Meilhaus RedLab 1608FS User manual

RedLab 1608FS
USB-based
Analog and Digital I/O Module
User's Guide
Document Revision 1.4 E, January, 2008
© Copyright 2008, Meilhaus Electronic™

3
Imprint
User’s Guide RedLab® Series
Document Revision 1.4 E
Revision Date: January 2008
Meilhaus Electronic GmbH
Fischerstraße 2
D-82178 Puchheim near Munich, Germany
http://www.meilhaus.de
© Copyright 2008 Meilhaus Electronic GmbH
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or
transmitted, in any form by any means, electronic, mechanical, by photocopying, recording, or
otherwise without the prior written permission of Meilhaus Electronic GmbH.
Important note:
All the information included in this user’s gide were put together with utmost care and to best
knowledge. However, mistakes may not have been erased completely.
For this reason, the firm Meilhaus Electronic GmbH feels obliged to point out that they cannot be take
on neither any warranty (apart from the claims for warranty as agreed) nor legal responsibility or
liability for consequences caused by incorrect instructions.
We would appreciate it if you inform us about any possible mistakes.
The trademark Personal Measurement Device, TracerDAQ, Universal Library, InstaCal, Harsh
Environment Warranty, Measurement Computing Corporation, and the Measurement Computing logo
are either trademarks or registered trademarks of Measurement Computing Corporation.
Windows, Microsoft, and Visual Studio are either trademarks or registered trademarks of Microsoft
Corporation.
LabVIEW is a trademark of National Instruments.
CompactFlash is a registered trademark of SanDisk Corporation.
XBee is a trademark of MaxStream, Inc.
All other trademarks are the property of their respective owners.

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Table of Contents
Preface
About this User's Guide .......................................................................................................................6
What you will learn from this user's guide .........................................................................................................6
Conventions in this user's guide .........................................................................................................................6
Where to find more information .........................................................................................................................6
Chapter 1
Introducing the RedLab 1608FS ..........................................................................................................7
RedLab 1608FS block diagram ..........................................................................................................................8
Software features ................................................................................................................................................8
Connecting a RedLab 1608FS to your computer is easy....................................................................................9
Chapter 2
Installing the RedLab 1608FS ............................................................................................................10
What comes with your RedLab 1608FS shipment?..........................................................................................10
Hardware .........................................................................................................................................................................10
Additional documentation................................................................................................................................................10
Unpacking the RedLab 1608FS........................................................................................................................11
Installing the software ......................................................................................................................................11
Installing the hardware .....................................................................................................................................11
Chapter 3
Functional Details ...............................................................................................................................13
Theory of operation - analog input acquisition modes .....................................................................................13
Software paced mode.......................................................................................................................................................13
Continuous scan mode .....................................................................................................................................................13
Burst scan mode...............................................................................................................................................................13
External components ........................................................................................................................................14
USB connector.................................................................................................................................................................14
LED .................................................................................................................................................................................14
Screw terminal wiring......................................................................................................................................................15
Main connector and pin out .............................................................................................................................................16
Analog input terminals (CH0 IN - CH7 IN).....................................................................................................................16
Digital I/O terminals (DIO0 to DIO7)..............................................................................................................................17
Power terminals ...............................................................................................................................................................18
Ground terminals .............................................................................................................................................................18
Calibration terminal .........................................................................................................................................................19
Counter terminal ..............................................................................................................................................................19
SYNC terminal ................................................................................................................................................................19
Trigger terminal ...............................................................................................................................................................19
Accuracy...........................................................................................................................................................19
Gain queue........................................................................................................................................................22
Synchronizing multiple units............................................................................................................................23
Chapter 4
Specifications......................................................................................................................................24
Analog input section.........................................................................................................................................24
Digital input/output...........................................................................................................................................25
External trigger.................................................................................................................................................26
External clock input/output...............................................................................................................................26
Counter section.................................................................................................................................................27
Memory ............................................................................................................................................................27
Microcontroller.................................................................................................................................................27

RedLab 1608FS User's Guide
5
Power................................................................................................................................................................27
General .............................................................................................................................................................28
Environmental ..................................................................................................................................................28
Mechanical .......................................................................................................................................................28
Main connector and pin out ..............................................................................................................................28

6
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 RedLab 1608FS 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:
The InstaCal installation procedure is explained in the Quick Start Guide.
Never touch the exposed pins or circuit connections on the board.
Where to find more information
The following electronic documents provide helpful information relevant to the operation of the RedLab
1608FS.
The Quick Start Guide is available on our RedLab CD in the root directory.
The Guide to Signal Connections is available on our RedLab CD under „ICalUL\Documents“.
The Universal Library User's Guide is available on our RedLab CD under „ICalUL\Documents“.
The Universal Library Function Reference is available on our RedLab CD under „ICalUL\Documents“.
The Universal Library for LabVIEW™User’s Guide is available on our RedLab CD under
„ICalUL\Documents“.

