UHD Announcement - August 16th 2010

Hello list,

I have pushed up new host code to the repo, and uploaded new images. So
what new since the last announcement?

  1. Subdev specification:

A daughterboard may have more than one rf pathway on it. These pathways,
combined with tuning and gain elements make up what is called a
subdevice. The basic RX has 3 subdevices: 2 real and 1 complex.

A subdevice specification allows you to specify which subdevices you
want to use, and may be specified with a markup string

The subdevice parameter is already part of the gr-uhd grc wrapper

There is not much advantage in messing with subdevices in the USRP2, but
when USRP1 support comes (multiple daughterboard and dual DDC) this will
become very important.

  1. Async messages:

Transmit related errors (such as an underflow) can now be reported back
to the host. One can simply read async messages out of the queue and act
accordingly. The messages carry an event code and the timestamp of the



  1. DBSRX:

DBSRX support is now available (it has been mentioned a few times but
not formally announced). The UHD-based modification instructions can be
found here:

  1. Image packages:

The fine details are still being worked out, but the idea is to give
users installable packages with pre-compiled firmware and fpga images.
The installer will place the images in the uhd images directory, and the
uhd will find the images at runtime. This will be useful for the coming
UHD-USRP1 support.


For USRP2, one would need to download and upack the tarball/zip and use
the card burner utility to load the images onto the sd card.

Currently we offer zips, tarballs, debs, rpms. Eventually, Windows NSIS,
and Macintosh will be built. The possibilities can be found here: