Provides fault-free circuit simulation, deductive fault simulation, and PODEM test pattern generation for the single-stuck fault model in one extensible and self-contained Python library.
External Dependencies: None! Only Python 3.13 required.
Implements the 5-valued "D-Calculus" logic simulation (0,1,D,D̅,X).
- 0 : Logic low
- 1 : Logic high
- X : net with unknown/no logic level
- D : faulty net at 0 instead of 1
- D̅ : faulty net at 1 instead of 0
- Only 2-input AND/OR/NAND/NOR and 1-input inverters & buffers are supported
- No XOR gates
- The
Circuitclass can be extended to support parsing netlists in other, more standard formats.
The groundwork is here, I would like to revisit and add these features one day™
from atpg_toolkit import TestGenerator, FaultSimulation, Fault
from atpg_toolkit.util import str_to_fault
netlist = [ 'NAND A B E',
'AND C E F',
'OR D E out2',
'NOR A E out1',
'INPUT A B C D -1',
'OUTPUT out1 out2 -1' ]
# netlist can be a file or a list of gates
# net names can be letters/numbers/words
podem = TestGenerator(netlist)
fault = Fault('out1', stuck_at=1)
# fault = Fault('E', '1')
# fault = str_to_fault('E-sa-1')
# fault = str_to_fault('E 1')
found_test = podem.generate_test(fault)
print(found_test)
sim = FaultSimulation(netlist)
# produces set of faults detected by a test
faults = sim.detect_faults(found_test)
print(*faults)See tests and the cli implementation for more examples
The primary usage of ATPG Toolkit is as a library for other python scripts.
However, a basic command-line utility is available for demonstration purposes, or to combine with output from other processes (see scripts/ for examples).
When installed as a package, you can execute python -m atpg_toolkit to see the CLI usage. A entry point is also installed, and available as atpg-toolkit.
For more convenience as a tool, the ./atpg-toolkit script can act as an executable entry-point on systems with script Shebang support. No installation of the package is necessary (but recommended).
$ python -m atpg_toolkit faults --help
usage: __main__.py [-h] [-v] {faults,f,generate,g,simulate,s} ...
Generate test patterns or simulate faults on digital logic circuits.
options:
-h, --help show this help message and exit
-v, --version show program's version number and exit
Actions:
{faults,f,generate,g,simulate,s}
faults (f) Find detected faults with a given net-list and test vector(s)
generate (g) Find a test vector that detects a given fault
simulate (s) Perform fault-free simulation with a given net-list and test
vector(s)
Copyright 2024, jack-mil. Source: https://github.com/jack-mil/atpg-toolkit
You can install the package with a tool like uv or pipx to make the tool available at the user level.
$ atpg_toolkit generate circuits/s349f_2.net 85-sa-1 10-sa-0 179-sa-1
Circuit: circuits/s349f_2.net
Fault | Test
10-sa-0 | XXXXXXXXX1XXXXXXXXXXXXXX
85-sa-1 | 01X01XXXXX1XXXX0XXXXXXXX
179-sa-1 | UNDETECTABLE
$ python -m atpg_toolkit faults circuits/s27.net 1110101
Circuit: circuits/s27.net
Input Vector: 1 1 1 0 1 0 1
------ Detected Faults (8) ------
1 stuck at 0
3 stuck at 0
5 stuck at 0
7 stuck at 0
9 stuck at 1
11 stuck at 1
12 stuck at 0
13 stuck at 0
$ python -m atpg_toolkit simulate circuits/s27.net -f scripts/data/s27-tests.txt
Circuit: circuits/s27.net
Inputs | Outputs
1110101 | 1001
0001010 | 0100
1010101 | 1001
0110111 | 0001
1010001 | 1001
This project implements textbook concepts for a course on digital systems test generation. It is not recommended for any critical or serious test generation needs. The code serves as reference and a learning aid only. There is no guarantee of efficient operation or correct output.
Miron Abramovici, M. A. Breuer, and A. D. Friedman, Digital Systems Testing and Testable Design. Wiley-IEEE Press, 1994.
P. Goel and B. C. Rosales, "PODEM-X: An Automatic Test Generation System for VLSI Logic Structures," Proc. 18th Design Automation conf., pp. 260-268, June, 1981.