detecting rising edge

Hello.

I have an Enitiy that have in siraial input ,clk and output bus.

i need to count time between falling edge of my input until rising edge of the same input but all this needs to be synchronize to main cl k.
Thx

put a double syncroniser (flop1 ,flop2)and connect the output of this to a 3 rd flip flop...
now use (a and ~b) logic at the output of flops 2 and 3
where a and b are outputs of flops 2 and 3
...
all the flops are synconosed to mainclk...

iliya24 said:

Hello.

I have an Enitiy that have in siraial input ,clk and output bus.

i need to count time between falling edge of my input until rising edge of the same input but all this needs to be synchronize to main cl k.
Thx

Click to expand...

Thx, could u help me some more i am a new to all this i cant realy undersatn how 3 flip lops will help me to detected risiing ede and falling edge i need to detected both but on the same input .
thx.

a exor b can detect both rise and fall edge
a and ~b detects rise edge
~a and b detects fall edge
please draw the circuit and verify by drawing waveforms

iliya24 said:

Thx, could u help me some more i am a new to all this i cant realy undersatn how 3 flip lops will help me to detected risiing ede and falling edge i need to detected both but on the same input .
thx.

Click to expand...

- - - Updated - - -

a xor b can detect both rise and fall edge
a and ~b detects rise edge
~a and b detects fall edge
please draw the circuit and verify by drawing waveforms

iliya24 said:

Thx, could u help me some more i am a new to all this i cant realy undersatn how 3 flip lops will help me to detected risiing ede and falling edge i need to detected both but on the same input .
thx.

Click to expand...

thx i will do it.