7
Chapter 1
Introducing the RedLab 1608FS
This user's guide contains all of the information you need to connect the RedLab 1608FS to your computer and
to the signals you want to measure. The RedLab 1608FS is part of the Meilhaus Electronic brand of USB-based
data acquisition products.
The RedLab 1608FS 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 RedLab 1608FS offers true simultaneous sampling of up to eight channels of 16-bit single-ended analog
input. This is accomplished through the use of one A/D converter per channel. The range of each channel is
independently configurable via software. Eight digital IO lines are independently selectable as input or output.
A 32-bit counter is capable of counting TTL pulses. The RedLab 1608FS is powered by the +5 volt USB supply
from your computer. No external power is required.
A SYNC (synchronization) control line allows you to synchronize two RedLab 1608FS modules together to
acquire data synchronously from 16 analog inputs.
The RedLab 1608FS is shown in Figure 1. I/O connections are made to the screw terminals located along each
side of the RedLab 1608FS.
Figure 1. RedLab 1608FS

RedLab 1608FS User's Guide Introducing the RedLab 1608FS
8
RedLab 1608FS block diagram
RedLab 1608FS functions are illustrated in the block diagram shown here.
Screw terminal I/O connector
SPI
8
DIO
G= 1, 2, 5, 10
A
/D 0
A
/D 1
A
/D 2
A
/D 3
A
/D 4
A
/D 5
A
/D 6
A
/D 7
32-bit
Event Counter
1 channel
USB
Microcontroller
SYNC
16
32k x 16
SRAM
USB
Full-speed
USB 2.0
Compliant
Interface
1616
Screw terminal I/O connector
CAL
TRIG_IN
CAL
Figure 2. RedLab 1608FS Functional Block Diagram
Software features
For information on the features of InstaCal and the other software included with your RedLab 1608FS, refer to
the Quick Start Guide that shipped with your device. The Quick Start Guide is also available in PDF on our
RedLab CD (root directory).

RedLab 1608FS User's Guide Introducing the RedLab 1608FS
9
Connecting a RedLab 1608FS to your computer is easy
Installing a data acquisition device has never been easier.
The RedLab 1608FS 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 RedLab 1608FS. No third-party device driver is required.
The RedLab 1608FS is plug-and-play. There are no jumpers to position, DIP switches to set, or interrupts
to configure.
You can connect the RedLab 1608FS 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 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.

10
Chapter 2
Installing the RedLab 1608FS
What comes with your RedLab 1608FS shipment?
The following items are shipped with the RedLab 1608FS.
Hardware
RedLab 1608FS
USB cable (2 meter length)
Additional documentation
In addition to this hardware user's guide, you should also receive the Quick Start Guide (available on our
RedLab CD (root directory)). This booklet supplies a brief description of the software you received with your
RedLab 1608FS and information regarding installation of that software. Please read this booklet completely
before installing any software or hardware.

RedLab 1608FS User's Guide Installing the RedLab 1608FS
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Unpacking the RedLab 1608FS
As with any electronic device, you should take care while handling to avoid damage from static
electricity. Before removing the RedLab 1608FS 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 your RedLab 1608FS is damaged, notify Meilhaus Electronic immediately by phone, fax, or e-mail. For
international customers, contact your local distributor where you purchased the RedLab 1608FS.
Phone: [phone]
Fax: [phone]
E-Mail: [email protected]
Installing the software
Refer to the Quick Start Guide for instructions on installing the software Guide (available on our RedLab CD
(root directory)).
Installing the hardware
Be sure you are using the latest system software
Before you connect the RedLab 1608FS, make sure that you are using the latest versions of the USB drivers.
Before installing the RedLab 1608FS, download and install the latest Microsoft Windows updates. In particular,
when using Windows XP, make sure you have XP Hotfix KB822603 installed. This update is intended to
address a serious error in Usbport.sys when you operate a USB device. You can run Windows Update or
download the update from www.microsoft.com/downloads/details.aspx?familyid=733dd867-56a0-4956-b7fe-
e85b688b7f86&displaylang=en. For more information, refer to the Microsoft Knowledge Base article
"Availability of the Windows XP SP1 USB 1.1and 2.0update." This article is available at
support.microsoft.com/?kbid=822603.
To connect the RedLab 1608FS to your system, turn your computer on, and connect the USB cable to a USB
port on your computer or to an external USB hub that is connected to your computer. The USB cable provides
power and communication to the RedLab 1608FS.
The RedLab 1608FS installs as a composite device with separate devices attached. When you connect the
RedLab 1608FS for the first time, Found New Hardware popup balloons (Windows XP) or dialogs (other
Windows version) open as each RedLab 1608FS interface is detected.
It is normal for multiple dialogs to open when you connect the RedLab 1608FS for the first time. For additional
information, refer to the "Notes on installing and using the RedLab 1608FS" that was shipped with the RedLab
1608FS.

