Datasheet

8.0 Device Characteristics (Continued)
57
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USBN9603/USBN9604
8.6 DMA SUPPORT TIMING
(3.0V< V
CC
< 5.5V, 0˚C < TA< +70˚C, unless otherwise specified)
.
Figure 29. DMA Write to USBN9603/4
.
Figure 30. DMA Read from USBN9603/4
Symbol Parameter Conditions Min Typ Max Units
t
RHAL
Request High to ACK Low
C
L
=50pF 0 nS
t
ALWL
ACK Low to Write Low
C
L
=50pF 0 nS
t
WW
Write Pulse Width
C
L
=50pF 1/CKI nS
t
WRL
1
1. The minimum value of this parameter is from the system perspective. This value can be used
as the maximum value from the device perspective.
The maximun value of this parameter is infinity.
Write High to Request Low
C
L
=50pF 2/MCLK nS
t
DWR
1
DMA Write Recovery
2
2. If DMA transfer is not interrupted by read or write. If the transfer is interrupted, two additional
MCLK cycles are used.
C
L
=50pF 2/MCLK nS
t
ALRL
ACK low to Read Low
C
L
=50pF 0 nS
t
RW
Read Pulse Width
C
L
=50pF 1/CKI nS
t
RRL
1
Read High to Request Low
C
L
=50pF 2/MCLK nS
t
DRR
1
DMA Read Recovery
2
C
L
=50pF 2/MCLK nS
DACK
DRQ
D7-0
WR
Input
t
ALWL
t
RHAL
t
WW
t
WRL
t
DWR
DACK
DRQ
D7-0
RD
Output
t
ALRL
t
RHAL
t
RW
t
RRL
t
DRR
Obsolete