Trigger Input; Power Output; Ground - Measurement Computing USB-1208HS-2AO User Manual

USB-1208HS-2AO User's Guide
Both the period and time delay ranges are 50 ns to 107.4 seconds.

Trigger input

The connection is an external digital trigger input. The trigger mode is software selectable for:
TRIG

Level-sensitive or edge-sensitive

Rising or falling edge

High or low level
The default setting at power up is edge sensitive, rising edge.
Retrigger
The acquisition uses the trigger settings for positive edge/negative edge and level-sensitive/edge-sensitive, but
automatically re-arms the trigger after it is activated

Power output

You can use the two
+5V
output up to 285 mA. Refer to Figure 3 and Figure 4 on page 10 for the location of this pin.
Caution! The
+5V
the USB-1208HS-2AO and possibly the computer.

Ground

The analog ground (
AGND
( ) connections provide a common ground for the digital I/O, timer/counter I/O, timer, clock I/O, and the
GND
+5 V terminals.
Figure 11. USB-1208HS-2AO PWM timer channel
connections to supply power to external devices or circuitry. These terminals can
terminals are outputs. Do not connect to an external power supply or you may damage
) connections provide a common ground for all analog I/O channels. The ground
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Functional Details