Re: [Discuss-gnuradio] Make USRP run w/o SW intervention

[Marcus D. Leech]

On 09/27/2011 06:04 PM, Philip Balister wrote:
> I see a couple of possibilities;
>
> 1) Use a microblaze in the fpga to control the spi bus and other 
> control functions. (It may already use a microblaze, so update the 
> code to do this internally, instead of taking commands from ethernet)
There's a ZPU in the FPGA--it handles some of the protocol and low-speed 
interfacing "goop" in the normal firmware/FPGA load.
  But the general "model" is that the FPGA/firmware is "dumb".  It 
simply provides a fairly generic "peek and poke" interface over
  the Ethernet, with all the "smarts" in the host code.  I think part 
of the motivation for this is that it's easier to modify host code
  for minor performance tweaks, etc, than doing it in the firmware/FPGA 
code.   But one could certainly enhance the small amount
  of firmware that runs on the ZPU to handle all the device register 
initialization, etc.

--
Marcus Leech
Principal Investigator
Shirleys Bay Radio Astronomy Consortium
http://www.sbrac.org