Hier Blocks and Parameters

This tutorial describes how to create a hierarchical block, or Hier block, in GRC. The previous tutorial, Creating Your First Block, demonstrates how to create your first GNU Radio block using the Embedded Python Block.

Creating a Flowgraph

A hier block is used to encapsulate and simplify multiple GNU Radio blocks into a single block. The example hier block will be a frequency shifter block which multiplies a Signal Source against an input signal.

The first step is creating the flowgraph: