PNI TCM3 User manual

User Guide
User Guide
TCM3 & TCM5
Tilt-Compensated Compass Module

PNI Sensor Corporation Doc #1007537 r12
TCM3 & TCM5 User Manual- Sept 2011 Page 2
Table of Contents
1COPYRIGHT & WARRANTY INFORMATION.....................................................................................3
2PNI CORPORATION’S TCM3 & TCM5................................................................................................4
2.1 PERFORMANCE SPECIFICATIONS .......................................................................................5
2.1.1 Heading Specifications.................................................................................................5
2.1.2 Magnetometer Specifications.......................................................................................5
2.1.3 Tilt Specifications..........................................................................................................5
2.1.4 Calibration.....................................................................................................................5
2.1.5 Mechanical Specifications............................................................................................5
2.1.6 I/O Specifications..........................................................................................................6
2.1.7 Power Specifications ....................................................................................................6
2.1.8 Environmental Specifications .......................................................................................6
2.2 MECHANICALS.........................................................................................................................7
2.2.1 Mechanical Drawing.....................................................................................................7
2.2.2 18 in. Cable Assembly..................................................................................................8
3INSTALLATION OF THE TCM.............................................................................................................9
3.1 ELECTRICAL CONNECTIONS.................................................................................................9
3.2 WHERE TO INSTALL..............................................................................................................10
3.3 MECHANICALLY MOUNTING THE TCM...............................................................................11
4USING THE TCM ................................................................................................................................13
4.1 TCM STUDIO ..........................................................................................................................13
4.1.1 Install the TCM Studio program onto a Windows system: .........................................13
4.1.2 Connection Tab ..........................................................................................................14
4.1.3 Configuration Tab.......................................................................................................14
4.1.4 Calibration Tab ...........................................................................................................19
4.1.5 Test Tab......................................................................................................................20
4.1.6 Data Logger Tab.........................................................................................................21
4.1.7 System Log Tab .........................................................................................................21
4.2 USER CALIBRATION..............................................................................................................22
4.2.1 Calibration Theory......................................................................................................23
4.2.2 Hard and Soft Iron Effects..........................................................................................23
4.2.3 Pitch and Roll .............................................................................................................24
4.2.4 Recommended Calibration Procedure For Taking The Minimum Number Of Sample
Points 25
4.2.5 Declination Value........................................................................................................27
4.2.6 Other Limitations ........................................................................................................28
4.3 BINARY PROTOCOL –RS232 INTERFACE .........................................................................29
4.3.1 Datagram Structure....................................................................................................29
4.3.2 Parameter Formats.....................................................................................................29
4.3.3 Commands & Communication Frames ......................................................................32
4.4 CODE EXAMPLES..................................................................................................................44
4.4.1 Binary TCM High Performance Protocol C Header File & CRC-16 Function ............44
4.4.2 Binary TCM Protocol C++ Communication Examples ...............................................47