RedLab 1608FS User's Guide Installing the RedLab 1608FS
12
When the last balloon or dialog closes, the installation is complete. The LED on the RedLab 1608FS should
flash and then remain lit. This indicates that communication is established between the RedLab 1608FS and
your computer.
Caution! Do not disconnect any device from the USB bus while the computer is communicating with the
RedLab 1608FS, or you may lose data and/or your ability to communicate with the RedLab 1608FS.
If the LED turns off
If the LED is lit but then turns off, the computer has lost communication with the RedLab 1608FS. To restore
communication, disconnect the USB cable from the computer, and then reconnect it. This should restore
communication, and the LED should turn back on.

13
Chapter 3
Functional Details
Theory of operation - analog input acquisition modes
The RedLab 1608FS can acquire analog input data in three basic modes – software paced, continuous scan, and
burst scan.
Software paced mode
You can acquire one analog sample at a time in software paced mode. You initiate the A/D conversion by
calling a software command. The analog value is converted to digital data and returned to the computer. You
can repeat this procedure until you have the total number of samples that you want from one channel.
The maximum throughput sample rate in software paced mode is system-dependent.
Continuous scan mode
You can acquire data from up to eight channels simultaneously in continuous scan mode. The analog data is
continuously acquired, converted to digital values, and written to an on-board FIFO buffer on the RedLab
1608FS until you stop the scan. The FIFO buffer is serviced in blocks as the data is transferred from the RedLab
1608FS FIFO buffer to the memory buffer on your computer.
The maximum sampling rate is an aggregate rate, where the total sample rate for all channels is 100 kS/s
divided by the number of channels, with a maximum rate of 50 kS/s for any channel. Using this equation, you
can acquire data with the RedLab 1608FS from one channel at 50 kS/s, two channels at 50 kS/s each, four
channels at 25 kS/s each, and so on, up to eight channels at 12.5 kS/s each. You can start a continuous scan with
either a software command or with an external hardware trigger event.
Burst scan mode
In burst scan mode, you can acquire data with the RedLab 1608FS using the full capacity of its 32 K sample
FIFO. The acquired data is then read from the FIFO and transferred to a user buffer in your computer. You can
initiate a single acquisition sequence of one, two, four, or eight channels by either a software command or an
external hardware trigger.
Burst scans are limited to the depth of the on-board memory, as the data is acquired at a rate faster than it can be
transferred to the computer. The maximum sampling rate is an aggregate rate, where the total acquisition rate
for all channels is 200 kS/s divided by the number of channels, with a maximum rate of 50 kS/s for any channel.
The maximum rate that you can acquire data using burst scan mode is 50 kS/s each for one, two, or four
channels, and 25 kS/s each for eight channels.

RedLab 1608FS User's Guide Functional Details
14
External components
The RedLab 1608FS has the following external components, as shown in Figure 3.
USB connector
LED
Screw terminal banks (2)
Figure 3. RedLab 1608FS
USB connector
The USB connector is on the right side of the RedLab 1608FS. This connector provides +5 V power and
communication. The voltage supplied through the USB connector is system-dependent, and may be less than 5
V. No external power supply is required.
LED
The LED on the front of the RedLab 1608FS indicates the communication status. It uses up to 5 mA of current
and cannot be disabled. The table below explains the function of the RedLab 1608FS LED.
LED Illumination
When the LED is… It indicates…
Steady green The RedLab 1608FS is connected to a computer or external USB hub.
Blinks continuously Data is being transferred.
Blinks three times Initial communication is established between the RedLab 1608FS and the computer.
Blinks at a slow rate The analog input is configured for external trigger. The LED stops blinking and illuminates
steady green when the trigger is received.
USB connector / cable
Screw terminal
Pins 21 to 40
Screw terminal
Pins 1 to 20
LED

