Omega OM-USB-1208FS User Manual

Table of Contents

Preface

About this User's Guide ....................................................................................................................... 5

What you will learn from this user’s guide ......................................................................................................... 5

Conventions in this user’s guide ......................................................................................................................... 5

Where to find more information ......................................................................................................................... 5

Chapter 1

Introducing the OM-USB-1208FS ........................................................................................................ 6

OM-USB-1208FS block diagram ....................................................................................................................... 7

Software features ................................................................................................................................................ 7

Connecting a OM-USB-1208FS to your computer is easy ................................................................................. 8

Chapter 2

Installing the OM-USB-1208FS ............................................................................................................ 9

What comes with your OM-USB-1208FS shipment?......................................................................................... 9

Hardware .......................................................................................................................................................................... 9

Additional documentation ................................................................................................ ................................................. 9

Unpacking the OM-USB-1208FS ....................................................................................................................... 9

Installing the software ...................................................................................................................................... 10

Installing the hardware ..................................................................................................................................... 10

Chapter 3

Functional Details ............................................................................................................................... 11

Theory of operation - analog input acquisition modes ..................................................................................... 11

Software paced mode .......................................................................................................................................................11

Continuous scan mode .....................................................................................................................................................11

External components ........................................................................................................................................ 11

USB connector .................................................................................................................................................................12

LED .................................................................................................................................................................................12

Screw terminal wiring ......................................................................................................................................................12

Main connector and pin out .............................................................................................................................................13

Analog input terminals (CH0 IN - CH7 IN).....................................................................................................................13

Analog output terminals (D/A OUT 0 and D/A OUT 1) ..................................................................................................16

Digital I/O terminals (Port A0 to A7, and Port B0 to B7) ................................................................................................16

Power terminals ...............................................................................................................................................................16

Calibration terminal .........................................................................................................................................................17

Ground terminals .............................................................................................................................................................17

External trigger terminal ..................................................................................................................................................17

SYNC terminal ................................................................................................................................................................17

Counter terminal ..............................................................................................................................................................17

Accuracy ........................................................................................................................................................... 18

OM-USB-1208FS channel gain queue feature ................................................................................................. 20

Synchronizing multiple units ............................................................................................................................ 21

Chapter 4

Specifications ...................................................................................................................................... 22

Analog input ..................................................................................................................................................... 22

Analog output ................................................................................................................................................... 24

Digital input/output........................................................................................................................................... 24

External trigger ................................................................................................................................................. 25

External clock input/output............................................................................................................................... 25

Counter ............................................................................................................................................................. 25

Non-volatile memory ........................................................................................................................................ 26

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OM-USB-1208FS User's Guide

Microcontroller ................................................................................................................................................. 26

Power ................................................................................................................................ ................................ 26

General ............................................................................................................................................................. 27

Environmental .................................................................................................................................................. 27

Mechanical ....................................................................................................................................................... 27

Main connector and pin out .............................................................................................................................. 27

4-channel differential mode .............................................................................................................................................27

8-channel single-ended mode ...........................................................................................................................................28

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Preface

About this User's Guide

What you will learn from this user’s guide

This user’s guide explains how to install, configure, and use the OM-USB-1208FS so that you get the most out
of its USB data acquisition features.

This user’s guide also refers you to related documents available on our web site, and to technical support

resources.

Conventions in this user’s guide

For more information on …

Text presented in a box signifies additional information and helpful hints related to the subject matter you are
reading.

Caution! Shaded caution statements present information to help you avoid injuring yourself and others,

damaging your hardware, or losing your data.

< : > Angle brackets that enclose numbers separated by a colon signify a range of numbers, such as those assigned

to registers, bit settings, etc.

bold text Bold text is used for the names of objects on the screen, such as buttons, text boxes, and check boxes. For

example:

1. Insert the disk or CD and click the OK button.

italic text Italic text is used for the names of manuals and help topic titles, and to emphasize a word or phrase. For

example:
Never touch the exposed pins or circuit connections on the board.

