Scanclk Signal; Extstrobe* Signal; Figure 4-14. Typical Pretriggered Acquisition; Figure 4-15. Scanclk Signal Timing - National Instruments AT-MIO/AI E Series User Manual

TRIG1
TRIG2
STARTSCAN
CONVERT*
Scan Counter
National Instruments Corporation
Don't Care
3 2 1

Figure 4-14. 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 4-15 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, software controls the level of the
0 2 2
t
d

Figure 4-15. SCANCLK Signal Timing

4-33
Chapter 4 Signal Connections
2 1 0
t
w
t
= 50 to 100 ns
d
t
= 400 to 500 ns
w
AT-MIO/AI E Series User Manual