ECG Signal and Temperature on Bluetooth

[keat007]

Hello, I am currently working on a 4 weeks project and I have some troubles in our project.

What we are trying to do:

ECG Signal + Temperature --> Basic Stamp 2 --> Parallax Bluetooth EB500 --> Labview (Receive via Bluetooth Dongle)

Can it be done without Data Acquistion Card? We have no prior experience on Labview and trying very hard to figure out the proper way to transmit the signals. We are thinking to give up the thinking if it involves Data Acquisition Card as it's expensive and the time is way too short to learn the program well enough. Any advice? Thanks.

Best regards,

keat007

Nanyang Technological University

Singapore.

[ShaunR]

It's very easy to use bluetooth with Labview. There are a few examples in the examples directory.

I would suggest a PIC to aquire the data and interface via its UART to your Bluetooth transmitter and you can use Labview to receive and chart/graph/analyse the data on a PC with your dongle.. A PIC is small, and cheap but requires C knowledge (probably cost you about £5-£10 to build) but have UARTS, and several analogue and digital inputs - more than enough for your task. It would also be very portable and could be battery powered (matchbox size?). If you go for labview for the acquisition then you will require another PC to run the labview run-time with some sort of compatible acquisition device, or something like cRIO, fieldpoint etc which can run labview (which are really overkill and expensive).

[keat007]

Thanks for the reply. Is it possible that we can use a separate UART chip rather than PIC? Is it the same to interface a UART chip onto a bluetooth?

[ShaunR]

QUOTE (keat007 @ May 17 2009, 06:14 AM)

Thanks for the reply. Is it possible that we can use a separate UART chip rather than PIC? Is it the same to interface a UART chip onto a bluetooth?

Not quite sure what your asking here.

You need to get your voltage measurement into a form that can be output to your bluetooth module.. For that you will need an analogue input of some description and an interface to your bluetooth module - A U(S)ART.

I've just been looking up the "StampII" and it seems it doesn't have an analogue input. It seems that these "Stamps" have a UART already so you can connect it to your bluetooth directly anyway. (people seem to be using them a lot for Boebots and controlling them using PDA's etc). But I'm afraid, if it doesn't have an analogue input, you cannot measure a voltage (easily). You can have an RC circuit and measure pules to try and make a rudimentry A2D converter, but I wouldn't recommend it for a medical application.

So your issue doesn't seem to be Labview. Its that your hardware can't measure voltage.

This is what others say about measuring voltages with a "Stamp" and they basically say that you need something else (like a PIC).

http://www.zonerocket.com/Voltage-checker-for-Basic-Stamp-II-robot-project-article5144--2.htm' rel='nofollow' target="_blank">Voltage Checker For Basic Stamp

[ShaunR]

Just hunting around on google (wonderful tool) and found this.

Tooth PIC

It would be ideal for your app and cheaper than bolting together all the different components your intending to use.

You only have a short time to develop. So I would suggest not faffing around trying to get different modules to work together and go for a one-box solution.

[keat007]

Thanks for the reply again. I am not really sure if Stamps have UART or not. However, what we are using is the bluetooth which can be fit into the development board directly and is able to connect to the PC via the Bluetooth transmitter and a Bluetooth dongle. Yes, even though it couldn't be used to measure voltage directly, but by implementing ADC0831 and some PBASIC codes, it should do the voltage measurement job. So basically, what we do not know is how to acquire the data using labview. Time is indeed really short and the budget is somehow limited.

[ShaunR]

QUOTE (keat007 @ May 17 2009, 02:25 PM)

Thanks for the reply again. I am not really sure if Stamps have UART or not. However, what we are using is the bluetooth which can be fit into the development board directly and is able to connect to the PC via the Bluetooth transmitter and a Bluetooth dongle. Yes, even though it couldn't be used to measure voltage directly, but by implementing ADC0831 and some PBASIC codes, it should do the voltage measurement job. So basically, what we do not know is how to acquire the data using labview. Time is indeed really short and the budget is somehow limited.

There are examples of acquiring via bluetooth in the Labview examples.

[keat007]

QUOTE (ShaunR @ May 17 2009, 11:21 PM)

There are examples of acquiring via bluetooth in the Labview examples.

------------------

That "Toothpick looked so cool I've just ordered a couple

Haha, sure. I will loook up those examples. So basically the U(S)ART is only to interface Basic Stamp and Bluetooth transmitter and actually has nothing to do with making the signal digital right??

Yes, it is cool, but I have no idea where to get them in Singapore. :headbang:

[ShaunR]

QUOTE (keat007 @ May 18 2009, 01:14 AM)

Haha, sure. I will loook up those examples. So basically the U(S)ART is only to interface Basic Stamp and Bluetooth transmitter and actually has nothing to do with making the signal digital right??

Yes, it is cool, but I have no idea where to get them in Singapore. :headbang:

Indeed. The USART is just a communications interface to the microcontroller to talk to other devices like a bluetooth or PC. Nearly all modern microcontrollers come with at least 1 (usually used for programming it) and many come with 2 or 3. With a USART (which has digital voltage levels) , you can wire directly to other comms chips to provide your microcontroller with virtually nay interface you desire (bluetooth, USB, RS485, RS232, WIFI etc).

The "Stamp" is just another flavour of microcontroller (from what I can tell) like a PIC or ARM. The only problem with the Stamp is it only has digital IO and you need to measure an analogue signal. You can (as you pointed out) add additional hardware to convert the analogue signal into a digital one, but I see that as doing it the hard way

As my Toothpic is on its way I decided to look at the software for programming it. You can download a free toolset but I think what will be of more interest to you is that they have existing firmware for acquisition. I think if your looking to get up and running quickly and not too bothered if you use Labview or not, then it might be worth reading this. Looks like the server is in the bluetooth device (ike a webserver) so data can be viewed on anything from a PC to a mobile phone.

http://www.flexipanel.com/Docs/DARC-II%20DS382.pdf' rel='nofollow' target="_blank">DARC II

Oh. they ship to Singapore from that link I gave you

[wavestorm1986]

Hi every body ..... my project is the same and i got the same module even from parallax and i can say that i had few problem with it coz i cant measure the voltage out, i am sure that we need to program the PIC to make it interface with the PC, my question is : sending the signal from the ECG circuit to the module should pass through a PIC so i heard that there are sometrhing called NI-SPY which can show hows the data transmitting using the serial port so anyway can try and see ?

By the way the new idea is about finding an audio module and buy the UART to USB and solder then together, and can use acquire sound to get the signal so what about this idea ??