Problem with Using integrated logic analyzer (ILA) for Debugging with PYNQ

Hi all,

I am using pynq with a Jupyter notebook environment with a RFSoC ZCU111 board. I want to debug an overlay created by myself using ILA core in Vivado. I have inserted the ILA core into the design. Then I use the overlay class in pynq to program the device.
The problem that I am facing is that when I open the hardware manager in Vivado and connect to the board using the Jtag interface, I lose my Ethernet connection to the board and I cannot run the program anymore in Jupuyter notebook.
Any suggestion to help me out?


Maybe add VIO so you can control the design?

hi, rock,

Is it expected to loose Ethernet connection once use of ILA debugging via the JTAG interface in Vivado on PYNQ as you know?


Why does that happen?

I have the same problem. May be related to CPU Idle - see To fix this seems to require a recompile of the board PYNQ boot image :frowning:

OK, it looks like it’s possible to fix this without recompiling PYNQ. Add a new file “uEnv.txt” to the SD card with the following line:
bootargs=root=/dev/mmcblk0p2 rw earlyprintk rootfstype=ext4 rootwait devtmpfs.mount=1 uio_pdrv_genirq.of_id="generic-uio" clk_ignore_unused

This adds to the rest of the default bootargs found from

Now the hardware manager seems to work and so does the Jupyter Notebook interface.

When you boot, you should see “Loaded environment from uEnv.txt” in the uBoot messages on the serial port.

Some info from:



Thanks for the info.
In which directory should I add this file?