Thanks for your description of the cross compiling. Excellent example.
We’re working on an “Event Capture” code and would like to use as wide
a bandwidth as possible, but only rarely capture data (once every few
minutes.)
So on the PlutoSDR we’d like 20 MHz samples, but somehow transfer
the data to the host, at a very low data rate. We already have a
design that does this external to the SDR, on a Raspberry Pi 4.
(But it has a GUI we’d have to remove.) The maximum data
rate the Pi, with PlutoSDR will support is 4.5 MHz due to
dropped packets in transmission to the Pi.
With a 6 MHz bandwidth Airspy and a raspberry pi we can
easily capture noise in the device, when the noise level is
set sufficiently low.
Our software centers the event in the time window.
We’d like to have this run entirely inside a PlutoSDR, but without the GUI.
One problem we’ve had is that installing custom firmware disables Gnuradio compatibility.
We can probably live with this, but it would be nice if we could have the test Gnuradio internal
to the PlutoSdr not disable the use for communication to the host.
The science reason for this is to detect radio transient events. We have 4 horns that are all looking
for cosmic ray flashes, created when ultra-high-energy cosmic rays hits the earths atmosphere.
These flashes cover a small area, about 100 meters in diameter. So a few horn telescopes
in a small area have a unique look at ultra high energy cosmic rays, depending on their location.
We’ve seen long (10 to 50 micro-second) flashes and short, < 2 microsecond duration flashes.
Pictures show these flashes. This is all done inside Gnuradio.
The pictures show the 4 horns, plus two events. There are two plots of each
event, one for the entire time range recorded and the other zooming in on the event.
The time tags are hours minutes seconds and after the _ milliseconds, i.e. HHMMSS_micro.
We think these are outside the electronics because for the long events all 4 horns have
long events, and for short, all 4 horns see short events. We’d like faster time
sampling, up to 40 Mega samples per second. We also need better time, but
that’s a different problem.
We have not been able to get better timing accuracy on the Pis
than about +/- 30 milliseconds. I now think this is due to circular buffers in Gnuradio.
(still to be determined).
So, to conclude this long email, it would be fantastic to learn how to use Buildroot to figure out how
to program Gnuradio on the PlutoSDR. There are some fantastic applications!
Best regards
Glen
On Jun 4, 2020, at 3:49 AM, jean-michel.friedt@femto-st.fr wrote:
I have followed
https://bootlin.com/blog/building-a-linux-system-for-the-stm32mp1-basic-system/
to generate the STM32MP157 cross-compilation framework. Once the Buildroot
environment is functional, you can follow
https://github.com/oscimp/PlutoSDR/tree/master/doc
to add GNU Radio support including libuhd/B2xx support.
At the moment we are stuck with rpmsg communication as we would like to use
the M4 as pre-processor for the datastream feeding a GNU Radio source, but that
is beyond your scope I believe.
JM
--
JM Friedt, FEMTO-ST Time & Frequency/SENSeOR, 26 rue de l'Epitaphe,
25000 Besancon, France
June 4, 2020 9:44 AM, "Henrique Do Carmo Miranda" <hmiranda@alumni.stanford.edu> wrote:Hi all,
I would like to install and test GnuRadio on the STM32MP157C-EV1 processor evaluation board for the
STM32MP1 processor
(https://www.st.com/content/st_com/en/products/evaluation-tools/product-evaluation-tools/mcu-mpu-eva
-tools/stm32-mcu-mpu-eval-tools/stm32-eval-boards/stm32mp157c-ev1.html), along with the USRP
B205mini.
Do any of you know if compiling and installing GNURadio on this platform has been attempted before,
and if so do you have any pointers that can guide me through that process - could not find any info
on it (just wondering if compiled images might be out there)?
If not, setting up a Linux machine with all the tools to cross-compile GNUradio for the STM32MP1
target would be the way to go here?
Would https://wiki.gnuradio.org/index.php/Embedded_Development_with_GNU_Radio be the best guide to
this process?
Thanks much for your help,
Henrique