RedLab 1608FS User's Guide Functional Details
15
Screw terminal wiring
The RedLab 1608FS has two rows of screw terminals—one row on the top edge of the housing, and one row on
the bottom edge. Each row has 20 connections. Pin numbers are identified in Figure 4.
Figure 4. RedLab 1608FS screw terminal pin numbers
Screw terminal – pins 1-20
The screw terminals on the top edge of the RedLab 1608FS (pins 1 to 20) provide the following connections:
Eight analog input connections (CH0 IN to CH7 IN)
Eleven analog ground connections (AGND)
One calibration output terminal (CAL)
Screw terminal – pins 21-40
The screw terminals on the bottom edge of the RedLab 1608FS (pins 21 to 40) provide the following
connections:
Eight digital I/O connections (DIO0 to DIO7)
One external trigger source (TRIG_IN)
One external event counter connection (CTR)
One power connection (PC+5 V)
One SYNC terminal for external clocking and multi-unit synchronization (SYNC)
Eight ground connections (GND)
Pin 1Pin 20
Pin 21Pin 40

RedLab 1608FS User's Guide Functional Details
16
Main connector and pin out
Connector type Screw terminal
Wire gauge range 16 AWG to 30 AWG
20 19 18 17 CAL 16 15 14 13 12 11 10 9 8
AGND AGND AGND AGND CH7 IN AGND CH6 IN AGND
5 IN
AGND CH4 IN AGND
7CH3IN 6AGND 5CH2IN 4AGND 3CH1IN 2AGND 1CH0IN
CH
GND 40 PC +5V 39 CTR 38 TRIG_IN 37 SYNC 36 DIO7 35 GND 34 DIO6 33 GND 32 DIO5 31 GND 30 DIO4 29 GND 28 DIO3 27 GND 26 DIO2 25 GND 24 DIO1 23 GND 22 DIO0 21
Analog input terminals (CH0 IN - CH7 IN)
You can connect up to eight analog input connections to the screw terminal containing pins 1 to 20 (CH0 IN
through CH7 IN.) Refer to the pinout diagram on page 3-16 for the location of these pins. We recommend that
you connect unused analog input terminals to ground terminals during operation. For example, if you are not
using terminal 15 (CH7 IN), connect this terminal to terminal 16 (AGND).
Input configuration
All of the analog input channels are configured for single-ended input mode. Each analog signal is referenced to
signal ground (AGND), and requires two wires:
The wire carrying the signal to be measured connects to CH# IN.
The second wire connects to AGND.
The input voltage ranges are ±10 V, ±5 V, ±2.0 V, ±1.0 V. The following image illustrates a typical single-
ended measurement connection.

RedLab 1608FS User's Guide Functional Details
17
Figure 5. Single-Ended measurement connection
For more information on analog signal connections
For more information on single-ended inputs, refer to the Guide to Signal Connections (this document is
available on our RedLab CD (root directory)).
Digital I/O terminals (DIO0 to DIO7)
You can connect up to eight digital I/O lines to the screw terminal containing pins 21 to 40 (DIO0 to DIO7).
Refer to the pinout diagram on page 3-16 for the location of these pins. You can configure each digital bit for
either input or output. All digital I/O lines are pulled up to USB +5 V with a 47 K resistor (default). You can
request the factory to configure the resistor for pull-down to ground if desired.
When you configure the digital bits for input, you can use the RedLab 1608FS digital I/O terminals to detect the
state of any TTL-level input. Refer to the switch circuit shown in Figure 6 and 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 6. Digital connection DIO0 detecting the state of a switch
Pin 40
GND
Pin 30
PC +5V
Pin 21
DIO0
Pin 1
CH0 IN
Pin 2
AGND

