| 摘要 |
PROBLEM TO BE SOLVED: To perform fast image rotation processing with a simple configuration while using an inexpensive memory element such as an SDRAM. SOLUTION: When a DMA controller 10 accesses 1st to 3rd printer buffers 6 to 8 under the control of a CPU 1 in order to perform data transfer among a scanner controller 3, a printer controller 5, a rotation register 9 and the 1st to 3rd printer buffers 6 to 8, the controller 10 uses a DRAM address obtained by making the low order four bits C0 to C3 of a column address correspond to respective bits of CPU addresses A1 to A4, the whole bits R0 to R11 correspond to the respective bits of CPU addresses A5 to A16 and also the high order four bits C4 to C7 correspond to the respective bits of CPU addresses A17 to A20 respectively. |
