UPC EETAC Bachelor's Degree in Telecommunications Systems and in Network Engineering EEL


Adder_1bit plan C2: structural hierarchical multiple-file VHDL


Example on how to use MoD for implementing logic functions

1. Specifications

Design a 1-bit adder using a hierarchy of components based on method of decoders discused in L3.3.


Fig. 1. Symbol and truth table of a 1-bit adder circuit. It is also called full adder.

This in Fig. 2 is a simple sketch that represents the truth table in time. The idea of applying input vectors that can be any binary combination.


Fig. 2. Timing diagram where all the inputs are applied sequentially and hence, the output is predicted accordingly to the truth table.


2. Planning

The VHDL file will be named Adder_1bit.vhd, the same name given to the entity. The project name is Adder_1bit_prj.

Plan C2) Building blocks (hierarchical structure , multiple-file project):

- Plan  using MoD to implement logic functions.

This project will be located at:   



3. Developing the project using EDA tools

The top entity Adder_1bit.vhd, and the Dec_3_8 internal component using  a plan B description (that you see, it is a project in itself).

Target chip: MAX10 10M50DAF484C7

RTL and technology schematics.


4. Testing and validating the design

 An example test bench Adder_1bit_tb.vhd. Run the VHDL simulation EDA tool to obtain and discuss the timing diagram.  Remember that from the testing point of view, even if you have designed the Adder_1bit using several plans, you can use all the time the same testbench.


Fig. 4. Example testbench showing results


5. Report

Project report starting with the template sheets of paper, scanned figures, file listings, docx , pptx, or any other resources.

 Follow this rubric for writing reports.

6. Prototyping

Use training boards and perform laboratory measurements to verify how the circuit works.