www.deadhat.com.
Randomish things from the confused mind of David Johnston — simulators, random number generators, signal processing and other tools.
6502
Tools for the 8 bit CPU that refuses to die.
Random Numbers
Generating random data, testing it, and reading about it.
djenrandom
A C program to generate random data using several random models, with parameterized non-uniformities and flexible output formats.
quickrdrand
A C program to quickly generate lots of uniform random data using RdRand or RdSeed.
djent
A reimplementation of the Fourmilab/John Walker random number test program ent, with several improvements.
SP800-22 Tests
A Python program implementing all of the SP800-22 Rev1a tests for distinguishability from random.
Use RdRand and RdSeed in C
A C library for RdRand and RdSeed. It implements the necessary inline assembly for both Windows and Linux, along with support detection routines and buffer filling functions.
I wrote a book! Random Number Generators, Principles and Practices
Read all about random numbers and random number generators.
Software Tools
Online calculators that run right here in the browser.
Online Polynomial Divider
Frustrated with my inability to ever get synthetic polynomial division right first time, I wrote a little algorithm and web page to automate the process.
Online CRC Unroller
A utility to generate the lookahead equations for a parallel implementation of a serial CRC.
Online LFSR Unroller
A utility to generate the lookahead equations for a parallel implementation of a serial LFSR.
Radio & Signal Processing
Filters, antennas, modems and Morse code.
Remez
A digital filter program supporting FIR and IIR filters, which will generate C, SystemVerilog and VHDL implementations of the filters designed in the program.
Ham Channel
A program to provide an OFDM+LDPC data channel over amateur radio FM audio channels.
yagiyagi
A cross platform antenna design GUI: quick, interactive and easy to use, pre-populated with most common antenna types as parametric models.
necfull
A segmented electromagnetic antenna modeller. Lawrence Livermore National Laboratory charge large amounts of money for NEC-5, and EZNEC uses the LLNL NEC-5 library — free, but closed source and Windows only. Having had my neck full of closed source antenna design packages, I recreated NEC and named it necfull. Compared to yagiyagi it allows free creation of arbitrary shapes, realistic ground models and finite element antenna modelling.
Morsey
A program to assist with learning Morse code.
Cryptography
Wireless standards cryptography notes and test vectors.