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1 Copyright & Warranty Information
© Copyright PNI Sensor Corporation 2005
All Rights Reserved. Reproduction, adaptation, or translation without prior written permission is prohibited, except
as allowed under copyright laws.
Revised March 2011. For most recent version visit our website at www.pnicorp.com
PNI Sensor Corporation
133 Aviation Blvd, Suite 101
Santa Rosa, CA 95403, USA
Tel: [phone]
Fax: [phone]
Warranty and Limitation of Liability. PNI Sensor Corporation ("PNI") manufactures its TCM products (“Products”)
from parts and components that are new or equivalent to new in performance. PNI warrants that each Product to be
delivered hereunder, if properly used, will, for one year following the date of shipment unless a different warranty
time period for such Product is specified: (i) in PNI’s Price List in effect at time of order acceptance; or (ii) on PNI’s
web site (www.pnicorp.com) at time of order acceptance, be free from defects in material and workmanship and will
operate in accordance with PNI’s published specifications and documentation for the Product in effect at time of
order. PNI will make no changes to the specifications or manufacturing processes that affect form, fit, or function of
the Product without written notice to the OEM, however, PNI may at any time, without such notice, make minor
changes to specifications or manufacturing processes that do not affect the form, fit, or function of the Product. This
warranty will be void if the Products’ serial number, or other identification marks have been defaced, damaged, or
removed. This warranty does not cover wear and tear due to normal use, or damage to the Product as the result of
improper usage, neglect of care, alteration, accident, or unauthorized repair.
THE ABOVE WARRANTY IS IN LIEU OF ANY OTHER WARRANTY, WHETHER EXPRESS, IMPLIED, OR
STATUTORY, INCLUDING, BUT NOT LIMITED TO, ANY WARRANTY OF MERCHANTABILITY,
FITNESS FOR ANY PARTICULAR PURPOSE, OR ANY WARRANTY OTHERWISE ARISING OUT OF ANY
PROPOSAL, SPECIFICATION, OR SAMPLE. PNI NEITHER ASSUMES NOR AUTHORIZES ANY PERSON
TO ASSUME FOR IT ANY OTHER LIABILITY.
If any Product furnished hereunder fails to conform to the above warranty, OEM’s sole and exclusive remedy and
PNI’s sole and exclusive liability will be, at PNI’s option, to repair, replace, or credit OEM’s account with an
amount equal to the price paid for any such Product which fails during the applicable warranty period provided that
(i) OEM promptly notifies PNI in writing that such Product is defective and furnishes an explanation of the
deficiency; (ii) such Product is returned to PNI’s service facility at OEM’s risk and expense; and (iii) PNI is satisfied
that claimed deficiencies exist and were not caused by accident, misuse, neglect, alteration, repair, improper
installation, or improper testing. If a Product is defective, transportation charges for the return of the Product to
OEM within the United States and Canada will be paid by PNI. For all other locations, the warranty excludes all
costs of shipping, customs clearance, and other related charges. PNI will have a reasonable time to make repairs or
to replace the Product or to credit OEM’s account. PNI warrants any such repaired or replacement Product to be
free from defects in material and workmanship on the same terms as the Product originally purchased.
Except for the breach of warranty remedies set forth herein, or for personal injury, PNI shall have no liability for any
indirect or speculative damages (including, but not limited to, consequential, incidental, punitive and special
damages) relating to the use of or inability to use this Product, whether arising out of contract, negligence, tort, or
under any warranty theory, or for infringement of any other party’s intellectual property rights, irrespective of
whether PNI had advance notice of the possibility of any such damages, including, but not limited to, loss of use,
revenue or profit. In no event shall PNI’s total liability for all claims regarding a Product exceed the price paid for
the Product. PNI neither assumes nor authorizes any person to assume for it any other liabilities.
Some states and provinces do not allow limitations on how long an implied warranty lasts or the exclusion or
limitation of incidental or consequential damages, so the above limitations or exclusions may not apply to you. This
warranty gives you specific legal rights and you may have other rights that vary by state or province.

