Renesas SH7781 - Manual (Page 697)

14. Direct Memory Access Controller (DMAC)
Rev.1.00 Jan. 10, 2008 Page 667 of 1658
REJ09B0261-0100
14.2 Input/Output Pins
The DMAC-related external pins are shown below.
Table 14.1 shows the configuration of the pins that are connected to external device. The DMAC
has pins for four channels (channels 0 to 3) used in the external bus.
Table 14.1 Pin Configuration for the External Bus
Channel Function Pin Name I/O Description
0 DMA transfer request
DREQ0* 1 Input DMA transfer request input from external
device to channel 0
DREQ0 acceptance
confirmation
DRAK0* 2 Output Notifies acceptance of DMA transfer
request and start of execution from
channel 0 to external device
DMA transfer end
notification
DACK0* 2 Output Outputs strobe to DMA transfer request
from channel 0 to external device
1 DMA transfer request
DREQ1* 1 Input DMA transfer request input from external
device to channel 1
DREQ1 acceptance
confirmation
DRAK1* 2 Output Notifies acceptance of DMA transfer
request and start of execution from
channel 1 to external device
DMA transfer end
notification
DACK1* 2 Output Outputs strobe to DMA transfer request
from channel 1 to external device
2 DMA transfer request
DREQ2* 1 Input DMA transfer request input from external
device to channel 2
DREQ2 acceptance
confirmation
DRAK2* 2 Output Notifies acceptance of DMA transfer
request and start of execution from
channel 2 to external device
DMA transfer end
notification
DACK2* 2 Output Outputs strobe to DMA transfer request
from channel 2 to external device
3 DMA transfer request
DREQ3* 1 Input DMA transfer request input from external
device to channel 3
DREQ3 acceptance
confirmation
DRAK3* 2 Output Notifies acceptance of DMA transfer
request and start of execution from
channel 3 to external device.
DMA transfer end
notification
DACK3* 2 Output Outputs strobe to DMA transfer request
from channel 3 to external device
Notes: 1. The initial value is low-level detection.
2. The initial value is low-active.