Figure 3-18. level ack output state machine – National Instruments 653X User Manual

Page 73

Chapter 3

Timing Diagrams

3-22

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Figure 3-18. Level ACK Output State Machine

Wait

For

Data

Wait

For

REQ

Programmable

Delay

Programmable

Delay

Wait

For

REQ

When REQ

Asserted

Clear ACK

When 6533 Device has data

to output, output data.*

When REQ

Unasserted

Initial State: ACK Cleared

Send

ACK

* With REQ-edge latching enabled, the data output is

delayed until the next inactive-going REQ edge.