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LED Definitions
The USB Module is equipped with a LED indicator to show
the current status of the device. When you plug the USB de-
vice into the USB port, the LED indicator will blink five times
and then stay lit to indicate that it is on. Please refer to the
following table for detailed LED indicator status information
LED Status
On
Off
Slow Blinking (5 times)
Fast Blinking
(Based on data transfer
speed).
Input Connections
Analog Input -
Single-ended Channel Connections
The single-ended input configuration has only one signal
wire for each channel, and the measured voltage (Vm) is
the voltage of the wire referred to the common ground.
Analog Input -
Differential Channel Connections
The differential input channels operate with two signal wires
for each channel, and the voltage difference between both
signal wires is measured. On USB-4716, when all channels
are configured to differential input, up to 8 analog channels
are available.
Description
Device ready for work
Device not ready to work
Device initialization
Device working
Input Connections (Cont.)
Analog Output Connections (Voltage)
USB-4716 provides two analog output channels, AO0 and
AO1. The figure below shows how to make analog output
connections on USB-4716.
Internal Pacer Trigger Connection
USB-4716 provides two 16-bit counters connected to a
10 MHz clock. Counter 0 is a counter that counts events
from an input channel. Counter 1 is a 16-bit timer for pacer
triggering. A low-to-high edge from the Counter 1 output will
trigger an A/D conversion on USB-4716.
External Trigger Source Connection
In addition to pacer triggering, USB-4716 also allows
external triggering for A/D conversions. When GATE is
connected to a +5V DC source, the external trigger function
is thereby disabled. And the external trigger function will be
enabled once the +5V DC source is removed.
External Trigger Source Connections
In addition to pacer triggering, the USB-4716 card also
allows external triggering for A/D conversions. A low-to-high
edge coming from EXT_TRG will trigger an A/D conversion
on the USB-4716 board.
Note!
Don't connect any signal to the EXT_TRG pin
when the external trigger function is not being
used.
Note!
If you use external triggering for A/D conversions,
we recommend you choose differential mode
for all analog input signals, so as to reduce the
cross-talk noise caused by the external trigger
source.
USB-4716 Startup Manual 3
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