Dear ALL,

I am building a heart rate monitor.I am using a high intensity led and a ldr to detect the movement of blood.

I fed this signal to a schmidtt trigger,which gives me square signals.With this signals i want to measure the frequency and convert it to beats per minute.I am using the 8031 and a 12Mhz crystal.Please help me with the code or just the flow chart that indicates the flow o signals.

PS:I have completed the hardware.

Thanks in advance,
Hatem Zakaria