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
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:
- When you manually connect any of the
<name>_Tports, either by making them external or by connecting it to another IP in the design.
- When the interface has the
BUFFER_TYPEparameter set to
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.