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2 PNI Corporation’s TCM3 & TCM5
Thank you for purchasing PNI’s TCM3 (pn 12606) or TCM5 (pn 12608) tilt-compensated compass
module. You have chosen a product that represents the largest step forward in compass technology for
many years. The TCM is a state-of-the-art, low power, high performance electronic tilt compensated
compass sensor module.
The TCM uses advanced algorithms, with hard iron and soft iron corrections, to provide highly accurate
heading information, in any orientation (TCM5 only), at latitudes up to 85. The output information of the
unit will indicate accurate attitude position of the module and can be used in systems requiring full 360
rotation (TCM5 only). This has been accomplished by integrating 3-axis magnetic field sensing, 3-axis tilt
sensing, and compass heading into a single module, which is one of the smallest in the market. With its
small size, the TCM is capable of fitting into today’s size sensitive systems. These advantages make PNI
Corporation’s TCM the choice for applications that require the highest accuracy and performance
anywhere in the world.
The TCM combines PNI Corporation’s patented Magneto-Inductive (MI) sensors and measurement circuit
technology with a 3-axis MEMS accelerometer for unparalleled cost effectiveness and performance. The
magnetic sensors and accelerometers are calibrated to operate from -40 to 85C; hence the
measurement is very stable over temperature and inherently free from offset drift.
The TCM’s advantages make it suitable for many applications, including:
High-performance solid state navigation equipment
High-performance attitude measurement
IMU system integration
3-axis magnetic field sensing
Robotics systems
Laser range finders
Drilling applications
With its many potential applications, the TCM provides a command set designed with flexibility and
adaptability in mind. Many parameters are user-programmable, including reporting units, a wide range of
sampling configurations, output damping, and more. We hope the TCM will help you to achieve the
greatest performance from your target system. Thank you for selecting PNI’s TCM compass.
Note: Several versions of the TCM exist, as the product line has evolved over the years. Throughout this
manual the term “TCM” refers to the TCM 3 and TCM 5. Other versions available from PNI include the
current TCM XB and TCM 5LT, and the legacy TCM 2.5 and TCM 2.6. (Availability subject to change.)

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2.1 Performance Specifications
2.1.1 Heading Specifications
Parameter
TCM3
TCM5
Units
Accuracy with <65º of tilt
0.5º
0.3º
Deg RMS
Accuracy with <80º of tilt
0.8º
0.5º
Deg RMS
Resolution
0.1º
0.1º
Deg RMS
Repeatability[1]
0.05º
0.05º
Deg RMS
Max Dip Angle
85º
85º
Deg
[1] Repeatability is based on statistical data at ±3 sigma limit about the mean.
2.1.2 Magnetometer Specifications
Parameter
TCM3
TCM5
Units
Calibrated Field Measurement Range
±80
±80
µT
Magnetic Resolution
±0.05
±0.05
µT
Magnetic Repeatability
±0.1
±0.1
µT
2.1.3 Tilt Specifications
Parameter
TCM3
TCM5
Units
Pitch Accuracy
0.2º
0.2º
Deg RMS
Roll Accuracy
0.2º for pitch <65º
0.5º for pitch <80º
0.2º for pitch <65º
0.5º for pitch <80º
1.0 for pitch <86º
Deg RMS
Tilt Range
±80º
±90º pitch
±180º roll
Deg
Tilt Resolution
<0.01º
<0.01º
Deg
Tilt Repeatability[1]
0.05º
0.05º
Deg RMA
1] Repeatability is based on statistical data at ±3 sigma limit about the mean.
2.1.4 Calibration
Parameter
TCM3
TCM5
Hard Iron Calibration
Yes
Yes
Soft Iron Calibration
Yes
Yes
2.1.5 Mechanical Specifications
Parameter
TCM3
TCM5
Units
Dimensions (LxWxH)
3.5 x 4.3 x 1.3
3.5 x 4.3 x 1.3
cm
Weight
<7
<7
grams
Mounting Options
Screw mounts/Standoffs
Horizontal
Screw mounts/Standoffs
Horizontal or vertical
Connector for RS-232
9-pin
9-pin

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2.1.6 I/O Specifications
Parameter
TCM3
TCM5
Units
Time to Initial Good Data from
Power On1
<210
<210
msec
Time to Initial Good Data from
Sleep Mode1
<80
<80
msec
Maximum Sample Rate2
~30
~30
samples/sec
RS-232 Communication Rate
300 to 115200
300 to 115200
baud
Output Formats
Binary High Performance Protocol
[1] FIR taps set to “0”.
[2] The maximum sample rate is dependent on the strength of the magnetic field, and typically will be from 25 to 32
samples/sec.
2.1.7 Power Specifications
Parameter
TCM3
TCM5
Units
Supply Voltage
3.8 to 5 V (unregulated)
3.8 to 5 V (unregulated)
VDC
Current Draw at
maximum sample rate
20 typical
20 typical
mA
Sleep Mode
0.6 typical
0.6 typical
mA
2.1.8 Environmental Specifications
Parameter
TCM3
TCM5
Units
Operating Temperature
-40º to 85º
-40º to 85º
C
Storage Temperature
-40º to 85º
-40º to 85º
C

