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RedLab 1608FS
USB-based
Analog and Digital I/O Module
User's Guide
Document Revision 1.4 E, January, 2008
© Copyright 2008, Meilhaus Electronic™
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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
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RedLab 1608FS User's Guide
Power................................................................................................................................................................27
General .............................................................................................................................................................28
Environmental ..................................................................................................................................................28
Mechanical .......................................................................................................................................................28
Main connector and pin out..............................................................................................................................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 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“.
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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
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.
®
Windows® operating
Figure 1. RedLab 1608FS
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RedLab 1608FS User's Guide Introducing the RedLab 1608FS
A
A
A
A
A
A
A
A
RedLab 1608FS block diagram
RedLab 1608FS functions are illustrated in the block diagram shown here.
USB
G= 1, 2, 5, 10
Full-speed
USB 2.0
Compliant
Interface
16
DIO
SYNC
Screw terminal I/O connector
CAL
TRIG_IN
CAL
8
USB
Microcontroller
32k x 16
SRAM
1616
SPI
/D 0
/D 1
/D 2
/D 3
/D 4
/D 5
Screw terminal I/O connector
/D 6
/D 7
32-bit
Event Counter
1 channel
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).
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RedLab 1608FS User's Guide Introducing the RedLab 1608FS
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.
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Installing the RedLab 1608FS
What comes with your RedLab 1608FS shipment?
The following items are shipped with the RedLab 1608FS.
Hardware
RedLab 1608FS
Chapter 2
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.
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RedLab 1608FS User's Guide Installing the RedLab 1608FS
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: +49 (0) 89/8901660
Fax: +49 (0) 89/89016628
E-Mail: support@meilhaus.com
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 1.1 and 2.0 update." 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,
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.
Found New Hardware popup balloons (Windows XP) or dialogs (other
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RedLab 1608FS User's Guide Installing the RedLab 1608FS
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.
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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.
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External components
The RedLab 1608FS has the following external components, as shown in Figure 3.
USB connector
LED
Screw terminal banks (2)
Screw terminal
Pins 21 to 40
LED
Figure 3. RedLab 1608FS
Screw terminal
Pins 1 to 20
USB connector / cable
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.
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.
LED Illumination
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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.
Pin 1 Pin 20
Pin 21 Pin 40
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 (
Eleven analog ground connections (
One calibration output terminal (
CH0 IN to CH7 IN)
AGND)
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 (
One external trigger source (
One external event counter connection (
One power connection (
One SYNC terminal for external clocking and multi-unit synchronization (
DIO0 to DIO7)
TRIG_IN)
CTR)
PC+5 V)
SYNC)
Eight ground connections (
GND)
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Main connector and pin out
Connector type Screw terminal
Wire gauge range 16 AWG to 30 AWG
5 IN
AGND
AGND
AGND
AGND
CH7 IN
AGND
CH6 IN
AGND
AGND
CH4 IN
AGND
CH
201918
17 CAL161514131211109
8
7CH3 IN
6AGND
5CH2 IN
4AGND
3CH1 IN
2AGND
1CH0 IN
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 singleended measurement connection.
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Pin 1
CH0 IN
Pin 2
AGND
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).
Pin 40
GND
Pin 30
PC +5V
Pin 21
DIO0
Figure 6. Digital connection DIO0 detecting the state of a switch
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DIO0
+5V+GND
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.
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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 softwarecontrolled 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.
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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.
Input Volta ge
+10V
Output Code
0
32768
65535
-10V
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.
Input Volt a g e
+10V
Ideal
0
Ac tu al
Offset= 1.66mV
32768
1.66m V
65535
Output Code
-10V
Figure 9. ADC transfer function with offset error
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RedLab 1608FS User's Guide Functional Details
Gain error is a change in the slope of the transfer function from the ideal, and is typically expressed as a
percentage of full-scale. Figure 10 shows the RedLab 1608FS transfer function with gain error. Gain error is
easily converted to voltage by multiplying the full-scale input (±10 V) by the error.
The accuracy plots in Figure 10 are drawn for clarity and are not drawn to scale.
