USB-1808X User's Guide
Functional Details
12
4.
Hold both the top and bottom sections together, turn the device over and rest it on the surface, then
carefully remove the top section of the case to expose the circuit board.
Figure 6 shows the location of the
DIO
jumper on the circuit board.
Figure 6. Pull-up/down jumper location
5.
Configure the
DIO
jumper for pull-up or pull-down, as shown in Figure 7.
Figure 7. Pull-up/down jumper configuration
6.
Replace the top section of the housing and fasten it to the bottom section with the four screws.
For more information about digital signal connections
For general information about digital signal connections and digital I/O techniques, refer to the
Guide to DAQ
Signal Connections
www.mccdaq.com/support/DAQ-Signal-Connections.aspx
Counter input
Counter inputs can be read asynchronously under program control, or synchronously as part of a digital scan
group.
The
CTR0
and
CTR1
terminals are 32-bit general-purpose counters that can accept frequency inputs up to
50 MHz.
The USB-1808X supports the following counter input modes:
Totalize
Period measurement
Pulse-width measurement
Counter input modes are programmable with software. Each mode supports additional counter operation
options.
