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xilinxer
Observer
Observer
302 Views
Registered: ‎03-15-2021

ZCU111 DAC TVALID unconnected

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Hello,

We are working with a ZCU111 and instantiated multiple DACs in the FPGA fabric (Vivado 2019.2, RF Data Converter 2.2).
Everything works so far and we are able to generate signals, however, there is an issue with the TVALID signal to the DAC's.
According to the specification and PG269 Table 113, we assumed that de-asserting TVALID would result in no output (except noise) on the DAC, however, the data provided on the TDATA signal is still replayed.

Digging deeper, it turns out that the TVALID signal is not connected, and it seems like the connection is missing in the RFDC module, therefore being optimized away. This can be seen in the netlist already after synthesis.

xilinxer_0-1625147542411.png

In Vivado, the following log message is displayed:

"[Synth 8-3331] design ps_system_rfdc_0_block has unconnected port s00_axis_tvalid"

Is it expected behaviour that this signal is unconnected?

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1 Solution

Accepted Solutions
klumsde
Moderator
Moderator
238 Views
Registered: ‎04-18-2011

TVALID is not used in the IP 

klumsde_0-1625222880358.png

 

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1 Reply
klumsde
Moderator
Moderator
239 Views
Registered: ‎04-18-2011

TVALID is not used in the IP 

klumsde_0-1625222880358.png

 

-------------------------------------------------------------------------
Don’t forget to reply, kudo, and accept as solution.
-------------------------------------------------------------------------

View solution in original post