HD6417751RBP240V Datasheet, PDF (685/1226 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

14. Direct Memory Access Controller (DMAC)
Table 14.13 DMAC Pins in DDT Mode
Pin Name
Data bus request
Data bus available
Abbreviation
DBREQ
(DREQ0)
BAVL/ID2
(DRAK0)
Transfer request signal TR
(DREQ1)
DMAC strobe
Channel number
notification
TDACK
(DACK0)
ID[1:0]
(DRAK1, DACK1)
I/O
Input
Output
Input
Output
Output
Function
Data bus release request from external
device for DTR format input
Data bus release notification
Data bus can be used 2 cycles after
BAVL is asserted
Notification of channel number to
external device at same time as TDACK
output
If asserted 2 cycles after BAVL
assertion, DTR format is sent
Only TR asserted: DMA request
DBREQ and TR asserted
simultaneously: Direct request to
channel 2
Reply strobe signal for external device
from DMAC
Notification of channel number to
external device at same time as TDACK
output
(ID [1] = DRAK1, ID [0] = DACK1)
Requests for DMA transfer from external devices are normally accepted only on channel 0
(DREQ0) and channel 1 (DREQ1). In DDT mode, the BAVL pin functions as both the data-bus-
available pin and channel-number-notification (ID2) pin.
14.6.3 Register Configuration (SH7751R)
Table 14.14 shows the configuration of the DMAC's registers. The DMAC of the SH7751R has a
total of 33 registers: four registers are assigned to each channel, and there is a control register for
the overall control of the DMAC.
Rev.4.00 Oct. 10, 2008 Page 585 of 1122
REJ09B0370-0400