[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Discuss-gnuradio] Change the RX frequency of USRP Source using a ta
From: |
Marcus Müller |
Subject: |
Re: [Discuss-gnuradio] Change the RX frequency of USRP Source using a tag |
Date: |
Sat, 18 Mar 2017 20:43:39 +0100 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 |
Hi Damindra,
On 18.03.2017 20:31, Damindra Bandara wrote:
> Hi,
>
> I was able to add a tag (tx_freq) and change the the frequency of USRP
> sink successfully. I want to do the same thing for USRP source. Since
> source doesn't take any input I was wondering how to do this.
It does! It has a message port, which accept commands. You can enable
the display of that port in the Block options, if you're designing with GRC.
>
> I tried with message strobe and it worked, but I need to change the
> frequency based on some external event. When that event happens I want
> to add a tag to trigger the frequency change.
ah, you already found that :)
Tags are things that are attached to a sample flow – the source of a
sample stream can add a tag, but you can't add tags and make the source
react to that – that'd be inversion of causality.
so, I think what you should do is write some class that sends a message
as soon as the event happens.
Best regards,
Marcus