Input Voltage
+10V
Idea l
Gain error = +0.04%, or +4mV
Gain erro r = -0.04%, or -4mV
Ac t ua l
Output Code
0
32768
65535
-10V
Figure 10. ADC Transfer function with gain error
For example, the RedLab 1608FS exhibits a typical calibrated gain error of ±0.04% on all ranges. For the ±10 V
range, this would yield 10 V × ±0.0002 = ±4 mV. This means that at full scale, neglecting the effect of offset for
the moment, the measurement would be within 4 mV of the actual value. Note that gain error is expressed as a
ratio. Values near ±FS (±10 V) are more affected from an absolute voltage standpoint than are values near midscale, which see little or no voltage error.
Combining these two error sources in Figure 11, we have a plot of the error band of the RedLab 1608FS at ±full
scale (±10 V). This plot is a graphical version of the typical accuracy specification of the product.
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The accuracy plots in Figure 11 are drawn for clarity and are not drawn to scale.
Ideal +1.66mV + 4mV
Idea l
Id eal -(1.66m V + 4m V)
Input Vo ltage
+10V
1.66m V
0
Figure 11. Error band plot
32768
-10V
Ideal +1.66mV + 4mV
Ideal
Ideal -(1.66mV + 4mV)
Output Code
65535
Gain queue
The RedLab 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 RedLab 1608FS. The gain list is made up of a channel number and range setting. An
example of an eight-element list is shown in the table below.
Sample channel gain queue list
Element Channel Range
0 CH0 BIP10V
1 CH1 BIP5V
2 CH2 BIP10V
3 CH3 BIP1V
4 CH4 BIP2V
5 CH5 BIP10V
6 CH6 BIP1V
7 CH7 BIP5V
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 RedLab 1608FS, it does produce a useless full-scale
reading. It can also introduce a long recovery time due to saturation of the input channel.
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Synchronizing multiple units
You can connect the SYNC pin of two RedLab 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 RedLab
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 InstaCal. By default, the
SYNC pin is set for pacer input. To synchronize a master RedLab 1608FS with a slave RedLab 1608FS and
acquire data from 16 channels, follow the steps below:
1. Run InstaCal.
2. Double-click on the RedLab 1608FS listing on the PC Board List on the InstaCal main form. The
Board Configuration dialog displays.
3. Configure the SYNC pin of the master RedLab 1608FS for pacer output:
o Double-click on the RedLab 1608FS that you want to configure as the master. The
Configuration
o Click to select the
dialog opens.
Enable Sync output check box and then click OK.
Board
4. Configure the SYNC pin of the slave RedLab 1608FS for pacer input:
o Double-click on the RedLab 1608FS that you want to configure as the slave. The Board
Configuration dialog displays.
o Make sure that the
Enable Sync output check box is not checked (unchecked is the default setting).
5. Connect the SYNC pin on the master RedLab 1608FS to the SYNC pin on the slave RedLab 1608FS.
6. Set the Universal Library EXTCLOCK option with cbAInScan()/AInScan() for the slave RedLab
1608FS to enable pacer output.
An example of a master/slave configuration is shown below.
Master
Slave
RedLab 1608FS
USB-1608FS
Configure the
SYNC pin for output
SYNC pin
pin 36
Slave
RedLab 1608FS
Configure the
SYNC pin for the input
Set the Universal Libary
EXTCLOCK option with
cbAInScan () /AInScan ()
for the slave RedLab 1608FS
Figure 12. Configuring for synchronous data acquisition
When you are operating one RedLab 1608FS, do not set the EXTCLOCK option unless you are using an external
clock for A/D pacing.
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Chapter 4
Specifications
Typical for 25 °C unless otherwise specified.
Specifications in italic text are guaranteed by design.
