National Instruments 653X User Manual page 74

ACK
REQ
Output Data Valid
(REQ-edge
latching)
Output Data Valid
(REQ-edge
latching disabled)
Parameter
Input Parameters
t
REQ pulse width
rr*
t
REQ inactive duration
r*r
t
ACK to next REQ
ar
Output Parameters
t
ACK pulse width
aa*
t
REQ to ACK inactive
ra*
t REQ inactive to new output data
r*do
(with REQ-edge latching)
t
REQ to new output data
rdo
(with REQ-edge latching disabled)
t
Output data valid to ACK
doa
(with REQ-edge latching disabled)
t
1
(min.) = 25 + programmable delay
doa
Note With REQ edge latching disabled (default), output data valid will hold t
the REQ edge is asserted. With REQ edge latching enabled, that data will be held for at
most t ns after the REQ edge deasserts.
rdo
© National Instruments Corporation
t
aa*
t
ar
t
r*r
t
ra*
t
doa
Description
Figure 3-19. Level ACK Output Timing Diagram
3-23
Chapter 3
t
rr*
t
r*do
t
rdo
ACK and REQ are shown as active high
Minimum
75
75
0
225
100
0
0
1
25
Timing Diagrams
Maximum
—
—
—
—
200
50
—
—
ns after
rdo
653X User Manual