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2.2 Mechanicals
2.2.1 Mechanical Drawing
The default orientation for the TCM is for the silk-screened arrow to point in the “forward” direction. That
puts the edge opposite of the Molex connector as the front edge of the board.

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2.2.2 18 in. Cable Assembly



Molex p/n 51146-0900
Molex p/n 50641-8141
TCM Pin Descriptions
Pin
Wire Color
Description
1
Black
Power Ground
2
Gray
NC
3
Green
R2-232 Ground
4
Orange
NC
5
Violet
NC
6
Brown
NC
7
Yellow
TxD
8
Blue
RxD
9
Red
5 VDC

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3 Installation of the TCM
This section describes how to configure, program, and control the TCM in your host system. To install the
TCM into your system, follow these steps:
Make electrical connections to the TCM
Evaluate the TCM using the included TCM Studio Program
Choose a mounting location
Mechanically mount the TCM
Perform user calibration
Before you install the module, it can be evaluated with the TCM Studio outside of your system. Please
see section 4.1 TCM Studio.
3.1 Electrical Connections
Included with the TCM Interface Kit is a cable to allow for the unit to be connected to your host system.
On one end of the cable is the connector needed to mate with the TCM3/5. The cable’s wires are color
coded as indicated below.
PNI also has a 6-foot cable with a DB9 connector attached. Please contact PNI Corporation for purchas-
ing information.
TCM Pin Descriptions
Pin
Wire Color
Description
1
Black
Power Ground
2
Gray
NC
3
Green
R2-232 Ground
4
Orange
NC
5
Violet
NC
6
Brown
NC
7
Yellow
TxD
8
Blue
RxD
9
Red
5 VDC

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3.2 Where to Install
The TCM’s magnetometers’ wide dynamic range and its sophisticated calibration algorithms allow it to
operate in many environments. For optimal performance however, you should mount the TCM with the
following considerations in mind:
The TCM’s magnetometers should not saturate
The TCM can be user calibrated to correct for large static magnetic fields created by the host system.
However, each axis of the TCM’s magnetometers has a maximum dynamic range of ±80 µT; if the total
field exceeds this value for any axis, the TCM will not give accurate heading information. When mounting
the TCM, consider the effect of any sources of magnetic fields in the local environment that when added
to the earth’s field may saturate the TCM’s sensors. For example, large masses of ferrous metals such as
transformers and vehicle chassis, large electric currents, permanent magnets such as electric motors,
and so on.
Locate the TCM away from local sources of changing magnetic fields
It is not possible to calibrate for changing magnetic anomalies. Thus, for greatest accuracy, keep the
TCM away from sources of local magnetic anomalies that will change with time; for instance, electric
equipment that will be turned on and off or nearby ferrous bodies that will be changing positions. Make
sure the TCM is not mounted close to cargo or payload areas that may be loaded with large sources of
local magnetic fields.
The TCM should be mounted in a physically stable location
Choose a location that is isolated from excessive shock, oscillation, and vibration.
Testing
Testing should be performed in the early stages of development to understand the range of any distortion
fields and transients so that component placement can take this into consideration.
To determine the range of field distortion, place the compass in a fixed position, then move/energize
suspect components while observing the output to determine when they are an influence.

