National Instruments DAQCard-6533 User Manual page 74

Chapter 3 Timing Diagrams
Initial State: ACK Cleared
When REQ
Asserted
Wait
For
REQ
Clear ACK
When REQ
Unasserted
NI 653X User Manual
Programmable
Delay
Send
ACK
Wait
For
REQ
Figure 3-15. Level-ACK Input State Machine
3-18
Wait
For
Space
When 6533 Device has space
for data, input data.*
Programmable
Delay
* With REQ-edge latching enabled, the data input
is from the last active-going REQ edge.
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