Analog input section
Table 1. Analog input specifications
Parameter Conditions Specification
A/D converter type 16-bit successive Approximation type
Number of channels 8 single-ended
Input configuration Individual A/D per channel
Sampling method Simultaneous
Absolute maximum input voltage CHx IN to GND. ±15 V max
Input impedance 100 MOhm, min
Input ranges Software selectable ±10 V, ±5 V, ±2 V, ±1 V
Sampling rate
Throughput
Gain queue
Resolution 16 bits
No missing codes 15 bits
Crosstalk Signal DC-25 KHz -80 dB
CAL output User calibration source
CAL output accuracy (Note 2) ±0.5% typ, ±1.0% max
CAL current ±5 mA max
Trigger source Software selectable External digital: TRIG_IN
Note 1: Maximum throughput scanning to PC memory is machine dependent. While the majority of XP
equipped PC’s we tested allowed acquisition at the maximum rates, a few would not. The lowest
maximum rate we observed on an XP equipped PC during multi-channel testing was 95 kS/s,
aggregate. The rates specified are for Windows XP only. Maximum rates on operating systems that
predate XP may be less and must be determined through testing on your machine.
Scan to PC memory
Burst scan to 32 k sample FIFO
Software paced 500 S/s all channels
Scan to PC memory (Note 1)
Burst scan to 32 k
sample FIFO
0.6 S/s to 50 kS/s, software
programmable
20 S/s to 50 kS/s, software
programmable
= (100 kS/s) / (# of channels), max of
50 kS/s for any channel
= (200 kS/s) / (# of channels), max of
50 kS/s for any channel
Software configurable. Eight elements,
one gain element per channel.
0.625 V, 1.25 V, 2.5 V, 5.0 V, software
selectable
Note 2: Actual values used for calibration are measured and stored in EEPROM.
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RedLab 1608FS User's Guide Specifications
Table 2. Calibrated absolute accuracy
Range Accuracy (mV)
±10 V 5.66
±5 V 2.98
±2 V 1.31
±1 V 0.68
Table 3. Accuracy components - All values are (±)
Range % of Reading Gain error at FS (mV) Offset (mV)
±10 V 0.04 4.00 1.66
±5 V 0.04 2.00 0.98
±2 V 0.04 0.80 0.51
±1 V 0.04 0.40 0.28
Table 4 summarizes the noise performance for the RedLab 1608FS. Noise distribution is determined by
gathering 50 K samples with inputs tied to ground at the user connector. Samples are gathered at the maximum
specified sampling rate of 50 kS/s.
Table 4. Noise performance
Range Typical counts LSBrms
±10 V 10 1.52
±5 V 10 1.52
±2 V 11 1.67
±1 V 14 2.12
Digital input/output
Table 5. Digital I/O specifications
Digital type CMOS
Number of I/O 8 (DIO0 through DIO7)
Configuration Independently configured for input or output
Pull-up/pull-down configuration
Input high voltage 2.0 V min, 5.5 V absolute max
Input low voltage 0.8 V max, –0.5 V absolute min
Output high voltage (IOH = –2.5 mA) 3.8 V min
Output low voltage (IOL = 2.5 mA) 0.7 V max
Power on and reset state Input
All pins pulled up to Vs via 47 K resistors (default).
Positions available for pull down to ground. Hardware
selectable via zero ohm resistors as a factory option.
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RedLab 1608FS User's Guide Specifications
External trigger
Table 6. External trigger specifications
Parameter Conditions Specification
Trigger source (Note 3) External digital TRIG_IN
Trigger mode Software selectable
Trigger latency 10 µs max
Trigger pulse width 1µs min
Input high voltage 4.0 V min, 5.5 V absolute max
Input low voltage 1.0 V max, –0.5 V absolute min
Input leakage current ±1.0µA
Note 3: TRIG_IN is a Schmitt trigger input protected with a 1.5K Ohm series resistor.
Edge sensitive: user configurable for
CMOS compatible rising or falling edge.
External clock input/output
Table 7. External clock I/O specifications
Parameter Conditions Specification
Pin name SYNC
Pin type Bidirectional
Output Outputs internal A/D pacer clock. Software selectable direction
Input
Input clock rate 50 kHz, maximum
Input 1µs min Clock pulse width
Output 5µs min
Input leakage current ±1.0µA
Input high voltage 4.0 V min, 5.5 V absolute max
Input low voltage 1.0 V max, –0.5 V absolute min
IOH = –2.5 mA 3.3 V min Output high voltage (Note 4)
No load 3.8 V min
IOL = 2.5 mA 1.1 V max Output low voltage (Note 4)
No Load 0.6 V max
Note 4: SYNC is a Schmitt trigger input and is over-current protected with a 200 Ohm series resistor.
