i m making the spirometer using ir led & sensor... a fan is in between them.. when a person blow to the fan... it will rotate nd there will be change in ir sensir output... when the flap of the fan cuts the ir ray there is pulse genrated on output side... now i have to count this pulses using 89c51 microcontroller and display it on lcd...
i m ready with my sensor part... pls help me with controller part... about circuit, interfacing with lcd nd programing....

 

help me...

 

If it was me, I'd use a bicycle computer. Cheap and built just for this type of thing, with lots of ready-made features.

 

i m ready with my sensor part... pls help me with controller part... about circuit, interfacing with lcd nd programing....

Since you have the sensor part, it looks like this you are looking for uC and LCD interface and programming. Maybe the forum moderators will move this to the appropriate forum...Embedded Systems and Microcontrollers.

Ken

 

how can i get bicycle computer?? what is it?

 

is freq to voltage converter is usefull after sensor part??
pls reply me

 

There should not be a need for an external frequency to voltage converter. You can do the frequency-to-flow rate conversion in software.

Ken

 

in which software?

 

You said you were using a 89c51 microcontroller. Do you not know how to program it? I can't help you with that. Maybe you can explain what you have for resources and your knowledge level.

Ken

 

freq to flow rate conversion can not done by 89c51... i dnt knw whwt to do...

 

Hello,

An other way of measuring airflow is using a thermal anemometer:
http://www.fonema.se/anemom/anemom.html

Bertus

 

freq to flow rate conversion can not done by 89c51... i dnt knw whwt to do...

why cant it be done?