So as I understand from the previous post

connect the the pulsing circuit to t0 /t1 configure timer 0 /1 for counter mode with external interrupt

then two problems I face are how do I keep track of time i.e. 10ms in my case

10ms is the window period in which I would like to count the number of pulse coming.

and how do I take care of baud rate generation I am using th1 for that if I use timer1 for keeping track of time?


you can see my current circuit here http://www.ikraft.biz/netbaba/project/CKT.gif
(I can make the change in circuit as I have not got the final PCB done)

my asm file (I need to comment it more )
http://www.ikraft.biz/netbaba/p...lagv12.txt

I even tried using the example code by keil http://www.keil.com/download/...se.zip.asp
which measures pulse width on INT0 and dumps the value to pc but that too didn't work

I feel there may be some problem in my circuit

A small explanation of my circuit
The circuit is used to measure water level in a tank.
There are two plates at a distance of 5mm from each other which forms a parallel plate capacitor
this capacitor is connected to the 555 timer in astable MV ,So as the capvalue changes due change in level of water the pulse width keeps changing ,hence number of pulses in say 10ms will be different for different heights.
I need to read this from 555 and then dump it to PC
where the frontend should take care of the display side.
Ya this is just a college project and not the real capacitance type level transmitters and I also know many will be telling me not to ask for code or help but my demo on 15th march was not too good I need to make it work in about 10 days before my theory exams.

thanks Deepak