Hi everyone.good day to you all. I need a help on HC11 input capture.
I am doing a tachometer project. If any one can provide help for me on 
the below;
1) which method i need to use for this.Is event counting or period 
counting.
2) i need alogritham on this counting. As i did some but no luck.Is 
not accurate as I expect.

I am using mc68hc11e9cfn3. Pulsed to TIC1 are taken from distributor 
of the engine through a simple filter circuit. The pulse a clear as my 
osciloscope read out at maximum rev. Pls help on this as my project 
are reaching the deadline.Thanks
	

--- In m68HC11@m68H..., "srsh78" <srsh78@...> wrote:
>
> Hi everyone.good day to you all. I need a help on HC11 input capture.
> I am doing a tachometer project. If any one can provide help for me on 
> the below;
> 1) which method i need to use for this.Is event counting or period 
> counting.
> 2) i need alogritham on this counting. As i did some but no luck.Is 
> not accurate as I expect.
> 
> I am using mc68hc11e9cfn3. Pulsed to TIC1 are taken from distributor 
> of the engine through a simple filter circuit. The pulse a clear as my 
> osciloscope read out at maximum rev. Pls help on this as my project 
> are reaching the deadline.Thanks
>

I have done similar for motor speed control and found using time to be
the easiest. It is also good to use pulse shaping (a high-speed
Schmidt) to get consistent edges for accurate timing.

Dianne