request for reading is outputted to a full bit memory 100 through an OR circuit 114, an address is outputted to a memory bus 120, and a detecting command is outputted to a memory request control flag bit detecting circuit 113. When a memory request control flag bit on the bus 120 is '0', the detecting circuit 113 outputs a command for starting reading, and a memory request controlling circuit 115 reads dot data from the memory 100 according to a reading command from a dot data output controlling circuit 116. When the control flag bit is '1', a command for outputting dot data is not outputted. Accordingly, the possibility of conflict of writing with reading is reduced, and high-speed printing control can be performed.
|
