LabJack Introduction - Web Services Overview
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Transcript LabJack Introduction - Web Services Overview
ECE 102
Engineering Computation
Chapter 9
LabJack Introduction
Dr. Herbert G. Mayer, PSU
Status 10/2/2015
For use at CCUT Fall 2015
Syllabus
LabJack HW Overview
LabJack Features
LabJack HW Control
Input & Output Channels
Digital Input Output\Analog Input
Analog Output
Summary
LabJack Hardware Overview
The LabJack U3 is a
basic external DAQ
unit that is used to
interface a computer
to the physical world.
Company website:
http://labjack.com
General tech support: http://labjack.com/support
U3-specific support: http://labjack.com/u3
2
What can a LabJack do?
Read the output of sensors which measure:
voltage, current, power, temperature
humidity, wind speed, force, pressure, strain
acceleration, RPM, light intensity, sound intensity
gas concentration, position, and many more
A LabJack brings this data into a computer where it can
be stored and processed.
Control things like motors, lights, solenoids, relays,
valves, and more.
3
LabJack Features
Model U3-LV (Low Voltage)
• 16 flexible I/O(digital input, digital output, or analog input)
• Up to 16 12-bit analog inputs (0 → 2.4 V or 0 → 3.6 V, SE or Diff)
• Maximum input stream rate of 2.5 → 50 kHz
• 2 analog outputs (10-bit, 0-5 V, 16 Hz)
• 4 additional digital I/O
• Up to 2 timers (pulse timing, PWM output, quadrature input)
• Up to 2 counters (32 bit each)
• USB 2.0/1.1 interface → Connect to computer via USB cable
• Windows, Linux, Mac drivers
Model U3-HV (High Voltage)
• First 4 FIOare replaced by dedicated HV analog inputs
• The HV inputs have ±10 V or -10/+20 V range
4
Model U3-LV Pinouts:
Model U3-HV Pinouts:
USB Port
USB Port
VS = +5 V DC
GND = ground
SGND
SPC
SGND
VS
VS
GND
DAC0
DAC1
FIO7
FIO6
GND
VS
VS
GND
FIO2
FIO3
FIO5
FIO4
GND
VS
VS
GND
FIO0
FIO1
DB15 Port
FIOxx
= flexible I/O
AINx
= analog input
DACx
= analog output
SGND
SPC
SGND
VS
VS
GND
DAC0
DAC1
FIO7
FIO6
GND
VS
VS
GND
AIN2
AIN3
FIO5
FIO4
GND
VS
VS
GND
AIN0
AIN1
DB15 Port
5
DB15 & USB Ports
EIO6
GND
8
EIO2
EIO4
7
15
6
14
EIO0
5
13
EIO5
EIO7
CIO3
4
12
CIO1
3
11
EIO1
EIO3
VS
2
10
1
9
DB15
(EIO& CIO)
CIO2
GND
screw
terminals
CIO0
DB15 Female Connector Pinout
VS = +5 V DC
GND = ground
EIOxx = 8 flexible I/O
CIOx = 4 dedicated digital I/O
USB
(type B)
status LED
6
LabJack HW Control
LabJack company-supplied software
Windows configuration utility: LJControlPanel
3rd party software
e.g., DAQFactory Express
User developed software
Supported languages include:
C/C++, VC6, .NET, Java
Python, VB6, PureBasic
MATLAB
LabVIEW, VEE
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Ground & VS
GND is an electrical
ground point.
(USB → PC → AC mains)
VS is a fixed +5 V DC
output voltage.
These can be used to
power external circuits.
Maximum current: 450 mA
SGND
SPC
SGND
VS
VS
GND
DAC0
DAC1
FIO7
FIO6
GND
VS
VS
GND
FIO2
FIO3
FIO5
FIO4
GND
VS
VS
GND
FIO0
FIO1
8
Input & Output Channels
An I/Ochannel is a hardware circuit inside the LabJack
that can
Sense an input signal
Generate an output signal
Supported signals:
Digital (binary levels)
Analog (continuous levels)
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LabJack Channels (U3-LV model)
FIO (16: FIO0-FIO7 terminals
EIO0-EIO7 DB15)
DAC (2: DAC0-DAC1 terminals)
Flexible - can be any one
of the following:
Digital input or output
Analog input
Timer
Counter
Analog output only
CIO (4: CIO-CIO3 DB15)
SGND
SPC
SGND
VS
VS
GND
DAC0
DAC1
FIO7
FIO6
GND
VS
VS
GND
FIO2
FIO3
FIO5
FIO4
GND
VS
VS
GND
FIO0
FIO1
Digital input or output only
10
Digital Input Output
Input → Sense a low or high input voltage
+3.3 V
100K Ω
Maximum Input Limit
FIO: -10 V to +10 V
EIO: -6 V to +6 V
Sense
O
utput-Low → Force a low output voltage
FIO: R = 550 Ω
EIO/CIO: R = 180 Ω
Sense: 0 = Low, 1 = High
R
GND
Output = 0 V
O
utput-High → Force a high output voltage
FIO: R = 550 Ω
EIO/CIO: R = 180 Ω
R
+3.3 V
Output = +3.3 V (no load)
11
Analog Input
Single-ended
O
ne analog input is required
Input voltage is measured with respect to ground
Maximum Input Limit
FIO: -10 V to +10 V
EIO: -6 V to +6 V
Input
AINx
Ground
GND
Sense: 0 to +2.44
Input values < 0 V are reported as 0 V.
