| 摘要 |
<P>PROBLEM TO BE SOLVED: To smoothly switch transmission and reception operations even if a half-duplex card type memory having an input/output function for data is mounted on an electronic instrument having a full duplex driver resource. <P>SOLUTION: Firstly, transmission DMA (Direct Memory Access) controller initialization is applied to a transmission DMA controller 62; and reception DMA controller initialization is applied to a reception DMA controller 63. SD (Send Data) reception initialization is applied to an SD controller 60 to receive data from an SDIO (Send Data Input Output) card 80 to write the data into a memory 90. When a transmission and reception request from a system is changed, a selector 64 is switched by an SEL (Select) signal 65 from an SD access controller 61. SD transmission (or reception) initialization is applied to the SD controller 60; transmission processing (or reception processing) is then done. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
