help in my IR cut beam !

[asrock]

hello every one



i have a simple project that just detects an IR cut beam

i use 16f877 - MikroC , with receiver and transmitter of IR

here i use PWM in pic to generate frequency to the transmitter , that's code

PWM1_Init(38000);
PWM1_Set_Duty(255);
PWM1_Start();

that's mean ,,, i want to generate a permanently signal with 35KHz -IR

but here in receiver ,, how it will detect the beam if it cutted of no !!!

i searched and i found many protocols and decoding bits.....
but i think that my projects is more simple ,, just IR beam if cutted , the receiver give a flag to PIC to execute any other function.


any one here can help me !!

greatings

 

[hexreader]

i want to generate a permanently signal with 35KHz -IR

Do you mean 38kHz IR?

What receiver are you using?

The 3-pin receiver chips that I know of will not work with steady 38kHz signal. They need modulation of (typically) around 1 or 2 kHz.

something like:

1 Send 38kHz for 500us
2 Send nothing for 500us
3 go to step 1