External Clock I/O; Digital I/O - Measurement Computing USB-1208HS User Manual

USB-1208HS User's Guide
Figure 5 depicts a voltage source connected to a USB-1208HS configured for SE mode.
Figure 6 depicts a Wheatstone bridge signal source connected to a USB-1208HS configured for DIFF mode.
For more information on analog signal connections
For more information on single-ended inputs, refer to the Guide to DAQ Signal Connections (this document is
available on our web site at www.mccdaq.com/signals/signals.pdf).

External clock I/O

The USB-1208HS provides one external clock input (
inputs.
You can connect an external clock signal to

When using an external clock,

When using the internal clock,

Digital I/O

You can connect up to 16 digital I/O lines to screw terminals
The 16 DIO terminals have 47 kΩ resistors that you can configure for pull-up/pull-down using a jumper inside
the case. The default configuration is pull-down.
You can use the USB-1208HS digital I/O terminals to detect the state of any TTL-level input. Refer to the
schematic shown in Figure 7. If you set the switch to the +5 V input, DIO0 reads TRUE (1). If you move the
switch to GND, DIO0 reads FALSE (0).
Figure 5. Single-ended measurement connection
Figure 6. Differential measurement connection
AICKI
and/or
AICKI
AICKO outputs the pulse generated from
outputs the ADC scan clock.
AICKO
12
) and one external clock output (
.
AOCKI
AICKI .
through .
DIO0 DIO15
Functional Details
AICKO ) for analog