Making a Gnuradio Settings block
<p>We're going to be using Gnuradio to stream in data from a radio peripheral. In addition, we have another peripheral that is part of the system which control programatically. I have a basic C program to do the controls.</p>

<p>I'd like to be able to implement this in GNUradio, but I dont' know what the best way to do this is. I've seen that you can make blocks, so I was thinking I could make a sink block, have a constant feed into that, and have the constant's value defined by some control like a WX slider. </p>

<p>It would take a needless part out of this if I could remove the constant block and just have the variable assigned to the WX slider directly be assigned to the control block, but then there would be no input. Can you make an inputless and outputless block that just runs some program or subroutine?</p>

<p>Also, when doing a basic test to see if this was feasible, I used a slider to a constant source to a WX scope plot. There seems to be a lag or delay between putting in an option and seeing the result show up on the plot. Is there a more efficient way to do this that will reduce that lag? Or is the lag just becasue my computer is slow?</p>