National Instruments 653X Manuale Utente
Chapter 3
Timing Diagrams
3-8
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Figure 3-5. Burst Input Timing Diagram (Default)
Parameter
Description
Minimum
Maximum
Input Parameters
t
rs
Setup time from REQ valid to PCLK
12
—
t
rh
Hold time from PCLK to REQ invalid
0
—
t
dis
Setup time from input data valid to PCLK
4
—
t
dih
Hold time from PCLK to input data invalid
6
—
Output Parameters
t
pc
PCLK cycle time
50
700
1
t
pw
PCLK high pulse duration
t
pc
/2 – 5
t
pc
/2 + 5
t
pa
PCLK to ACK valid
—
18
t
ah
Hold time from PCLK to ACK invalid
3
—
1
t
pc
= programmable delay from 100 to 700 ns, or 50 ns if programmable delay is 0. Timebase stability for the onboard
20 MHz clock source is 100 ppm.
All timing values are in nanoseconds.
PCLK
ACK
Data In Valid
REQ
t
dis
t
dih
t
rs
t
pa
t
pw
t
pc
t
rh
t
ah