low - high + interrupt

[Alanis]

Hi !
How to read out this low - high sample:
L- L- L- H- H- H- H- L- L- H- H- L- L- H- H

Maybe with some interrupt routine ?
The chip that am using is 16F877.

Alan

[Alanis]

Hi guys !

Do you have and idea how to make this ?
In general, i dont know how to define that L-H read out.
e.g. how to read the levels if i get 3 time L L L or H H H ...

Alan
p.s. incoming data is passed at speed of 9600 B/s.

[Guest]

Setup a timer with the correct speed and enable interupt.
Att each interrupt read the value from the actual pin.
Start the timer in the middle of the first bit.
To do this you must have a reference, i.e. start bit or something like that to know when to start.

[Alanis]

Setup a timer with the correct speed and enable interupt.
-If my internal ring oscillator is 8 MHZ, what is the correct timer setup ?

Start the timer in the middle of the first bit.
- I dont understand this part....