Input values > +2.44 V are reported as +2.44 V
Differential
Two analog inputs are required
Input
AINx
Reference
AINy
The voltage difference between the input and the
reference is measured (i.e., VInput – VReference)
12
Analog Input Sampling Modes
Command/Response (Software based timing)
Program initiates an input request
LabJack measures a single sample
Program reads the sample data value
Easy to set up but slow sampling rate
Stream (Hardware based timing)
Program initiates an input request
LabJack hardware continuously samples the input
Program reads an entire block of sample data
Complicated to set up but fast sampling rate
13
Analog Output
The DAC can generate an output voltage with a
specified amplitude (within limits).
DACx
Output
GND
Ground
Output Range
DAC: +0.04 V to +4.95 V
The output filter limits the output sampling rate to
approximately 16 Hz.
14
Timer & Counter
The timer is for applications that require accurate
hardware-based timing.
Timer
In PWM mode, the timer generates a
pulse width modulated output signal.
FIO
A counter accumulates the number of falling edges (Hto-L signal transition) detected on an FIO.
1
2
3
FIO
Counter (32-bit register)
00000000000000000000000000000011
= 310
This keeps track of
the number of
times an event has
occurred.
15
Summary
Screw Terminals
• FIO (8: FIO0-FIO7)
• Digital input (-10 V to +10 V)
• Digital output (L: 0 V, H: +3.3 V)
• Analog input (-10 V to +10 V)
[Usable range: 0 V to +2.44 V]
• Timer / Counter
• DAC (2: DAC0-DAC1)
• Analog output (0 V to +4.95 V)
• VS (6)
• Fixed DC voltage (+5 V)
• GND (5)
• Ground reference (0 V)
DB15 Port
• EIO (8: EIO0-EIO7)
• Digital input (-6 V to +6 V)
• Digital output (L: 0 V, H: +3.3 V)
• Analog input (-6 V to +6 V)
[Usable range: 0 V to +2.44 V]
• Timer / Counter
• CIO (4: CIO0-CIO3)
• Digital input (-6 V to +6 V)
• Digital output (L: 0 V, H: +3.3 V)
• VS (1)
• Fixed DC voltage (+5 V)
• GND (2)
• Ground reference (0 V)
Warnings
• Do not exceed rated voltage limits for inputs.
• Never apply an external voltage into an output.
• Do not short-circuit the LabJack.
• Do not overtighten screw terminals.
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REFERENCE: I/O Specifications
The following tables contain more detailed
specifications for the LabJack's hardware.
VS Parameter
O
utput Voltage
Maximum Current
Conditions
Min
Typ
Max
Units
Self-Powered
4.75
5.0
5.25
V
Bus-Powered
4.0
5.0
5.25
V
Self-Powered
450
mA
Bus-Powered
50
mA
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Digital I/O Parameter
Conditions
Min
Typ
Max
Units
Low Level Input Voltage
-0.3
0.8
V
High Level Input Voltage
2
5.8
V
FIO
-10
10
V
EIO/CIO
-6
6
V
Maximum Input Voltage
O
utput Low Voltage
No Load
0
V
FIO
Sinking 1 mA
0.55
V
EIO/CIO
Sinking 1 mA
0.18
V
EIO/CIO
Sinking 5 mA
0.9
V
No Load
3.3
V
FIO
Sourcing 1 mA
2.75
V
EIO/CIO
Sourcing 1 mA
3.12
V
EIO/CIO
Sourcing 5 mA
2.4
V
FIO
6
mA
EIO/CIO
18
mA
FIO
550
Ω
EIO/CIO
180
Ω
O
utput High Voltage
Short Circuit Current
O
utput Impedance
18
Analog Input Parameter
Max
Units
0
2.44
V
Differential, LV
-2.44
2.44
V
Special, LV
0
3.6
V
Max AIN Voltage to GND
Valid Readings, LV
-0.3
3.6
V
Max AIN Voltage to GND
No Damage, FIO
-10
10
V
No Damage, EIO
-6
6
V
Typical Input Range
Conditions
Min
Single-Ended, LV
Resolution
Integral Linearity Error
Differential Linearity Error
Typ
12
bits
±0.05
% FS
±1
counts
Effective Resolution (RMS)
QuickSampleOff
>12
bits
Noise-free Resolution
QuickSampleOff
11.0
bits
Single-Ended, LV
1.2
mV
Diff., Special, LV
2.4
mV
LV
40
MΩ
Input Impedance
Source Impedance
LongSettlingOff, LV
10
kΩ
LongSettlingOn, LV
200
kΩ
19
Analog Output Parameter
NominalOutput Range
Conditions
Min
No Load
@ ±2.5 mA
Typ
Max
Units
0.04
4.95
V
0.225
4.775
V
Slew Rate
0.4
V/ms
Resolution
20
bits
Absolute Accuracy
5% to 95% FS
±5.0
% FS
Short Circuit Current
Max to GND
45
mA
50
Ω
Source Impedance
O
utput frequency
Sinusoidal
16
Hz
20
Timer & Counter Modes
Mode
Description
Mode
Description
0
16-bit PWM output
7
Frequency output
1
8-bit PWM output
8
Quadrature input
2
Period input (32-bit, rising edges)
9
Timer stop input (odd timers only)
3
Period input (32-bit, falling edges)
10
System timer low read (default)
4
Duty cycle input
11
System timer high read
5
Firmware counter input
12
Period input (16-bit, rising edges)
6
Firmware counter input (debounced)
13
Period input (16-bit, falling edges)
Allowed channels:
FIO4-FIO7, EIO0-EIO3
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