Nothing about CNC, but...

[satanicoo]

I have asked this on a electronic forum, and no one could help me too, maybe here you guys can be a bit more handy!
I am trying to do a simple serial-to-serial shift register, with D-flip-flops, just as simple as This.



And i am using a 74HC374 IC, Octal D-Type flip-flops.
This is my diagram:





What am i doing Wrong?

I ask this because, when i set LOAD to 1 (5 volts), and give a clock to the circuit, all the outputs of the used flip-flpos becomes 1, it never loads only 1 bit!
Yes i have made sure that, at the clock input pin, only one clock is submited, so no several clocks could be imputed with a push of a button.
Q0, Q1 and Q2 are all connected to resisted LED's to check their state.

Why? i can't understand !

[nophead00]

Sure looks like you are giving it multiple clocks. How have you ensured that you only give one at a time?

[satanicoo]

At the clock input, i have hadded a 1k resistor to ground, and a huge cap.
i connect clock to vcc trought a 500 ohm, and it takes a bit for the LEDs to lit up , so that it absorbs the noise when i connect the wire.

Still a no go, when it happens, all of them lit up

[_Eduardo_]

What is the clock source?
If it is a pushbutton then is bouncing. ==> need a debounce circuit (cap + schmitt trigger)

[nophead00]

The huge cap will cause a slow rising edge, which edge triggered logic circuits don't like. This may cause each d-type to clock at a slight different time as each will have a very slightly different threshold for switching from 0 to 1. To make a shift register they must all switch together.

You need to use one of the circuits here :- http://www.elexp.com/t_bounc.htm

Also you should have a decoupling capacitor between VCC and ground close to the chip. 100nF should be fine.

[satanicoo]

Back

Well i pick up my lazy a$$ and went to buy a 555 IC and some pieces to make a regulated clocker.
I mounted them all and...

...it works.

Thanks all, i feel like an idiot but at least it works now and i have learned something