National Instruments 653X - Manual (Page 87)

Chapter 3 Timing Diagrams
653X User Manual 3-36 ni.com
Figure 3-33. Long Pulse Input State Machine
Wait
For
Space
Wait
For
REQ
Programmable
Delay
Programmable
Delay
Wait
For
REQ
When REQ
Asserted
When 6533 Device has
space for data, input data.*
Clear
ACK
Pulse
When REQ
Unasserted
Initial State: ACK Cleared
Send
ACK Pulse
* With REQ-edge latching enabled, the data input
is from the last active-going REQ edge.