diff --git a/README.md b/README.md
index 705df1623e12c0495747573afc9430528c30225f..9ee08309a7f19647cc4fcd6be1f6e20fa54eb8b7 100644
--- a/README.md
+++ b/README.md
@@ -20,6 +20,8 @@ Implementation of a Basic Distributed Arithmetic Architechture for MAC
 
     The generate multiplication coefficients can be stored as an unpacked array of packed values and should be connected directly to the           `multiplication_coefficients` input port.
 
+- One should provide to the `in` port, an unpacked array of size `N`, with each value being a packed array of size `BW`.
+
 **Example**
 
 An Example ModelSim output for the testbench provided, which displays the inner product of