| 摘要 |
PROBLEM TO BE SOLVED: To obtain a DMA controller for printer in which the order of data can be matched even if a user is unconscious of the type of printer control board or the type of data being transferred. SOLUTION: A CPU in an engine body reads out the value of a configuration register 328 in a printer control board and makes a decision which printer control board is inserted by that value. Based on the decision results, a data bus select register 310 is latched to Low or High so that the order of data is matched between the printer control board and the engine body thus selecting connection of the data bus between them. At the same time, connection of the data bus is altered depending on the type of data being transferred such that the order of data is matched between the printer control board and the engine body.
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