[Discuss-gnuradio] Porting new hardware to GNURadio

[Getz, Robin]

Hi.

Sorry for what might appear as a commercial at first - but I do have some real 
questions at the end - I'll try to the description short.

We have developed a new RF learning platform [1] on a standard FMC card [2] 
(meets the electrical requirements, not the mechanical - it's too long) - 
which can connect to nearly any recent Xilinx development system, that we 
started showing at X-Fest[3] yesterday.

The advantage of this, vs some existing platforms is bandwidth. The DAC is a 
16-Bit, 1200 MSPS (limited on this platform to 1GSPS, due to the clock chip 
we used), and the ADC is 14-Bit, 250 MSPS. The RF side includes a 400 MHz to 
6 GHz Quadrature Modulator/Demodulator, separate Tx and Rx LO Synthesisers  
(35MHz to 4400MHz), and fixed gain on the Tx side, and a Variable Gain on the 
Rx Side. It's clocking can handle multiple boards attached to the same FPGA 
(for MIMO), and can sync to a 1 pps (from GPS, or IEEE 1588) to sync many, 
many, many boards together.

The demo we are showing at X-Fest is the FMComms board, attached to a Xilinx 
ML605 FPGA, which runs Linux on Microblaze - playing a tone (Xilinx DDS) out 
the DAC, modulating that up to 2.4 GHz, sending it out the antenna, receiving 
it on the same board, demodulating it (at 2.4GHz), passing it through the 
VGA, to the ADC, were we capture the samples (into DDR), passing the data to 
GNU plot to create a png, and then passing the png to a web server, so it can 
be displayed on an external client across the network.

We have ported this to the Series 7 platforms - KC705, and others, and are in 
process finishing the port to Zynq[4] - for the standard Xilinx ZC702 
platform [5] and the newly announced Zed[6]. This (I think) is where things 
get a little interesting. Microblaze running Linux is a little pokey - Zynq 
on the otherhand - is a dual ARM Cortex A9, running at 800MHz each, plus FPGA 
fabric - which allows some serious horsepower. This is a kit (Zynq+FMComms) 
that Avnet plans on selling [7].


Which brings me to the question:

We already have Linux IIO drivers[8] for all the parts on the board (including 
the ADCs[9] and DACs[10]), and are just trying to determine how (if at all) 
this fits within the GNU Radio framework.

When I looked at things (which wasn't very long) - I didn't see much in terms 
of native / real time connections to a platform which was running Linux 
(PCIe, other other bus). Did I miss something?


Thanks in advance

-Robin

Just to be fair - others have done the same type of FMC Card [11] - the 
advantage we have is gobs of channel bandwidth - enough to sample all of 
bluetooth without doing any hopping at all.

[1] http://wiki.analog.com/resources/fpga/xilinx/fmc/ad-fmcomms1-ebz
[2] http://www.vita.com/fmc.html
[3] https://www.weboom.com/avnet2012/
[4] http://www.xilinx.com/products/silicon-devices/epp/zynq-7000/index.htm
[5] http://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC702-G.htm
[6] http://www.zedboard.org/
[7] 
http://www.em.avnet.com/en-us/design/drc/Pages/Analog-Devices-Zynq-Software-Defined-Radio-Kit.aspx
[8] http://wiki.analog.com/software/linux/docs/iio/iio
[9] 
https://github.com/mhennerich/linux/blob/fa8fc592243c82c0ddaa43f51be10e2123e1fa9b/drivers/staging/iio/adc/cf_ad9467_core.c
[10] 
https://github.com/mhennerich/linux/blob/fa8fc592243c82c0ddaa43f51be10e2123e1fa9b/drivers/staging/iio/frequency/ad9122.c
[11] http://www.4dsp.com/FMC30RF.php