Need help in interfacing flow sensors and to display it on TV

Hello everyone,

I am a beginner and having an idea in interfacing a water flow
sensor's output to the beagle board and from the board i should
display it on the TV(via S-video out).

I want to display the amount of water used by the person on his TV.
that's why i am using a water flow sensor
What are the steps i shud do...plz help me out from basics and its my
dream project..

I got the sensor G1/2 which will give 4.5 V output and i have the rev C4 board

How to program the water flow sensor's output pulses on beagle board
to display it as "Liters Used : " on TV.

Please just tell the start up kind of things, i will catch and learn
from there... i dont know how to start this concept on this board...


First u need to install some OS to the board (preferably Ubuntu).
Then u should write some interfacing programs either in pyhton or qt to get a graphical display.

I would agree with Gokul.C install the Ubuntu OS and then try your
hand on clutter library available on ubuntu. Since python is already
installed you should check out pyclutter. Its very easy and neat and
monitoring solutions can be created from scratch.

once you install ubuntu you might want to update your repository and
install the python-clutter package

The output of the flow sensors is usually via UART connect the RX to
TX and TX to RX and monitor the port for values. Once you do that use
the Python-clutter library and create a monitoring application
monitoring that port. In order to learn PyClutter I would recommend
this link. This link starts with not only the creation of a whole new
pyclutter app but its actually a monitoring app. So, you're
practically in luck to have found it.

Next, once you are done with the app, the output can be (obviously)
and easily be obtained from DVI port to an anolog Television. You can
check your TV's specifications ofcourse or get a converter. You can
google the converter and trust me its easily available in Delhi (I am
making an assumption you are located in India, if not you can most
definitely search DigiKey or any such site. )

This should get you started, please feel free to ask further on.
Good Luck

oh thanks., i will work on it but plz guide me through a reference
program which has a graphical display... is there any links with u..?
if so, it ll be very useful.. thanks a lot for ur reply

Well if you want to build it from scratch you'll have to go through
the trouble of building a program yourself. But as I mentioned (with a
link) you'll find clutter easy.

Thanks a lot pronoy, i am happy to see ur reply...!
I am a student from tamilnad and i am learning as per ur way and i
will update u about the progress of my project part by part and i
ordered beagleboard XM... which board will be most suitable for this
application? Will u help me further, when i chose XM cortex?

Thanks once again

I'll help as far as I can, keep your progress and queries posted on
this mailing list, if there's something I can't help you with, I am
sure someone will intervene and give you a way out

all the best

A typical flow sensor has a frequency output signal, such as say 50 Hz /l/min.

There are several kind of such devices with different scaling of this value.
The signal pin needs a pull up, so as a first try you might want to pull it up to 1.8V and get rid of any level translator.

Than you can poll the line every say 1ms, and count the number of transitions on this line in a period (the longer the period, the slower the readout and the higher the accuracy). 100 ms is a typically a good compromise for this period.

You should configure the pin as an input line.


oh thanks a lot sir... i am working on it...

may i know how to do the configuration of pins as input etc.. i m
learning on it so if u put me deep in some links then i will find a
confident way sir.. thanx

Hello sir,
How to capture the data from sensor through dev/ttyUSBO?

Like below kind of accessing the network data traffic...

Is there any other way to capture the data through clutter app...?