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To determine if the mounting locations magnetic field is within the dynamic range of the compass, the
following test should be performed:
With the compass mounted, rotate and tilt the systems in as many positions as possible. While doing so,
monitor the magnetometer outputs, observing if the maximum dynamic range is exceeded. It is
preferable to have some margin before hitting the dynamic range limit of the module.
3.3 Mechanically Mounting the TCM
Refer to the TCM Dimensional Specification later in this manual for the TCM board dimensions and the
orientation of the reference frame.
The TCM is factory calibrated with respect to the mounting holes, as shown below, thus it must be aligned
within the host system with respect to these mounting holes, not the board edges.

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Mounting Options
The TCM is able to be mounted in various positions to allow for greater flexibility. All reference points are
based on the white silk-screened arrow on the top side of the board.
Note: The board depicted below is for illustration purposes only and does not show the actual TCM
board.
TCM3/5 Mounting Options

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4 Using the TCM
TCM Studio
User Calibration
Binary Protocol
Code Examples
4.1 TCM Studio
The TCM Evaluation software communicates with the TCM through the COM port of your PC. It puts an
easy-to-use interface onto the Binary command language used by the TCM, so that instead of issuing
command codes manually, you can use buttons, check boxes, and dialog boxes. It reads the Binary
responses of the TCM output strings and formats its sensor data into labeled and easy-to-read data
fields. The program also includes the ability to log and save the outputs of the TCM to a file. All of this is
so that you may begin to learn the capabilities of the TCM while using the TCM Studio program’s more
friendly interface. Check the PNI website for the latest updates at www.pnicorp.com.
4.1.1 Install the TCM Studio program onto a Windows system:
1. Drag the “TCM Studio.exe” to the working directory of your computer.
2. Move the Quesa plug-in (Quesa.dll) into either the Windows System or System32 folder. Quesa
is the OpenGL rendering engine and the 3D Model of the TCMStudio will not run without it.
For Windows 2000/NT copy to: /WinNT/System32 folder
For Windows XP copy to: /Windows/System32 folder
To install the TCM Studio program onto a Mac OSX system:
1. Drag the “TCM Studio” to the working directory of your computer.
2. Move the Quesa plug-in (Quesa) to: /Library/CFMSupport

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4.1.2 Connection Tab
Initial Connection:
1. Select 38400 as the baud rate.
2. Select the serial port the unit is plugged into.
3. Click on the <Connect> button.
4. Once a connection is made the “Connected” light will turn green and the Module, Firmware Ver-
sion and Serial Number will be displayed.
Change Baud Rate:
1. Select new baud rate for the module.
2. Click on the <Power Down> button.
3. Select same baud rate for the computer.
4. Click on the <Power Up> button.
Change Modules:
Once connection has been made, the TCM Studio will remember the last settings. Any time a module is
switched out, clicking on the <Connect> button once the new module is attached will reestablish a
connection as long as the module baud rate is the same as the previous unit.
4.1.3 Configuration Tab
Note: No settings will be changed in the unit until the <SAVE> button has been selected.
Mounting Options:
Note: If the selection is grayed out or not listed the unit connected does not support this feature.
Refer to “Mechanically Mounting –mounting option” section for additional information on
mounting options.
Standard: When selected the unit is to be mounted with the main board in a horizontal position (the
Z axis magnetic sensor is vertical).
Standard 90 Degrees: When selected the unit is to be mounted with the main board in a horizontal
position but rotated so the arrow is pointed 90 degrees clockwise from the front of the host system.
Standard 180 Degrees: When selected the unit is to be mounted with the main board in a horizontal
position but rotated so the arrow is pointed 180 degrees from the front of the host system.
Standard 270 Degrees: When selected the unit is to be mounted with the main board in a horizontal
position but rotated so the arrow is pointed 270 degrees clockwise from the front of the host system.