Where to find more information

For additional information relevant to the operation of your hardware, refer to the Documents subdirectory
where you installed the software, or search for your device on our website at www.omega.com.

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Chapter 1

Introducing the OM-USB-1208FS

This user's guide contains all of the information you need to connect the OM-USB-1208FS to your computer
and to the signals you want to measure.

The OM-USB-1208FS is a USB 2.0 full-speed device supported under popular Microsoft® Windows® operating
systems. It is designed for USB 1.1 ports, and was tested for full compatibility with both USB 1.1 and USB 2.0
ports.

The OM-USB-1208FS features eight analog inputs, two 12-bit analog outputs, 16 digital I/O connections, and
one 32-bit external event counter. The OM-USB-1208FS is powered by the +5 volt USB supply from your
computer. No external power is required.

The analog inputs are software configurable for either eight 11-bit single-ended inputs, or four 12-bit
differential inputs. Sixteen digital I/O lines are independently selectable as input or output in two 8-bit ports.

A 32-bit counter can count TTL pulses. The counter increments when the TTL levels transition from low to
high (rising-edge).

A SYNC (synchronization) input / output line lets you pace the analog input acquisition of one USB module
from the clock output of another.

The OM-USB-1208FS is shown in Figure 1. I/O connections are made to the screw terminals located along
each side of the OM-USB-1208FS.

Figure 1. OM-USB-1208FS

6

OM-USB-1208FS User's Guide Introducing the OM-USB-1208FS

OM-USB-1208FS block diagram

OM-USB-1208FS functions are illustrated in the block diagram shown here.

Figure 2. OM-USB-1208FS functional block diagram

Software features

For information on the features of InstaCal and the other software included with your OM-USB-1208FS, refer
to the OMB-DAQ-2416 Series and OM-USB Series Data Acquisition Software User’s Guide that shipped with
your device.

7

OM-USB-1208FS User's Guide Introducing the OM-USB-1208FS

Connecting a OM-USB-1208FS to your computer is easy

Installing a data acquisition device has never been easier.
 The OM-USB-1208FS relies upon the Microsoft Human Interface Device (HID) class drivers. The HID

class drivers ship with every copy of Windows that is designed to work with USB ports. We use the
Microsoft HID because it is a standard, and its performance delivers full control and maximizes data
transfer rates for your OM-USB-1208FS. No third-party device driver is required.

 The OM-USB-1208FS is plug-and-play. There are no jumpers to position, DIP switches to set, or interrupts

to configure.

 You can connect the OM-USB-1208FS before or after you install the software, and without powering down

your computer first. When you connect an HID to your system, your computer automatically detects it and
configures the necessary software. You can connect and power multiple HID peripherals to your system
using a USB hub.

You can run up to two OM-USB-1208FS units on most computers.

 You can connect your system to various devices using a standard four-wire cable. The USB connector

replaces the serial and parallel port connectors with one standardized plug and port combination.

 You do not need a separate power supply module. The USB automatically delivers the electrical power

required by each peripheral connected to your system.

 Data can flow two ways between a computer and peripheral over USB connections.

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Installing the OM-USB-1208FS

What comes with your OM-USB-1208FS shipment?

As you unpack your OM-USB-1208FS, verify that the following components are included.

Hardware

 OM-USB-1208FS (shown with cable)

Chapter 2

 USB cable (2 meter length)

Additional documentation

In addition to this hardware user's guide, you should also receive the OMB-DAQ-2416 Series and OM-USB
Series Data Acquisition Software User’s Guide. This booklet supplies a brief description of the software you

received with your OM-USB-1208FS and information regarding installation of that software. Please read this
booklet completely before installing any software or hardware.

Unpacking the OM-USB-1208FS

As with any electronic device, you should take care while handling to avoid damage from static
electricity. Before removing the OM-USB-1208FS from its packaging, ground yourself using a wrist strap or by
simply touching the computer chassis or other grounded object to eliminate any stored static charge.

If any components are missing or damaged, notify Omega Engineering immediately by phone, fax, or e-mail.

 Phone: [phone]
 Fax: [phone]
 Email: [e-mail]

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