National Instruments 3.21E+04 Benutzerhandbuch
Chapter 4 Signal Connections
AT-MIO/AI E Series User Manual
4-44
National Instruments Corporation
Figures 4-28 and 4-29
show the input and output timing requirements
for the UPDATE* signal.
Figure 4-28. UPDATE* Input Signal Timing
Figure 4-29. UPDATE* Output Signal Timing
The DACs are updated within 100 ns of the leading edge. Separate the
UPDATE* pulses with enough time that new data can be written to the
DAC latches.
UPDATE* pulses with enough time that new data can be written to the
DAC latches.
The AT E Series board UI counter normally generates the UPDATE*
signal unless you select some external source. The UI counter is started
by the WFTRIG signal and can be stopped by software or the internal
Buffer Counter.
signal unless you select some external source. The UI counter is started
by the WFTRIG signal and can be stopped by software or the internal
Buffer Counter.
D/A conversions generated by either an internal or external UPDATE*
signal do not occur when gated by the software command register gate.
signal do not occur when gated by the software command register gate.
Rising-edge
polarity
polarity
Falling-edge
polarity
polarity
t
w
t
w
= 10 ns minimum
t
w
t
w
= 300-350 ns