RX610 Group
12. DMA Controller (DMAC)
R01UH0032EJ0120 Rev.1.20
Page 331 of 1006
Feb 20, 2013
12.3.10
Rotate
When "rotate" is selected with the DMOD[2:0] and SMOD[2:0] bits in DMMOD of DMACm, transfer destination and
source addresses are automatically increased during data transfer. The values written at the beginning of DMA transfer
are reloaded to the address registers when single-operand transfer is completed.
Figure 12.7 shows an example of "rotate" transfer.
Block 2
8 data
(32 bytes)
Block 3
8 data
(32 bytes)
8 data
(32 bytes)
Block 1
8 data
(32 bytes)
Transfer byte count
(96 bytes)
Start address
This figure shows DMA transfer under the following conditions.
• DMACm.DMMOD DMOD[2:0] bits = 001b (plus)
DMACm.DMMOD.SMOD[2 0] bits = 011b (rotate)
DMACm.DMMOD.SZSEL[2:0] bits = 010b (32 bits)
DMACm.DMMOD.OPSEL[3:0] bits = 0011b (8 data)
• DMACm.DMCBC register = 00000060h (96 bytes)
Start address
1 operand
1 operand
1 operand
Transfer source
(rotate)
Transfer destination
(plus)
Figure 12.7
Example of "Rotate" Transfer
12.4
Interrupts
When the DINTMm bit (m = 0 to 3) in DMICNT is set to 1 (DMAm interrupts enabled), a DMAm interrupt request
(DMTENDm) is generated upon completion of channel-m DMA transfer. Figure 12.8 shows the schematic logic diagram
of interrupt outputs.
To use a DMAm interrupt, write 1 to the DEDETm flag in DMEDET of a channel in which a DMA interrupt request is
generated in the interrupt routine. Setting the DINTMm bit in DMICNT to 1 from 0 while the DEDETm flag in
DMEDET is set to 1 generates a DMAm interrupt request (DMTENDm) regardless of the DMAC transfer status.
The interrupt control unit (ICU) can be set to select a DMAm interrupt as a source for activation of the data transfer
controller (DTC). For details, refer to section 10, Interrupt Control Unit (ICU).
DMEDET.DEDETm
When the specified number of data
transfer operations are completed
DMICNT.DINTMm
1-setting condition
Interrupt output logic diagram for DMAC channel m
(DMACm)
m = 0 to 3
DMAm interrupt request
(DMTENDm)
Figure 12.8 Schematic Logic Diagram of Interrupt Outputs
Summary of Contents for RX600 Series
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