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Sample & Hold oddity

Posted: Fri Apr 12, 2013 10:38 pm
by matti
If i connect a string to sample and holds trigger input and after that to it's data input it would be logical that it triggers before new data is received, and won't pass the new data until next trigger.

Should therefor work as a "one sample delay" type of thing.

But it won't :(
No matter what order things are connected the change moves along.

Re: Sample & Hold oddity

Posted: Sat Apr 13, 2013 12:07 am
by MyCo
Have a look in the User Guide, on page 87 "Triggered Data - How it Works", there is exactly explained, why this happens.

Re: Sample & Hold oddity

Posted: Sat Apr 13, 2013 9:32 am
by matti
MyCo wrote:Have a look in the User Guide, on page 87 "Triggered Data - How it Works", there is exactly explained, why this happens.


Umm. No, it doesn't mention this phenomenon at all. It explains the way triggers used to work in SM, and the way I'm presuming they would work now.. but they don't. :?

Just to add. I do understand the logic of how the sample&hold now works. I just think it's not logical :D
And i think it didn't do this before... can't be 100% sure, and can't be bothered to install SM to confirm.
Maybe I'll leave it at that :geek:

Re: Sample & Hold oddity

Posted: Sat Apr 13, 2013 10:25 am
by MyCo
matti wrote:Umm. No, it doesn't mention this phenomenon at all.

In the graphic, it is exactly explained... there is no way to make that clearer.

matti wrote:I just think it's not logical :D

Well, the S&H wasn't even made for that what you do.

matti wrote:And i think it didn't do this before...

It's doing that atleast since I work with S|M... which is 2005

I try to explain it for your problem:
1. When you type something in, the output value of the string primitive changes.
2. The string primitive sends out a trigger to the trigger input of the S&H, to notifiy that
3. The S&H has now to update its state, so it requests the current value of all inputs... so it asks the string primitive: "tell me your value".
3. The string primitive tells the S&H now its output value (which is the new string)
4. The S&H does it's job with the new value, and pass it to the output. And all above steps go on for the next connected items.

Re: Sample & Hold oddity

Posted: Sat Apr 13, 2013 11:32 am
by billv
As Myco suggests, there's nothing odd here Matti.
Anything plugged in to the input gets told" STOP. Wait here and do nothing, untill a trigger comes".
So thinking that,
matti wrote:it would be logical that it triggers before new data is received

sort of defeats the whole purpose of the S+H in the first place.

It also prevents backward triggers....

Try Trogs "Trigger" tutorial, where he has gone to great lengths to explain all this
http://synthmaker.co.uk/forum/viewtopic.php?f=7&t=10693&st=0&sk=t&sd=a

Re: Sample & Hold oddity

Posted: Sat Apr 13, 2013 12:07 pm
by matti
So it's not "Sample&Hold" in a sense to what Sample&Hold really means..
It's "Fetch earlier results & Hold".

I can live with that :D