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xczu4ev_0 PL Power Status OFF, cannot connect PL TAP. Check POR_B signal

Started by logmaster, July 19, 2023, 01:31:26 PM

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Hello everyone,

I am currently facing a problem with Vivado 2019.2, Petalinux 2019.2 and TE0803 on the TEBF0808 carrier board:

After successfully booting into embedded Linux image generated by Petalinux 2019.2 from the project provided in the StarterKit for TE0803, I would like to connect to the board through Vivado Hardware Manager and observe some data on the ILAs.
The problem that I am facing is that Vivado cannot open the ILAs menu and shows this error:

xczu4ev_0 PL Power Status OFF, cannot connect PL TAP. Check POR_B signal.

The boot mode is set to SD card.
The carrier board is not powered through the ATX connecter, but from a separate 12V power supply

The weird thing is that if I boot from a different SD card, that has a very similar image, generated from the same project, but with some minor differences in the PL design, Vivado recognizes that the PL is on and is programmed. The changes on this SD card were only done to the custom IPs that we are developing and not the Zynqmp PS.

What could be an issue here? Could it be some setting in Petalinux or the PL design?

Thank you!

Best regards


in general PS-PL CLKs depends on your FSBL which depends on your XSA which is exported from your vivado project. In case FSBL is not correct, maybe some PS-PL CLKs are missing, which are normally needed for your ILA core. Also Linux device tree must be correct. In case Linux was generaded with xsa where PS-PL CLKs was deactivated, than it will deactivate these CLKs again.....

Warning"xczu4ev_0 PL Power Status OFF, cannot connect PL TAP. Check POR_B signal." will happens in Case PS is not correctly initilised and boot mode is not JTAG only. Or you has a power problem...
We have some reference designs online, which contains VIO cores. You can test prebuilt binaries for your variant and System should boot Linux and you see some VIO Core in Vivado HW Manager. Can you try out these binaries?


Hello everyone,

for whom ever who is facing issue at the moment, I found an explanation that describes why this warning appears. On my side this warning appears only if the image has secure boot features enabled. That means encryption and/or authentication. When those features are disabled, the Vivado Hardware Manager and ILAs work fine.

If you would like to test your hardware design with the Hardware Manager and use secure boot features, make sure to first do your testing on a non secure image and afterwards enable security.

Thank you!