National Instruments DIO 6533 - Manual (Page 83)

Chapter 5 Signal Timing
DIO 6533 User Manual 5-24 © National Instruments Corporation
Figure 5-20 shows an input transfer in trailing-edge mode.
Figure 5-20. Trailing-Edge Mode Input
Wait
For
Space
Wait
For
REQ
Programmable
Delay
Programmable
Delay
Wait
For
REQ
When REQ
Unasserted
When 6533 Device
Has Space For Data,
Input Data*
Clear
ACK
When REQ
Asserted
Send
ACK
Initial State
ACK Cleared
* With REQ-edge latching enabled, the data read
is from the last inactive-going REQ edge.