Scanclk Signal; Extstrobe* Signal; Figure 4-12. Typical Pretriggered Acquisition; Figure 4-13. Scanclk Signal Timing - National Instruments VXI-MIO Series User Manual

Chapter 4 Signal Connections
TRIG1
TRIG2
STARTSCAN
CONVERT*
Scan Counter
VXI-MIO Series User Manual
Don't Care
3 2 1

Figure 4-12. Typical Pretriggered Acquisition

SCANCLK Signal

SCANCLK is an output-only signal that generates a pulse with the
leading edge occurring approximately 50 to 100 ns after an A/D
conversion begins. The polarity of this output is software selectable but
is typically configured so that a low-to-high leading edge can clock
external analog input multiplexers indicating when the input signal has
been sampled and can be removed. This signal has a 400 to 500 ns pulse
width and is software-enabled. Figure 4-13 shows the timing for the
SCANCLK signal.
CONVERT*
SCANCLK

EXTSTROBE* Signal

EXTSTROBE* is an output-only signal that generates either a single
pulse or a sequence of eight pulses in the hardware-strobe mode. An
external device can use this signal to latch signals or to trigger events.
In the single-pulse mode, your software controls the EXTSTROBE*
0 2 2
t
d

Figure 4-13. SCANCLK Signal Timing

4-26
2 1 0
t
w
t
= 50 to 100 ns
d
t
= 400 to 500 ns
w
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