Logic Synthesis Engine

About

This program takes a blif file¹, and based on user commands can:

1. Output the canonical function (POS/SOP)
2. Output the inverse canonical function (POS/SOP)
3. Minimize the function and output the resulting function and how many terms saved (POS/SOP)
4. Print the # of prime implicants, essential prime implicants, onset maxterms and onset minterms
5. Output a graphical Kmap and tabular method representation

A few limitations of this program is that it doesn't recognize blif syntax outside of: names, model, input, outputs. It also can't work with functions that have more than four inputs.

Files

ec551p1.py : This is the program which is responsible for taking user input and runs the canonical outputs

program1.py : This program generates graphics and minimizes expressions using the tabular method.

There are also two demo blif files. The bool.blif was arbitarily generated and checked by hand. The priorityEncoder.blif acts as an example of a circuit. The blif file references this. ²

How to read the code

The code is seperated into two modules simply due to time/collaboration reasons

ec551p1.py

There are a few comments throughout the code explaining what is happening. First, the blif file is parsed so that the '.model', '.inputs', '.outputs', and '.names' are stored. The most important component here is the names. The program works with multiple '.name' sections. For each name section, a truth table is generated and stored within a dictionary entry, with the list of variables as the key. There are two dictionaries used, the first stores the truth table as a list of numerical strings 'names', and the second stores it as a 2D array 'names_tt'. The program then uses each entry (aka name section) to generate strings for the canonical representations.

program.py

This file contains all the functions necessary to complete deliverables 5-12. It also contains many helper functions utlized by the main functions. In order to find essential prime implicants, it follows the tabular method. Note that to find the minimized POS and SOP, one function is utilized and the formatting is handled later.

References

Footnotes

1. https://course.ece.cmu.edu/~ee760/760docs/blif.pdf ↩

2. https://www.tutorialspoint.com/digital_circuits/digital_circuits_encoders.htm ↩