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X Sensor Up: When selected the unit is to be mounted with the main board in a vertical position (the
X axis magnetic sensor is vertical).
X Sensor Up Plus 90 Degrees: When selected the unit is to be mounted with the main board in a
vertical position (the X axis magnetic sensor is vertical) and rotated 90 degrees clockwise from the
front of the host system.
X Sensor Up Plus 180 Degrees: When selected the unit is to be mounted with the main board in a
vertical position (the X axis magnetic sensor is vertical) and rotated 180 degrees from the front of the
host system.
X Sensor Up Plus 270 Degrees: When selected the unit is to be mounted with the main board in a
vertical position (the X axis magnetic sensor is vertical) and rotated 270 degrees clockwise from the
front of the host system.
Y Sensor Up: When selected the unit is to be mounted with the main board in a vertical position (the
Y axis magnetic sensor is vertical).
Y Sensor Up Plus 90 Degrees: When selected the unit is to be mounted with the main board in a
vertical position (the Y axis magnetic sensor is vertical) and rotated 90 degrees clockwise from the
front of the host system.
Y Sensor Up Plus 180 Degrees: When selected the unit is to be mounted with the main board in a
vertical position (the Y axis magnetic sensor is vertical) and rotated 180 degrees from the front of the
host system.
Y Sensor Up Plus 270 Degrees: When selected the unit is to be mounted with the main board in a
vertical position (the Y axis magnetic sensor is vertical) and rotated 270 degrees clockwise from the
front of the host system.
Z Sensor Down: When selected the unit is to be mounted with the main board in a vertical position
(the Z axis magnetic sensor is vertical).
Z Sensor Down Plus 90 Degrees: When selected the unit is to be mounted with the main board in a
vertical position (the Z axis magnetic sensor is vertical) and rotated 90 degrees clockwise from the
front of the host system.

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Z Sensor Down Plus 180 Degrees: When selected the unit is to be mounted with the main board in
a vertical position (the Z axis magnetic sensor is vertical) and rotated 180 degrees from the front of
the host system.
Z Sensor Up Plus 270 Degrees: When selected the unit is to be mounted with the main board in a
vertical position (the Z axis magnetic sensor is vertical) and rotated 270 degrees clockwise from the
front of the host system.

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North Reference:
Magnetic: When the “Magnetic” radio button is selected, heading will be relative to Magnetic North.
True: When the “True” radio button is selected, heading will be relative to True North. To use North
Heading in “True” mode, the declination needs to be set in the “Declination” window. Refer to “Using
the TCM Declination Value” section for more information.
Endianess:
Use to select either Big Endian or Little Endian; default is Big Endian.
Filter Settings:
Taps: Use to select either a 0 (no filter), 4, 8, 16, or 32 samples and apply the values to a FIR filter
prior to calculating the heading. These filters allow for a much more stable reading, but can make the
acquisition of the data by the program slower. The default setting is 32.
Acquisition Parameters:
Mode:
When “Poll” is selected the TCM Studio program requests the data from the unit, and once it
has been sent, the program will request the data again at the interval set in the “Poll Time”
box. If the time is set to 0 then the TCM Studio will request the data as soon as the previous
request has been fulfilled.
When “Push” is selected the unit will be in Interval Mode, which is internal to the unit. Once
the unit has been set to Interval Mode and the interval time has been set in the “Interval
Time” setting box, the unit will send out the preset data at the desired interval without prompt-
ing. If the interval is set to 0 then the unit will send the data as soon as the previous data
stream has been sent.
Acquire Time:
The “Acquire Time” setting box sets the time between samples taken by the unit. This is an
internal setting that is NOT tied to the time with which the unit transmits the data out to the
program or host.

