Renesas SH7641 - Manual (Page 491)

Section 13 Direct Memory Access Controller (DMAC)
Rev. 4.00 Sep. 14, 2005 Page 441 of 982
REJ09B0023-0400
CKIO
1st acceptance 2nd acceptance
Acceptance start
Bus cycle
DREQ
(Rising)
DACK
(Active-high)
CPU CPU CPU DMAC
Non sensitive period
Figure 13.13 Example of
DREQ Input Detection in Cycle Steal Mode Edge Detection
CKIO
Bus cycle
Bus cycle
DREQ
(Rising)
DACK
(Active-high)
DREQ
(Overrun 1 at
high level)
DACK
(Active-high)
CPU CPU CPU DMAC
CKIO
CPU CPU CPU DMAC
1st acceptance 2nd acceptance
1st acceptance 2nd acceptance
Acceptance
start
Acceptance
start
Non sensitive period
Non sensitive period
Figure 13.14 Example of
DREQ Input Detection in Cycle Steal Mode Level Detection
CKIO
DREQ
DACK
CPU CPU DMAC DMAC Bus cycle
Non sensitive period
Burst acceptance
Figure 13.15 Example of
DREQ Input Detection in Burst Mode Edge Detection