On Mon, Aug 11, 2008 at 9:45 AM, Philip Balister <[EMAIL PROTECTED]> wrote:
> While Chris is focusing on the hardware to connect USRP daughterboards to
> the Beagle Board, I am thinking about software and whatever you call the
> FPGA definition (no, I will not get drawn into the hardware/software
> argument).
>
> GNU Radio appears to be the most popular open source SDR package. It is
> heavily oriented toward to desktop PC class machines, however since the
> beagle has floating point capability, this is not as much of a problem as it
> would be for FPU-less machines. Things that would be good additions to GNU
> Radio:
>
> 1) NEON implementations of the core signal processing code. Eric has already
> shown how this would be structured with his Altivec work.
Good idea. I haven't written assembly in a while, but it sounds fun.
Is there an ARM ARM for NEON instructions?
> 2) Create equivalent of gr-usrp to get data from the FPGA.
This will depend on the interface used for the expansion connector,
but should be relatively straight forward. It should be limited to
the libusb calls being replaced to beagleboard specific interface
calls. Right?
> 3) fftw that can use NEON.
Does FFTW support ARM/NEON? This might be a bit more difficult to
achieve, especially since I doubt anyone on the list has FFTW hacking
experience. :(
> The Beagle expansion connector supports several different interfaces. We
> need to develop FPGA firmware that can send/receive data and commands via
> these interfaces. It would be good to create some sample implementations and
> see which interfaces are better than others. I am looking into purchasing a
> dev board and an expansion board to test the beagle hardware interfaces. Any
> help here would be great :) Also, I am hopeful the pins on the FPGA can
> direct connect to the Beagle Board pins. It would be nice if someone who was
> good at this could check :)
You have to make sure the pins on the bank of the FPGA you're going to
connect to are the same logic level as the OMAP. Do you know if those
OMAP pins are 1.8v or 2.5v? Do you know which board you want to try
to connect it to? Either way, it should be pretty quick to verify
they should be compatible at the voltage level.
> I also did a real quick skim of SDR-Shell + dttsp this morning. This may be
> another way to use the hw.
>
> Philip
>
> PS: Anyone have any suggestions for a "cheap" logic analyzer from ebay,
> suitable for working with a cyclone III?
I've heard good reviews of this:
http://www.pctestinstruments.com/
500MHz sampling, 34 channels and $389 isn't too bad.
Brian
