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Section 7 DMA Controller (DMAC)
Rev. 3.00 Mar. 14, 2006 Page 135 of 804
REJ09B0104-0300
A block diagram of the DMAC is shown in figure 7.1.
External pins
DREQn
*
DACKn
*
TENDn
*
Interrupt signals
requested to the
CPU by each
channel
Internal activation sources
Internal activation
source detector
Controller
DMDR_n
DMRSR_n
DACR_n
DOFR_n
Internal address bus
Internal data bus
DSAR_n
DDAR_n
DTCR_n
DBSR_n
Module data bus
Address buffer
Data buffer
Operation unit
Operation unit
...
[Legend]
DSAR_n: DMA source address register
DREQn
: DMA transfer request
DDAR_n: DMA destination address register
DACKn
: DMA transfer acknowledge
DOFR_n: DMA offset register
TENDn
: DMA transfer end
DTCR_n: DMA transfer count register
n = 0 to 3
DBSR_n: DMA block size register
DMDR_n: DMA mode control register
DACR_n: DMA address control register
DMRSR_n:
DMA module request select register
Note:
*
Auto request activation and single address mode are not supported by the
H8SX/1520
Group.
Figure 7.1 Block Diagram of DMAC
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