Gain Queue; Synchronizing Multiple Units - Measurement Computing USB-1608FS User Manual

USB-1608FS User's Guide

Gain queue

The USB-1608FS gain queue allows you to set up a different gain setting for each channel. The gain queue
removes the restriction of having a single gain for all channels. This feature creates a gain list which is written
to local memory on the USB-1608FS. The gain list is made up of a channel number and range setting. An
example of an eight-element list is shown in
Note that the gain queue must contain eight elements that include all eight channels. You must carefully match
the gain to the expected voltage range on the associated channel — otherwise, an over range condition can
occur. Although this condition does not damage the USB-1608FS, it does produce a useless full-scale reading.
It can also introduce a long recovery time due to saturation of the input channel.

Synchronizing multiple units

You can connect the SYNC pin of two USB-1608FS units together in a master/slave configuration and acquire
data synchronously from 16 channels. When the SYNC pin is configured as an output, the internal A/D pacer
clock signal is sent to the screw terminal. You can output the clock to the SYNC pin of a second USB-1608FS
configured for A/D pacer input.
You set the function of the SYNC pin (pin 36) for pacer input or pacer output by using Insta Cal. By default, the
SYNC pin is set for pacer input. To synchronize a master USB-1608FS with a slave USB-1608FS and acquire
data from 16 channels, follow the steps below:
1. Run Insta Cal.
2. Double-click on the USB-1608FS listing on the
dialog displays.
Configuration
3. Configure the SYNC pin of the master USB-1608FS for pacer output:
Double-click on the USB-1608FS that you want to configure as the master. The
o
dialog opens.
Click to select the
o
4. Configure the SYNC pin of the slave USB-1608FS for pacer input:
Double-click on the USB-1608FS that you want to configure as the slave. The
o
dialog displays.
Make sure that the
o
5. Connect the SYNC pin on the master USB-1608FS to the SYNC pin on the slave USB-1608FS.
Table 3-2
Table 3-2. Sample channel gain queue list
Element Channel
0 CH0
1 CH1
2 CH2
3 CH3
4 CH4
5 CH5
6 CH6
7 CH7
PC Board List
check box and then click
Enable Sync output
check box is not checked (unchecked is the default setting).
Enable Sync output
3-10
.
Range
BIP10V
BIP5V
BIP10V
BIP1V
BIP2V
BIP10V
BIP1V
BIP5V
on the
InstaCal
.
OK
Functional Details
main form. The
Board
Board Configuration
Board Configuration