Re: [Discuss-gnuradio] transmitter switching (PTT switches, microphones, Vox)

[Daniel Pocock]

On 10/01/16 18:45, Marcus Müller wrote:
> Hi Daniel,
> 
> USB sound devices with mute/unmute buttons usually have a USB endpoint
> that enumerates as Human Interface Device; in that way, they are simply
> keyboards with a highly limited set of keys.
> Now, I'm not aware of any GNU Radio OOT that is able to capture such
> keyboard events, but that doesn't necessarily mean something like that
> doesn't exist. Problem is that registering a listener for key events is
> OS-specific. Maybe one can find something portable based on SDL?
> 
> Easiest case I can think of: one could simply imagine configuring your
> Window/Session manager to execute a specific program on the matching key
> press, which in turn might, for example, simply send a UDP packet or
> something similar to a GNU Radio application, where a pass/drop block
> would change its operational state based on that. Or maybe a multiplier
> that changes between factors of 0 and 1, or something similar.
> 
> The point here is that what should happen when such an event occurs
> depends on what your flow graph looks like, and what you want the event
> to manipulate.
> 


Looking in Google, I found one example using some other Python library
to get joystick PTT button events:

https://github.com/jmalsbury/oa/blob/master/gr-openavionics/apps/joystick_101.py

and there are other Python libraries too:

http://www.pygame.org/docs/ref/joystick.html

Is this considered the ideal way to use a joystick button for PTT?  Or
would it be considered more suitable to have a flowgraph component that
people can manipulate from GRC?

Can anybody comment on any other aspects of PTT for a half-duplex flow
graph?

One of the reasons I'm asking about this is that if some coding is
needed to make new components for this, it could be one of the tasks for
a GSoC applicant to work on.

Regards,

Daniel