Data Sheet

ManualsBrandsDevantech ManualsMagnetic Sensors / CompassTilt Compensated Magnetic Compass (CMPS14)

CMPS14 – documentation

Introduction

The CMPS14 is our 5th generation tilt compensated compass. Employing a 3-axis magnetometer, a 3-axis gyro

and a 3-axis accelerometer. At the core of the module is the superb BNO080 running algorithms to remove the

errors caused by tilting of the PCB. The module also allows the calibration to be stopped and instead rely on a

static calibration profile.

Power supply requirements are flexible, you can feed between 3.3 - 5v and the module draws a nominal 18mA

of current. A choice of serial or I2C interfaces can be used for communication.

Overview of outputs

Heading, 16 bit – 2 outputs, one calculated by Bosch and one by us

Heading, 8 bit – 0-255 scaled for simpler requirements

Pitch – +/- 0-90° or +/- 0-180°

Roll – +/- 0-90°

Raw sensor outputs – 3 x 16 bit integers for each of the Magnetometer, accelerometer and gyro

Mode selection

Serial or I2C mode is easily selected with the state of the mode pin. Note the CMPS14 looks at the mode

selection pin at power-up only.

3.3v-5v

SDA/TX

SCL/RX

Mode

Factory use

0v ground

For I2C the mode pin can be left open or pulled to the supply voltage, for serial mode the mode pin should be

connected to 0v ground.

Summary of content (7 pages)

PAGE 1
CMPS14 – documentation Introduction The CMPS14 is our 5th generation tilt compensated compass. Employing a 3-axis magnetometer, a 3-axis gyro and a 3-axis accelerometer. At the core of the module is the superb BNO080 running algorithms to remove the errors caused by tilting of the PCB. The module also allows the calibration to be stopped and instead rely on a static calibration profile. Power supply requirements are flexible, you can feed between 3.3 - 5v and the module draws a nominal 18mA of current.
PAGE 2
I2C Mode Register 0x00 0x01 0x02, 0x03 0x04 0x05 0x06, 0x07 0x08,0x09 0x0A,0x0B 0x0C, 0x0D 0x0E, 0x0F 0x10, 0x11 0x12, 0x13 0x14, 0x15 0x16, 0x17 0x1C, 0x1D 0x1E Function Command register (write) / Software version (read) Compass Bearing 8 bit, i.e. 0-255 for a full circle Compass Bearing 16 bit, i.e. 0-3599, representing 0-359.9 degrees. register 2 being the high byte.
PAGE 3
Calibration of the CMPS14 The CMPS14 is shipped with a static factory calibration, but the module is able to automatically update its calibration with algorithms running in the background if desired. To achieve background calibration the user just needs to turn the functionality on and perform the required simple movements. Changing the calibration configuration To change the configuration write the following to the command register 0x98, 0x95, 0x99 with a 20ms delay after each of the three bytes.
PAGE 4
Changing the I2C Bus Address To change the I2C address of the CMPS14 you must have only one module on the bus. Write the 3 sequence commands in the correct order followed by the address with 20ms between writes. Example; to change the address of a compass currently at 0xC0 (the default shipped address) to 0xC2, write the following to the command register 0 at address 0xC0: (0xA0, 0xAA, 0xA5, 0xC2 ) with a 20ms delay after each of the first three bytes.
PAGE 5
Serial mode Communication settings The Serial mode operates over a link with a default baud rate of 9600 bps (no parity, 2 stop bits) and 3.3v-5v signal levels. This is not RS232. Do not connect RS232 to the module, the high RS232 voltages will irreversibly damage the module.
PAGE 6
Calibration of the CMPS14 The CMPS14 is shipped with a static factory calibration, but the module is able to automatically update its calibration with algorithms running in the background if desired. To achieve background calibration the user just needs to turn the functionality on and perform the required simple movements.
PAGE 7
Board dimensions