Instantiating I/O Buffers - 2021.2 English

Vivado Design Suite User Guide: Designing IP Subsystems Using IP Integrator

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2021.2 English

When generating the wrapper, IP integrator looks for I/O interfaces that are made external in the BD. If the tool finds external I/O, it reviews the port maps of that interface. If the tool finds three ports matching the pattern <name>_I, <name>_O, and <name>_T, then it instantiates an I/O buffer and connects the signals appropriately. If any of the three ports are not found, then an I/O buffer is not inserted.

Other conditions in which I/O buffers are not inserted include the following:

  • If any of the <name>_I, <name>_O, and <name>_T ports are manually connected by the user, either by making them external or by connecting it to another IP in the design.
  • If the interface has the BUFFER_TYPE parameter set to NONE.

To manually instantiate I/O buffers in the BD, you can use the Utility Buffer IP that is available in the Vivado IP catalog. This IP can be configured as different kinds of I/O buffers as shown below. See the LogiCORE IP Utility Buffer Product Brief (PB043) for more information.

Figure 1. Utility Buffer IP Configuration Dialog Box