Okay, thanks for the help, we'll start looking into it and maybe purchase a beagle board for evaluation.
By the way, there doesn't seem to be a link to the patch in 1) (unless I am slow and this is some dark humor ;)
On Thu, Jan 15, 2009 at 10:37 PM, Philip Balister
<address@hidden> wrote:
> Hi, has anyone had success porting GNU Radio to Gumstix? I would like to
> install it on the Overo Earth board (OMAP 3503 with ARM Cortex-A8) if
> possible. I searched around but couldn't find much written about this. It
> would nice to connect Gumstix to the USRP at least.
At this years SDR Forum I did a demo of Gnu Radio running on the
Beagle Board (http://www.beagleboard.org). The Beagle Board is fairly
close to the gumstix overo product line.
You should be able to build gnuradio radio for the overo via
OpenEmbedded. I haven't had time to try this, but I plan to in
February, if I can get some free time (as in no other paying work).
The list of issues at the moment:
1) GNU Radio is obsessed with floating point :) For my demo, I
converted one of the FIR filters to use the NEON co-processor. GCC is
not real good at genereating good code for NEON, so I used GCC inline
assembly. The patch is here :
2) The USRP code depends on knowing internal structures of
libusb-0.12. Angstrom is using the libusb-1.0 code which breaks the
USRP. I can build Angstrom with libusb-01.12, but it is a "nuisance".
We need to work though this issue anyway for GNU Radio to run as
distros convert to libusb-1.0 anyway.
3) The Overos have an EHCI host, which is the best place to attach the
USRP, but you will need a hardware mod to make this interface work.
Expect an email from Gumstix about this. In the past, I've had some
success on the MUSB port also. This needs work.
4) We need to add support in GNU Radio based on the patch in 1.
5) I can run bits of "make check" by mounting the OE build dir via
NFS, but there are some libtool issues to resolve.
6) Convert more floating point to use NEON.
7) Add better support to GNU Radio for suing data types other than
float. (Maybe not as critical for the OMAP3, but there are some
interesting platforms that would benefit from this)
8) Future Gumstix products may use the OMAP3 with the DSP. (The Beagle
already has the DSP) Moving algorithms to the DSP should be
interesting. This DSP is not floating point, see 7.
Hopefully, this gives people an idea of how to migrate GNU Radio off
"big iron" onto smaller, lower power, hardware. I'm glad to answer
specific questions and do plan to work on OMAP3 support as I have
time.
Philip