Here you can find some details about the Arduino Mega 9DOF Bluetooth Shield

 

Work in progress, have to add the tools and some comments.
Last change on 10/17/2014

 

 

You want a bare PCB? Just email me. [email protected]

We used these sensors, bought at www.sparkfun.com

ADXL345, HMC5843, LY530, LPR530 (approx. 52 dollar)

Have used these bluetooth modules, bought at www.tme.eu

BTM-112 or BTM-222 (approx. 15 dollar)

 

 

Three combinations of the same board, still one combination to go.... On the right a complete board with all sensors and with a Class 2 bluetooth module. On the top a board with just a Class 2 bluetooth module and at the bottom a Class 1 bluetooth board. We are busy building a fourth one, a standalone one with an Atmega328p on board.

 

 

This works great. Mix solder paste with flux and use this only on the bottom-pads of the sensors.

 

 

 

 
 

The board can also be used standalone. You have to put an Atmega328p on the board, USB-connector, FT232RL.

What is the impact on the Arduino Mega when you mount this shield?
 

Used are:
SCL (21), SDA (20)
RXD1/TXD1 (19/18 - when using Bluetooth)
Analog 0 - ZOUT-4X, Analog 1 - XOUT-4X, Analog 3- YOUT-4X
Analog 6 - Vref2, Analog 7 - Vref1
Digital 34 - ST, Digital 33 - PD and Digital 32 - HP.

 
 

On the right the ADXL345, connected to the I2c-bus, and when connected well, you will find it in the I2c-scanner.

This is the Bascom-AVR code for the I2c-scanner.
When the ADXL345 and the HMC5843 are fixed on the board you should see this in Hyperterminal

On &HA6 (ADXL345) and on &H3C (HMC5843) you see your devices.

In the datasheet of the HMC5843 I read about 7-bit address &H1E,
bit 0 of the 8-bit address of this device is the Read/Write bit.

001 1110 is &H1E but if you put the Read or the Write bit at the end
you will get 0011 1100 and that is our &H3C

Same for the ADXL345
101 0011 is &H53 but if you add the Read or Write bit
you get 1010 01100 &HA6
 
 

HMC5843 magnetometer on the right.
When we increased the C9 from 10 uF to 20 uF we have seen a big improvement.

In the middle LY530 - Yaw.

 
 

LPR530 - Pitch and Roll.

 
 

 

 

Level conversion is done between the Arduino Mega RXD1/TXD1 and the BTM-112/BTM-220.
SMD BC848 (NPN) and BC858 (PNP).

BTM-112 bluetooth Class 2 on top

Or, a BTM-220 bluetooth Class 1 on the bottom

 
 

Antenna, 30,61 mm to be exact

 
 

How do you get the name in your Bluetooth-module? And how do you put it on 57600 baud?

 
 

 

 
 

Arduino Mega, 9DOF Bluetooth Shield and on top a prototype of a LCD Shield.

 
 
 

Still two things to work out. A Nokia 6100 display and a stand-alone 9DOF Bluetooth version.

Well, display working. We had to make a small DC-DC step-up converter to get about 9 volts for the backlight of the Nokia 6100. Have tested with the Epson and with the Philips version. Both working correct.

And here the DC-DC step up converter in it's place

Tested with a MC34063 the way Sparkfun is doing it's step-up conversion,
but the results with a MAX202 were better. Still have to figure out, do you
blow-up a MC34063 when there is no load on it's output?

You only need three capacitors to get the 9.5 volts.

Here the PCB, it is very SMALL
 
 

You want to see it at work? Click on the picture.

 

Thanks to:


Thanks to Mark Alberts
the creator of Bascom-AVR
www.mcselec.com
 

Thanks to Natalius Kiedro
He wrote the Bascom-AVR KixRazor software
 

Thanks to Theo Kleijn
www.pa0kn.nl
 

Thanks to Sparkfun
www.sparkfun.com

Flags can be downloaded at www.3DFlags.com

Ben Zijlstra - Ben's HobbyCorner - 2010