Re: AW: AW: USRP, GPIO toggling and Gnuradio

[Marcus D. Leech]

On 2021-09-10 12:08 p.m., Dobler, Anton wrote:

Is there any alternative to the standard GPIO UHD interface, that allows me the desired speed and is this issue I see related to gnuradio and its scheduler or rather to the UHD API for the GPIOs?​

BR,

Anton​

    Every GPIO state transition requires a transaction across your
    network interface, and then into the FPGA GPIO logic.  That's the
    absolute upper limit on
      toggling the GPIOs from the host.
    
    You can test how fast you can make this go with a "raw" UHD C++
    program.  Once you've established how fast it can potentially go,
    then you start
      evaluating how to approach this latency with GR.  Right now, the
    waters are very muddy, and I am not the one to comment on GR
    latencies, etc.

---

Von: Marcus D. Leech <patchvonbraun@gmail.com>
Gesendet: Freitag, 10. September 2021 18:04
An: Dobler, Anton; discuss-gnuradio@gnu.org
Betreff: Re: AW: USRP, GPIO toggling and Gnuradio

 

On 2021-09-10 11:54 a.m., Dobler, Anton wrote:

I am extracting the package rate of a receive signal using a rather complex GRC flowgraph, i.e. I am detecting the preamble of a receive signal and generate a clock from here. This clock signal period is within the range of 100us - 1ms.

Toggling GPIOs using the standard GPIO interface for signals this fast is likely not going to be very speedy.

The GR experts will have to answer your other questions.