Declination Angle; Installation - Silicon Laboratories DIGITAL COMPASS-RD User Manual

DIGITAL COMPASS-RD

7. Declination Angle

The compass is calibrated at the Silicon Laboratories factory in Austin, Texas but because the angle of declination
varies with respect to geographic position, the compass must be calibrated again for the specific location of use to
achieve maximum accuracy. Table 1 provides this information for several major cities around the world.
Table 1. Angles of Declination for Selected Cities - February 2005
There are a number of resources available on the World Wide Web that compute angles of declination for any
location in the world. A "World Magnetic Model Calculator" is available from both the National Geophysical Data
Center and the British Geological Survey:
http://www.ngdc.noaa.gov/seg/geomag/jsp/struts/calcDeclination
http://www.geomag.bgs.ac.uk/gifs/wmm_calc.html
8. Compass Software
The included CD-ROM contains the Silicon Laboratories Compass Software and additional documentation. This
software allows the user to connect to the compass board and display the information on a PC. The following
sections detail the software installation process and connection options.

8.1. Installation

Use the following steps to install the compass software and USB drivers.
1. Insert the CD-ROM into your PC's CD-ROM drive. An installer will automatically launch, allowing you to install the
compass software. If the installer does not automatically start when you insert the CD-ROM, run
CompassDemoInstall.exe found in the root directory of the CD-ROM.
2. Follow the prompts to install the Compass Software and the CP210x drivers. These drivers are necessary for the
software to communicate with the board over the USB connection. If using Windows XP, logo testing warnings may
appear. Press the "Continue Anyway" button.
3. Connect the compass board to the PC with the included USB cable.
4. When the PC detects the new device it will open a "Found New Hardware Wizard" window.
5. Press "Next" after selecting the (Recommended) option.
6. Windows Logo testing warnings may appear. Press the "Continue Anyway" button.
7. Press "Finish" to finish installing the "CP210x USB Composite Device".
8. Repeat steps 5, 6 and 7 to install the "CP210x USB Bridge Controller".
8
Location
Austin, Texas
San Francisco, CA
Nuremberg, Germany
London, England
Paris, France
Tokyo, Japan
Rev. 0.1
Declination Angle (E)
5º 20'
14º 51'
1º 23'
4º 11'
–1º 13'
–6º 54'