RedLab 1608FS User's Guide Functional Details
18
+5V+GND
DIO0
Figure 7. Schematic showing switch detection by digital channel DIO0
For more information on digital signal connections
For general information regarding digital signal connections and digital I/O techniques, refer to the Guide to
Signal Connections (available our RedLab CD (root directory)).
Power terminals
The PC +5 V connection (pin 39) is on the bottom screw terminal of the RedLab 1608FS. Refer to the pinout
diagram on page 3-16 for the location of this pin. This terminal draws power from the USB connector. The
+5 V screw terminal is a 5 volt output that is supplied by the computer.
Caution! The +5 V terminal is an output. Do not connect to an external power supply or you may damage
the RedLab 1608FS and possibly the computer.
The maximum total output current that can be drawn from all RedLab 1608FS connections (power, analog, and
digital outputs) is 500 mA. This maximum applies to most personal computers and self-powered USB hubs.
Bus-powered hubs and notebook computers may limit the maximum available output current to 100 mA.
The RedLab 1608FS alone draws 150 mA of current from the USB +5 V supply. Once you start running
applications with the RedLab 1608FS, each DIO bit can draw up to 2.5 mA. The maximum amount of +5 V
current available for experimental use, over and above that required by the RedLab 1608FS, is the difference
between the total current requirement of the RedLab 1608FS (based on the application), and the allowed current
draw of the computer platform (500 mA for desktop computers and self-powered hubs).
With all outputs at their maximum output current, you can calculate the total current requirement of the RedLab
1608FS USB +5 V as follows:
(RedLab 1608FS @ 150 mA) + (8 DIO @ 2.5 mA ea) = 170 mA
For an application running on a computer or powered hub, the maximum available excess current is 500 mA −
170 mA = 330 mA. This number is the total maximum available current at the PC+5 V screw terminals.
Meilhaus Electronic highly recommends that you figure in a safety factor of 20% below this maximum current
loading for your applications. A conservative, safe user maximum in this case would be in the 250-300 mA
range.
Since some laptop computers running on battery power only allow up to 100 mA, the RedLab 1608FS may be
above that allowed by the computer. In this case, you must either purchase a self-powered hub or operate the
laptop computer from an external power adapter.
Ground terminals
The 11 analog ground connections provide a common ground for all RedLab 1608FS input channels. Eight
ground connections provide a common ground for the DIO, TRIG_IN, CTR, SYNC and PC +5 V connections.
Refer to the pinout diagram on page 3-16 for the location of the AGND and GND terminal pins.

RedLab 1608FS User's Guide Functional Details
19
Calibration terminal
The CAL connection (pin 17) is an output you should use only to calibrate the RedLab 1608FS. Refer to the
pinout diagram on page 3-16 for the location of this pin. Calibration of the RedLab 1608FS is software-
controlled by InstaCal.
Counter terminal
The CTR connection (pin 38) is a TTL-level input to a 32-bit event counter. Refer to the pinout diagram on page
3-16 for the location of this pin. The internal counter increments when the TTL level transitions from low to
high. The counter can count frequencies of up to 1 MHz.
SYNC terminal
The SYNC connection (pin 36) is a bidirectional I/O signal. You can use it for two purposes:
Configure as an external clock input to externally source the A/D conversions. The SYNC terminal
supports TTL-level input signals of up to 50 kHz.
Configure as an output to synchronize with a second RedLab 1608FS and acquire data from 16 channels.
Refer to the pinout diagram on page 3-16 for the location of this pin. For more information, refer to page 3-23.
Trigger terminal
The TRIG_IN connection (pin 37) is an external digital trigger input. You can configure this terminal with
software for either rising or falling edge.
Accuracy
The overall accuracy of any instrument is limited by the error components within the system. Quite often,
resolution is incorrectly used to quantify the performance of a measurement product. While "16-bits" or "1 part
in 65536" does indicate what can be resolved, it provides little insight into the quality, or accuracy, of an
absolute measurement. Accuracy specifications describe the actual measurement that can be relied upon with a
RedLab 1608FS.
There are three types of errors which affect the accuracy of a measurement system:
offset
gain
nonlinearity
The primary error sources in the RedLab 1608FS are offset and gain. Nonlinearity is small in the RedLab
1608FS, and is not significant as an error source with respect to offset and gain.

RedLab 1608FS User's Guide Functional Details
20
Figure 8 shows an ideal, error-free, RedLab 1608FS transfer function. The typical calibrated accuracy of the
RedLab 1608FS is range-dependent, as explained in the "Specifications" chapter of this document. We use a
±10 V range as an example of what you can expect when performing a measurement in this range.
-10V
+10V
Inp ut Vo lta g e
065535
Output Code
32768
Figure 8. Ideal ADC transfer function
The RedLab 1608FS offset error is measured at mid-scale. Ideally, a zero volt input should produce an output
code of 32768. Any deviation from this is an offset error. Figure 9 shows the RedLab 1608FS transfer function
with an offset error. The typical offset error specification for the RedLab 1608FS on the ±10 V range is
±1.66 mV. Offset error affects all codes equally by shifting the entire transfer function up or down along the
input voltage axis.
The accuracy plots in Figure 9 are drawn for clarity and are not drawn to scale.
-10V
+10V
Inp ut Vo lta g e
065535
Offset= 1.66mV
Ideal
Ac tua l
Output Code
1.66mV
32768
Figure 9. ADC transfer function with offset error