Receives A/D pacer clock from external
source.
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RedLab 1608FS User's Guide Specifications
Counter section
Table 8. Counter specifications
Pin name (Note 5) CTR
Counter type Event counter
Number of channels 1
Input type TTL, rising edge triggered
Input source CTR screw terminal
Resolution 32 bits
Schmidt trigger hysteresis 20 mV to 100 mV
Input leakage current ±1µA
Maximum input frequency 1 MHz
High pulse width 500 ns min
Low pulse width 500 ns min
Input high voltage 4.0 V min, 5.5 V absolute max
Input low voltage 1.0 V max, –0.5 V absolute min
Note 5: CTR is a Schmitt trigger input protected with a 1.5K Ohm series resistor.
Memory
Table 9. Memory specifications
Data FIFO 32,768 samples, 65,536 bytes
EEPROM 1,024 bytes
EEPROM configuration
Address range Access Description
0x000-0x07F Reserved 128 bytes system data
0x080-0x1FF Read/write 384 bytes cal data
0x200-0x3FF Read/write 512 bytes user area
Microcontroller
Table 10. Microcontroller specifications
Type High performance 8-bit RISC microcontroller
Program memory 16,384 words
Data memory 2,048 bytes
Power
Parameter Conditions Specification
Supply current USB enumeration < 100 mA
Supply current (Note 6) Continuous mode 150 mA
+5 V USB power available
(Note 7)
Output current (Note 8) 350 mA max
Note 6: This is the total current requirement for the RedLab 1608FS which includes up to 10 mA for the status
Connected to self-powered hub
Connected to externally-powered root port hub
LED.
4.5 V min, 5.25 V max
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RedLab 1608FS User's Guide Specifications
Note 7: "Self-powered hub" refers to a USB hub with an external power supply. Self-powered hubs allow a
connected USB device to draw up to 500 mA. "Root port hubs" reside in the PC’s USB host
Controller. The USB port(s) on your PC are root port hubs. All externally-powered root port hubs
(desktop PC’s) provide up to 500 mA of current for a USB device. Battery-powered root port hubs
provide 100 mA or 500 mA, depending upon the manufacturer. A laptop PC that is not connected to an
external power adapter is an example of a battery-powered root port hub. If your laptop PC is
constrained to the 100 mA maximum, you need to purchase a self-powered hub.
Note 8: This refers to the total amount of current that can be sourced from the USB +5 V and digital outputs.
General
Device type USB 2.0 (full-speed)
Device compatibility USB 1.1, USB 2.0
Environmental
Operating temperature range 0 to 70 °C
Storage temperature range -40 to 70 °C
Humidity 0 to 90% non-condensing
Mechanical
Dimensions 79 mm (L) x 82 mm (W) x 25 mm (H)
USB cable length 3 meters max
User connection length 3 meters max
Main connector and pin out
Connector type Screw terminal
Wire gauge range 16 AWG to 30 AWG
Pin Signal Name Pin Signal Name
1 CH0 IN 21 DIO0
2 AGND 22 GND
3 CH1 IN 23 DIO1
4 AGND 24 GND
5 CH2 IN 25 DIO2
6 AGND 26 GND
7 CH3 IN 27 DIO3
8 AGND 28 GND
9 CH4 IN 29 DIO4
10 AGND 30 GND
11 CH5 IN 31 DIO5
12 AGND 32 GND
13 CH6 IN 33 DIO6
14 AGND 34 GND
15 CH7 IN 35 DIO7
16 AGND 36 SYNC
17 CAL 37 TRIG_IN
18 AGND 38 CTR
19 AGND 39 PC +5V
20 AGND 40 GND
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Meilhaus Electronic GmbH
Fischerstrasse 2
D-82178 Puchheim, Germany
Phone: +49 (0)89 89 01 66-0
Fax: +49 (0)89 89 01 66-77
E-Mail: sales@meilhaus.com
http://www.meilhaus.com
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