Screenshots:

Schematics: (click for full resolution image)

Main Connections:

Module header diagram		Header pinouts
		JP2 pins RS232   JP3 pins I²C / TEMP SENSOR   JP4 pins POWER SOURCE                     1 +5V   1 +5V   1 EXT (from JP3)   2 RX   2 SCL/SPEED1   2 COMMON   3 GND   3 SDA   3 USB   4 TX   4 GND / TEMP SENSOR -/SPEED2               5 ADJUST               6 TEMP SENSOR +                           * Note: pin 1 is marked by red in the diagram

Power Source: JP4: Connect pin 2 to pin 3 to power the module directly from USB. Connect pin 1 to pin 2 when powered externally via JP3, pin 1.

New: Increase sampling speed from 12,5/second to 25/second: connect SPEED1 to SPEED2 (JP3, pin4 to JP3, pin2.)

LCD contrast Adjust: Connect pin 5, JP3 to +5V before powering up. Release when the desired the contrast is reached.

Tilt/Roll Calibration: (TD-CMP02 and TD-CMP03 only):

• First place the module on a completely flat surface, power up.
• Then shortly apply +5V (pin 1, JP2) to ADJUST (pin 5, JP3) Release after 1 second.
• Check readings when applying tilt/roll to the module. Repeat the calibration procedure if necessary. Done.

Compass Calibration: (do not touch the PCB or chips whilst calibrating.)

• First place the module on a completely flat surface, power up, head to North (position as shown in diagram and picture above), then turn the module slowly 360° (make 2-3 full clockwise and/or counter-clockwise spins.)
• Now apply +5V (pin 1, JP2) to ADJUST (pin 5, JP3) Wait for 8-10 seconds; the LED will flash 3 times. Release the ADJUST pin from +5V. Power off and on.
• Check compass readings when heading the module to N, S, E, W. Repeat the calibration procedure if necessary. Done.

Module RESET: apply GND to MCLR pin.

Temperature sensor: (TD-CMP03 only): The external LM335Z sensor connects to JP3 pin 4 and 6. No temperature will be displayed when the sensor is removed.

RS232 interface:

JP2 provides the interface to connect to your COM port and hyper terminal. Communications @ 115200 bpS, 8N1.

Also used for bootloading (module software update.) Check under the download section below for the latest version. Bootloading of the HEX-file can be done with Tiny Bootloader 1.91

RS232 terminal screen @115200 bps

I²C interface: JP3 allows us to connect to another µC. The module is the slave device on address 0xa0. It can be read via a simple EXT_EEPROM command. Download this I²C CCS C example to see how to connect I²C with a 18F452. Don't forget to change the POWER SOURCE (JP4) and connect pin 1 to pin 2.

Internal 8 bit registers are:

• i2c_buffer[7]= t_hi;                     // temperature high byte (unsigned int8)
  i2c_buffer[6]= t_lo;                     // "    "    "    "    low byte
• i2c_buffer[5]= adxl_y;                 // roll (signed int8)
  i2c_buffer[4]= adxl_x;                 // tilt " " " "
  i2c_buffer[3]= cmp_UMSB;
  i2c_buffer[2]= cmp_LMSB;
  i2c_buffer[1]= cmp_ULSB;         // compass 0..359
  i2c_buffer[0]= cmp_LLSB;         // " " " "

Reading the module (ccs c code):

• #include <2401.c>              // for I²C EXT.EEPROM emulation used by slave i²c TD-CMP modules
• ...
• int8 cmp_LLSB,cmp_ULSB;
• int16 compass_degrees;
• signed int8 adxl_x,tilt_degrees;
• signed int8 adxl_y,roll_degrees;
• ...
• init_ext_eeprom();             // init TD-CMP module as slave I²C ext.EEPROM
• ...
• cmp_LLSB = READ_EXT_EEPROM(0x00);     // read TD-CMP register 0 (cmp_LLSB)
• cmp_ULSB = READ_EXT_EEPROM(0x01);     // read TD-CMP register 1 (cmp_ULSB)
• adxl_x = READ_EXT_EEPROM(0x04);             // read TD-CMP register 4 (adxl_x) Tilt
• adxl_y = READ_EXT_EEPROM(0x05);             // read TD-CMP register 5 (adxl_y) Roll
• ...
• compass_degrees= ((int16)cmp_ULSB<<8)+cmp_LLSB;    // here's the data we needed
• tilt_degrees= adxl_x;
• roll_degrees= adxl_y;

USB interface: is HID (Human Interface Device) on PID=0461, VID= 1023 Each packet is 8 bits long (4 bytes address and 4 bytes data.)

• Address 0x01000004: cmp_UMSB,  cmp_LMSB, cmp_ULSB, cmp_LLSB (compass)
• Address 0x01000003: t_hi, t_lo (temperature), adxl_y (roll), adxl_x (tilt) signed int8

Low power LED: Will light up shortly when USB is connected and enumerated. Also the LED will blink several times, according to the capital direction it is facing:

• North: 1x
• East: 2x
• South: 3x
• West: 4x

Downloads: right-click & save as

 

WARNING: may not be duplicated for any commercial use whatsoever without explicit consent from the author (c) Michel Bavin, TechDesign Electronics.

Windows Example program setup: 023- TDCMP setup.msi  - January 28, 2009. Written in C# Visual Studio .NET, compatible with Windows XP and Vista. Important Note: You need to have Microsoft .NET Framework 1.1 (or higher) installed to get the executable running.  I²C Connection CCS C Source Code: 023_i2c_v02_18F452.zip  - May 18, 2006. Connects a 18F452 to the TD-CMP module using I²C to read data.  TD-CMP Module HEX: 023_v34.HEX  - November 26, 2009. Can be bootloaded to the module through the RS232 port (JP2) and Tiny Bootloader 1.91  Schematics: gif, pdf.  PCB Diagram: gif.  Partslist: html. Get this page as PDF

Module PIC CCS C Source Code, Schematics (eagle) , C# code : not released, but you can buy a license on our Products page.

Info & datasheet:

Tools:

Check out our development tools page.

The PIC code was made with the PCWH CCS compiler ($425,-); you can install Microchip's MPLAB IDE (click on the link and you can get it for free) with it to get things running smoothly.

Bootloading of the modules is done with the excellent Tiny PIC bootloader, through RS232 (JP2).

Eagle 4.11e was used for the schematic & PCB layout. 

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