Re: [Discuss-gnuradio] SDCC 2.9 versus 3.0

[Marcus D. Leech]

> What is SDCC used for? I just want to sure that I understand this correctly. I 
> think it's used to compile the firmware that runs on the Xilinx MicroBlaze CPU 
> on the FPGA inside the USRP, USRP2, and USRP N200/N210. (all USRPs have FPGAs 
> inside with Xilinx MicroBlaze CPUs on them) Normally, you don't need to do 
> this. Users download the latest binary firmware image from the Ettus website 
> and burn it to the SD memory card (USRP2) or flash memory (USRP N200/N210) and 
> run it. You'd only really need SDCC if you want to modify the firmware and run 
> a customized version of it.
>
> Could you please correct me where I'm wrong/inaccurate?
>
> Thanks.
You only need SDCC (or the equivalent ZPU version of GCC for USRP2/N2xx 
under UHD) if you want to compile custom firmware.

SDCC is used *only* for the USRP1, which uses an 8051-variant called an 
FX2, which has a built-in hardware USB implementation that
  "goes real fast".

Normally, you simply use the pre-compiled firmware and FPGA images that 
you get from Ettus' website.

In the early days I think Matt didn't bother distributing the firmware 
images, since you could always compile them from the source code
  that came with Gnu Radio, using the SDCC 2.X compiler.  With the 
advent of binary-only packages for Gnu Radio, there had to be
  a mechanism for the firmware images to be made available to you.

So, the firmware and fpga images are now always available from the Ettus 
website.   The matching source-code is part of a standard
  UHD "git" checkout--but again, you can only rebuild them yourself if 
you have the correct toolchains.  So the overwhelming majority
  of users just use the pre-built images.  Users who want to do their 
own custom firmware and FPGA will need to acquire the appropriate
  toolchain, and compile.

My "build-gnuradio" script downloads the latest matching firmware 
images, and installs them in the "right place" 
(/usr/local/share/uhd/images),
  along with fetching/building the latest UHD and GnuRadio.


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