[Discuss-gnuradio] Issues with USRP2 firmware

[Matthias Wilhelm]

Hi,

I'm currently working on a few changes to the FPGA image, but I ran into some 
strange issues that I want to bring up here. 

1. It seems that txrx_edk10.1_3.3git-645-gb811e87.bin from the binary builds in 
http://gnuradio.org/releases/usrp2-bin/trunk/ is not properly working with both 
the latest provided u2_rev3.bin as well as a custom build one from the latest 
git version of the gnuradio firmware. The hardware boots up, the LEDs flash 
correctly, and the find_usrp2 also works, but the usrp2_fft.py seems to work at 
first, but the samples provided seem like noise, although in normal operation 
signals are visible. Additionally, switching the channel seems to work as well, 
but there is just different levels of noise everywhere. When changing the 
decimation value from 16 to 4, the fft (and probably the hardware) hangs. 
Revision txrx_edk10.1_3.3git-594-g02616cf8.bin seems to work correctly. 
Either I'm doing it wrong, or there are some issues with the firmware. I tried 
this with the XCVR2450 board. 

2. The Xilinx tools in version 11.1 are without patches not able to generate 
the bitstream, even make proj failed. The build also fails because it needs 
more RAM than available with a self-made project. With the latest service pack 
(sp 5) the software is able to produce a .bin file, but not even the LEDs flash 
with this version. There are a lot of  warnings, so I cannot tell what the 
problem is, but it seems that successful compilation is not enough to make it 
work. I made an .ise file with make proj and imported it into ISE, so maybe 
some vital information got lost in the process, but since the logic is given i 
cant understand how something could go wrong here. 10.1 sp3 works correctly as 
expected. 
I'm willing to play around with 11.1 a bit more, so if you have some ideas on 
how to debug this, I can invest some time into this. 

Matthias