USRP2 and UHD 3.8.3

Dear USRP2 users,

(Note: this does not affect N2x0, or any other device! Only USRP2,
with the SD-Card).

The latest release (3.8.3) has an issue where UHD won’t let you use
USRP2s. Apologies for missing that during testing and RC phases. Latest
maint (and master) contain a fix for this, and future releases will also

If you need to run USRP 2 with a stable release, we recommend 3.8.2,
although the USRP2 code (both host- and FPGA-side) has not changed in a
long time, so older versions will also work.

So, what happened? Our latest release actually had some changes for
N2x0, mostly related to UBX fixes. As a consequence, we updated the N2x0
FPGA images, and increased the compat number. On USRP2, nothing was
changed at all, but due to shared host driver code, UHD is looking for
the same compat number on both devices. Since we didn’t touch USRP2
specifically, it fell through in our testing.

This fix simply provides separate compat numbers for USRP2 and N2x0. The
actual FPGA image for USRP2 never changed, so you don’t need to burn the
SD card for this. If you already did, that’s also fine – the current
FPGA images for USRP2 are legit.



The source code for both USRP2 and N210 was updated at the same commit
with the new FPGA compat number
Hoever because nothing changed functionally on USRP2 someone forgot to
re-build USRP2 images for inclusion in the updated binary image package.
You are not affected because you build your FPGA from sourceit only
affects (typical) users who get pre-built FPGA’s from Ettus.


Is a patch available to fix the problem?