M16C User Manual.pdf

DMACMitsubishi microcomputersM16C / 62 GroupSINGLE-CHIP 16-BIT CMOS MICROCOMPUTER(7) Switching function(a) Switching between one-shot transfer and repeated transfer'One-shot transfer' refers to a mode in which DMA is disabled after the transfer counter underflows.'Repeated transfer' refers to a mode in which a reload is carried out after the transfer counter underflows.The reload is carried out for the transfer counter and on the address pointer subjected toforward direction.The following are examples of operation in which the options listed are selected.• A fixed address from an arbitrary 1M byte space, one-shot transfer ........................................ P420• An arbitrary 1M byte space from a fixed address, repeated transfer........................................ P422(8) Registers related to DMACFigure 2.9.1 shows the memory map of DMAC-related registers, and Figures 2.9.2 and 2.9.3 showDMAC-related registers.002016002116002216002316002416002516002616002716002816002916DMA0 source pointer (SAR0)DMA0 destination pointer (DAR0)DMA0 transfer counter (TCR0)002C15DMA0 control register (DM0CON)003016003116003216003316003416003516003616003716003816003916DMA1 source pointer (SAR1)DMA1 destination pointer (DAR1)DMA1 transfer counter (TCR1)003C16DMA1 control register (DM1CON)004B16004C16DMA0 interrupt control register (DM0IC)DMA1 interrupt control register (DM1IC)03B81603B91603BA16DMA0 cause select register (DM0SL)DMA1 cause select register (DM1SL)Figure 2.9.1. Memory map of DMAC-related registers417