Zedboard printing garbage/junk over UART

[rward]

Hello,

I have been working through some basic examples on the Zedboard, i.e. creating a simple PL fabric to switch an LED upon a button press. The board will program fine, and the system will work (i.e. LEDs and buttons work fine), however, whenever it prints something to the terminal, it appears as junk. I have a cable plugged into the J17 (prog) port and the J14 (UART) port. I have tried every baud rate possible, I understand that the standard is 115200, however no baud rate works (have tried on Vitis Terminal, PuTTy and TeraTerm). I have installed the Cypress (now distributed by Infinion) USB to UART drivers and the board comes up on the device manager as a serial device.  I have also tried plugging the J14 port into my Macbook and using screen, but it still has the same issue. All the boot jumpers (JP7-JP11) are grounded.

I am using Windows 10 and Vivado and Vitis 2022.2. Are there any other reasons as to why it would be printing junk?

Thanks.

[JColvin]

Hi @rward,

I apologize for the delay; I haven't gotten the chance to be in the local office to try this out directly on a Zedboard.

What revision of the Zedboard do you have? When you add in the Zynq processor, which board file (Zynq preset) do you use?

Thanks,
JColvin

[rward]

On 12/21/2022 at 11:46 AM, JColvin said:

Hi @rward,

I apologize for the delay; I haven't gotten the chance to be in the local office to try this out directly on a Zedboard.

What revision of the Zedboard do you have? When you add in the Zynq processor, which board file (Zynq preset) do you use?

Thanks,
JColvin

Hi JColvin, no worries at all - I have solved my issue - the board files I downloaded from the Digilent website (https://digilent.com/reference/programmable-logic/guides/installing-vivado-and-vitis) seemed to have configured the clocks incorrectly, as the main input clock in Vivado was set to 50MHz rather than the 33.33MHz it is supposed to be set at. I downloaded different board files from Avnet, the problem was fixed, and the clock values had changed to there seemingly correct values.

[artvvb]

This issue has since been fixed in the Digilent board files in version 1.1 of the Zedboard board files, which can be found in the vivado-boards repo on Github: https://github.com/Digilent/vivado-boards

Thanks,

Arthur