TD-CMP04 Compass v2

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TechDesign Electronics

Front view.

TD-CMP04 Compass v2.

• Small electronic compass.
• Dimensions: 45x36x15mm.
• Suited for robotics and other various applications.
• Low current LED indicator (stays lit when heading North) for power saving.
• Accuracy 1...2° @ 7Hz measurement..
• Easy calibration.
• Serial RS232 readout possible.
• One multifunction push button for power on and calibration.

• Low power operation with one small +12V MN21 battery.
• Power supply input range is +3.0V ... +12V, only 2...5 mA active, 190µA when sleeping.
• Auto sleep mode after 30 seconds (LED goes off.)
• Runs on a PIC18F25K20 at 8 MhZ along with an HMC5883 sensor.

• Assembled and fully tested TD-CMP v2Compass now available.
• Project source code and schematics can be purchased separately.

 Module Software Updated on Dec. 27, 2011.

Long press (5 seconds) to start calibration.

Stays lit when heading (top of the box as shown above) is close to North (from heading 355° to 5°)

Flashing slowly when requesting calibration (push button for 5 seconds.)

Stays lit for calibration (for 10 seconds.)

Low current red LED for power saving.

1. Have the compass placed on a leveled (flat) surface.
2. Long press on the push button (5 seconds) to start calibration.
3. The LED starts flashing slowly.
4. Continue to press for 5 seconds.
5. The LED will stop flashing and now stays on.
6. Now slowly rotate the compass 2-3 times , whilst keeping it leveled (flat.)
7. Wait until the LED starts flashing again.
8. Check whether the North indicator (LED stays on when heading North.)

front view, cover removed

bare PCB - populated backside