National Instruments 653 Series User Manual page 61

Chapter 3 Timing Diagrams
PCLK
ACK
REQ
Data In
Valid
PCLK
ACK
REQ
Data Out
Valid
Note Data is transferred only when both the NI 653X and the peripheral device are ready
(and thus ACK and REQ are asserted), so it is not reasonable to expect data to arrive at
consistent intervals. If consistent intervals are an important criteria for your application,
use pattern I/O.
NI 653X User Manual
D1 D2
Figure 3-3. Burst Transfer Example (Input)
D1 D2
Figure 3-4. Burst Transfer Example (Output)
3-6
D3 D4
= Data Transfer Occurs
D3 D4
= Data Transfer Occurs
D5
D5
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