TTL (PWM) Laser head and Mesa 7i76

Ok so I should remove the 12V connection and the change back the w8 pin? or should I connect 5V to the connections where I have now connected the 12V on the BOB

Do not change W8

The BOB has a 5V power connection, you must supply that with 5V power
(This is often labeled PC5V)

You only need the 12V connection on the BOB if you wish to use its
input pins (P10,P11,P12,P13,P15)

There is 2 PC5V, I guess any will do. 

the 12V then dont do any damage if it stays ?

 

W8 _must_ be down

The 12V wont hurt but is not needed unless you want to use the BOB inputs

Either PC5V will work

If you are driving a mechanical relay, the relay coil needs a flyback diode
_VERIFY_ the flyback diode polarity first before connecting it to the 7I96
or you will likely damage the 7I96

I have not connected the relay yet.
Everything seams to work now

Last question for now.
what is the interval for min and max power?
I usually have 0-255 is that still the case here?

If you ever are close to Uppsala or Stockholm Sweden a few beers at the least is on me!

Full scale is set in this line:

setp   hm2_7i96.0.pwmgen.00.scale 100
 
so

setp   hm2_7i96.0.pwmgen.00.scale 255

should do what you want