National Instruments 653X Manuale Utente

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Chapter 3
Timing Diagrams
© National Instruments Corporation
3-11
Figure 3-8.  Burst Output Timing Diagram (PCLK Reversed)
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
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
t
pdo
PCLK to output data valid
28
t
doh
Hold time from PCLK to output data 
invalid
4
t
dis
Setup time from input data valid to PCLK
0
t
dih
Hold time from PCLK to input data invalid
0
1
t
pc
 = programmable delay from 100 to 700 ns, or 50 ns if programmable delay is 0. Timebase stability for the board 
20 MHz clock source is 50 ppm.
All timing values are in nanoseconds.
PCLK
ACK
Data Out Valid
REQ
t
rs
t
pa
t
pdo
t
pw
t
pc
t
doh
t
rh
t
ah