Various Stuff......

 Projects in hardware/software, and things in between.

                                
Please note that this is not, and is never intended to be, a professional or commercial page. ........
If you are looking for something proffessional, try my linked in profile
View my profile on LinkedIn

Currently  this is where I keep some odds and ends that I have been/am working on.
Anything here is freely available for anyone to read or use as they please.
However, it is all given 'as is' -- there is little formal documentation. Any questions, please feel free to e-mail me. Address is provided below,
but you will have to get through the mild obfuscation, hopefully sufficient to make it illegible to crawlers, but not too hard for humans  to work out....

To Email me:

Take the domain name from this page.  Thats the obvious bit. Then,send to ‘void’  at that domain
In other words ,  my email address is  
v**d@peterbrewster.co.uk    That’s, right, correct the asterisks!  It does say void  . Hope that makes sense!

Before we get to the techy stuff, recruiters/agencies - feel free to take a copy of my CV if of interest. 

 Here's my CV.My CV (draft) It's a 'web-safe' version, with contact details and actual names of companies not shown.
While I am not actively seeking new opportunities, there's no harm in asking!
  

Anyway, here's the archives:

 SincFilter package download  

This is a zip archive of my windowed sinc filter program. It creates a suite of windowed sinc filters kernels, 
based on the user parameters, and creates low,band, and high pass filters. It then applies these to an input wave file.
The wave file and 
user parameters are defined in plain text (ASCII) files. All the outputs, including the kernels are 
presented in text files
Instructions are included. Written in C++, built as a console application .exe is included,
but so is all source and build script. Should be fairly easy to Re-build for linux etc.

. 

 Spectrogram Source code download     

This is an FPGA project. Written in VHDL, it creates a real time spectrogram and displays it directly on a VGA
monitor.This release has a set of emulated data built in, and runs as a demo. Some work may be needed to inteface to
your data source e.g. an ADC, or a serial interface. This has been built and tested under the Altera Quartus package,

and run on a   ‘DE1’ dev kit. This distribution does not contain all the simulation files, as they come out at 95Mb.
This would be quite
a stretch for a complete newcomer to build, would suggest you get familiar with the project

structure under Quartus,   (and know how to insert megafunctions)

  

    MSc Dissertation                         

Dissertation for my MSc. The project was to design and implement an FPGA based, real time, spectrogram displayed on a VGA monitor.
The  Code above is more or less one of  the implementations of this, so if you are playing with that  code, you may find it worth wading 
through this paper. It’s a bit long, so would suggest skim reading it to see if any of it is useful.

  MiscTools download  

These are a couple of spreadsheets  (open office/libre office .ods format). They were created during the development of the spectrogram project as tools . A bit specific, but could be useful in other places.

1.FourSines.ods creates a signal from the summing of  four sines,  and has a viewer for plotting the magnitudes of  real and imaginary data

2.HannTableArrayi maker.ods is a tool for creating look up tables that can be pasted into a VHDL elements. It also can create VHDL LUTs
   of  
sine functions. You should be able to work out how to use it yourself, but don’t hesitate to mail for help if you need it.

Have started to move the cryptography stuff to a proper set of pages : use the link below

 

Cryptography Page

----- for  contituity only - below is original stub on cryptography, follow link above  for actual page

This really justifies a page to itself, but for now it's all just dumped here, The intention is to document it a bit better.
What is given here is a pair of tools. Both are found in the archive below
. All sources are included

   Encryption tools

The tools are:

Encryption tool   download   -complete, coming soon..This is a fully working encryption tool, all source provided. It processes text (ASCII) 
files with a key (one time pad) The same program encrypts and decrypts, depending on a parameter passed to it. A ‘salt’ is applied during the
Encryption process, providing a further obstacle should some attacker somehow obtain the key.

Key Generator                           

This is a tool to create one-time pads for either the tool given above, or any other application that may require Substantial chunks of random characters. 
The keys generated are pretty noisy, having same 64 or so symbols.
The key generation has a few features to mask attackable statistical traits. 
These features include the addition of a salt, and some intermediate processing. If you want to understand more, read the source code! Another useful 
feature is that the Generator outputs a seed value, which can be used, in conjunction with the other parameters and the salt string, to regenerate a key
.

useful links,,,,,

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