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AR# 64498

2014.x/2015.1 - ZHOLD_DELAY insertion is not disabled when IOBDELAY is set to "none"


In order to avoid ZHOLD_DELAY automatic insertion when the input register is packed into IOB, I applied the following IOBDELAY property to the input buffer.

set_property IOBDELAY none [get_cells ibuf_inst_name]

However, after implementation is done, I still see ZHOLD_DELAY in the input path.

Why is it not working as expected?


The property value is case sensitive and needs to be defined in upper case.

The following command will correct the constraint:

set_property IOBDELAY NONE [get_cells ibuf_inst_name]

AR# 64498
Date 05/28/2015
Status Active
Type General Article
  • Vivado Design Suite
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