Inputs and Outputs

I'm trying to use the Cirrus Logic Audio Card and RPi2 in a Software Defined Radio application. Specifically the Softrock RXTX Ensemble: WB5RVZ - Home Page

I was hoping I could use this card to do both RX and TX, but it's not clear how I can present the various inputs and outputs to the SDR software. I'm working with Quisk right now (apt-get install quisk).

Normally I would present an audio device as hw:0 and hw:1 and so on. This card only has hw:sndrpiwsp and I have to use the various scripts to activate inputs/outputs.

I only need to record and playback from one input and output at a time, but the trick is helping the software to switch between inputs and outputs when I push the transmit button. Right now taking the Record_from_lineIn audio processing that in Quisk and then having the output from Quisk go to the headphone jack works like a champ. I have to manually run the scripts and change to Record_from_DMIC and Playback_to_Lineout.sh which is rather clumsy.

So anyone know if I can use something more specific than a generic hw:sndrpiwsp device?

0 clem57 over 10 years ago

build python script like this pseudocode:
loop forever until keyboard interrupt.
test transmit button
run transmit script for x time.
else
run receive script for x time.
loop repeat
Cancel
Vote Up 0 Vote Down

Sign in to reply

Verify Answer

Cancel
0 e14 Contributor over 10 years ago in reply to clem57

Quisk is actually python code so I suppose I could have it set the sound card i/o on the fly. But that is no solution for other tools. I need to switch inputs and outputs within a few milliseconds or it won't be practical.
Cancel
Vote Up 0 Vote Down

Sign in to reply

Verify Answer

Cancel
0 clem57 over 10 years ago in reply to e14 Contributor

You need to assign higher priority to task/process running on Pi to make that happen under Linux!
Clem
Cancel
Vote Up 0 Vote Down

Sign in to reply

Verify Answer

Cancel
0 gonesurfing over 10 years ago

Late reply, but I'm using Quisk with a softrock RXTX ensemble also. However I'm sending the IQ audio over the network with pulseaudio. Pulseaudio is playing nicely with the Wolfson card for both line in and line out.

I'm using usbsoftrock to key the radio. Here's some info under my old call sign.

https://km4dsj.wordpress.com/
Cancel
Vote Up 0 Vote Down

Sign in to reply

Verify Answer

Cancel