M16C User Manual.pdf

DMACMitsubishi microcomputersM16C / 62 GroupSINGLE-CHIP 16-BIT CMOS MICROCOMPUTERDMAi control registerb7 b6 b5 b4 b3 b2 b1 b0Symbol Address When resetDMiCON(i=0,1) 002C16, 003C16 00000X002Bit symbolDMBITDMASLDMASDMAEDSDDADBit nameTransfer unit bit select bitRepeat transfer modeselect bitDMA request bit (Note 1)DMA enable bitSource address directionselect bit (Note 3)Destination addressdirection select bit (Note 3)0 : 16 bits1 : 8 bitsFunction0 : Single transfer1 : Repeat transfer0 : DMA not requested1 : DMA requested0 : Disabled1 : Enabled0 : Fixed1 : Forward0 : Fixed1 : ForwardNothing is assigned.In an attempt to write to these bits, write “0”. The value, if read, turns out to be “0”.RW(Note 2)Note 1: DMA request can be cleared by resetting the bit.Note 2: This bit can only be set to “0”.Note 3: Source address direction select bit and destination address direction select bitcannot be set to “1” simultaneously.DMAi source pointer (i = 0, 1)(b23)b7(b19) (b16)(b15)(b8)b3 b0 b7 b0 b7 b0Symbol Address When resetSAR0 002216 to 002016 IndeterminateSAR1 003216 to 003016 IndeterminateTransfer countFunctionspecification• Source pointer0000016 to FFFFF16Stores the source addressNothing is assigned.In an attempt to write to these bits, write “0”. The value, if read, turns out to be “0”.RWDMAi destination pointer (i = 0, 1)(b23)b7(b19) (b16)(b15)(b8)b3 b0 b7 b0 b7 b0Symbol Address When resetDAR0 002616 to 002416 IndeterminateDAR1 003616 to 003416 IndeterminateFunctionTransfer countspecification• Destination pointer0000016 to FFFFF16Stores the destination addressNothing is assigned.In an attempt to write to these bits, write “0”. The value, if read, turns out to be “0”.RWDMAi transfer counter (i = 0, 1)(b15)(b8)b7 b0 b7 b0Symbol Address When resetTCR0 002916, 002816 IndeterminateTCR1 003916, 003816 IndeterminateFunction• Transfer counterSet a value one less than the transfer countTransfer countspecification000016 to FFFF16R WFigure 2.9.3. DMAC-related registers (2)419