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Flush Filters:
The filtering is set to only update the filter with the last sample taken, for example once the initial
32 samples are taken any new sample is added to the end with the first sample being dropped.
In the case where the “Acquire Time” is set to a value it would be prudent to set the unit to flush
the filter prior to calculating the heading. This flushing will require the unit to take 32 new
samples to use for the calculation.
Note: If the “Flush Filters” checkbox is checked, it will take longer for the unit to output updated data.
User Cal Settings:
Stability Checking:
By default the unit will wait for the readings to be stable for 3 consecutive readings when in
calibration mode prior to saving the sample for use in the calibration. This is why the unit must be
held steady between points during the User Calibration. This stability helps to ensure a proper
heading and allow for higher accuracy, but it also takes more time. If the user de-selects the
check box, then the unit will NOT wait for a stable reading and instead take a reading once the
minimum change between points threshold has been met.
Automatic Sampling:
When selected the unit will take a point once the minimum change requirement and the stability
check, if selected, has been satisfied. If the user wants to have more control over when the point
will be taken then Auto Sampling should be deselected. Once deselected, the <Take Sample>
button on the Calibration tab will be active. Selecting the <Take Sample> button will indicate to
the unit to take a sample once the minimum requirements are met.
Calibration Points:
The user can select the number of points to take during a calibration. The minimum number of
points needed for a successful calibration is 12. The unit will need to be rotated through at least
180 degrees in the horizontal plane with a minimum of at least 1 positive and 1 negative Pitch
and at least 1 positive and 1 negative Roll as part of the 12 points.
Enable 3D Model:
Some computer systems may not have the graphics capability to render the 3D Model, for this
reason it may be necessary to turn off this feature.

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Default:
This button will set the TCM Studio program back to the factory default settings.
Revert:
This button will have the TCM Studio program read the settings from the unit and display them on the
screen.
4.1.4 Calibration Tab
Note: The default settings of the unit are recommended for the highest accuracy and
quality of calibration.
Samples:
1. Click on the <Start> button to begin.
2. To take a sample point, the unit will need to be held steady for a short time. Once the window in-
dicates the next number, the unit can be moved some distance and held steady for the next sam-
ple. A minimum change of 30 degrees in heading or tilt is required for a sample to be taken. The
larger the distance between points the better. The amount of Pitch and Roll during the calibration
will determine the amount of Pitch and Roll the unit will be able to compensate for during use.
Once the pre-set number of samples has been taken the calibration is complete.
Note: The minimum points the unit can use for a successful calibration is 12. The unit will
need to be rotated through at least 180 degrees in the horizontal plane with minimum of at
least 1 positive and 1 negative Pitch and Roll as part of the 12 points.
Results:
1. Once the calibration is complete the “Coverage” window will indicate the quality of the calibration.
The X, Y, and Z values show a percentage of each vector that has been covered during the cali-
bration. The only way to get a Z value greater than 50% would be to take some points with the
unit upside-down. The value shown in µT refers to the standard deviation of the measured sam-
ples when compared to the calculated values. The smaller the number the better. If a better
score is needed, click on the <Start> button to begin a new calibration.
Note: The value in µT only refers to the quality of the calibration and NOT the accuracy of
the heading. It is possible to have a “good” calibration but poor accuracy if the field the unit
is exposed to during use is not the same as that which was present during the calibration.
2. If the calibration is sufficient then click on the <Save> button to save the calibration. If this button
is not selected then the unit will need to be recalibrated after a power cycle.

PNI Sensor Corporation Doc #1007537 r12
TCM3 & TCM5 User Manual- Sept 2011 Page 20
Current Configuration:
Stability Checking: Indicates if the Stability Checking option has been selected.
Automatic Sampling: Indicates if the Automatic Sampling option has been selected.
Number of samples is: Indicates the number of samples to be taken for the current calibration.
Options:
Audible Feedback: If selected the TCM Studio will give an audible signal once a calibration point
has been taken.
Clear:
This button will clear the user calibration in the unit. Once selected, the unit will revert back to its
factory calibration.
4.1.5 Test Tab
Current Reading:
Once the <GO> button is selected the unit will begin outputting Heading, Pitch and Roll information.
Selecting the <Stop> button or changing tabs will halt the output of the unit.
Contrast:
Reverses the background color of the current reading window.
Acquisition Settings:
This window indicates the pertinent setting information.
3D Model:
The helicopter will follow the movement of the attached module and give a clear representation of the
module’s orientation.