Thursday, 24 December 2009

Name that device

*Blows off the dust*

Wow! It has been a while. Sorry for not writing anything of late!

I have decided to take a leaf out of the great Bunnie's book and write some blog entries about hardware teardowns of interest. I regret that I cannot offer a prize just yet but I wonder if anyone will be able to name the following hardware? It's a piece of 1980s technology that I found in my old bedroom at my parent's house. A *fairly* easy one to guess the function of, yet the exact model may challenge some...

From 74HC04

(Click to enlarge)

Monday, 16 February 2009

Motivation for myself. Bit bashing a serial interface to a MC14499

I've had this bit of retro junk lying around for a while.

That broken PCB was once part of the display of an Amstrad SDR4000 (IIRC) analogue satellite receiver (Don't ask how I remember model numbers - I don't know either) and sports a Motorola MC14499 7–segment LED decoder/driver with a serial interface.

As such, I figured it would be a great bit of kit to interface with a simple PIC, using one of the built in timers for clock generation. The eventual aim being to make a logging thermometer or somesuch, using a DS1820 or similar digital temperature sensor.


Sunday, 18 January 2009

Pseudo-Random Number Generator with pseudo-random delays.

One of my more recent assembly hack-togethers. Here I created an 8 bit pseudo-random number generator, with pseudo-random delays implementing a software linear feedback shift register. (The code has also been ported over to a 16F887 [video]).

Binary counter using a PIC

My first ever PIC project. An 8 bit binary counter (only the least significant nibble is shown), running on a PIC16F690. Since we're all used to high-level languages these days, this might look a bit trivial, but it takes quite a few lines of assembly language to do this.

HD44780 compatible LCD running from parallel port

OK, it's hardly breaking new ground but last April I had a new 2x16 LCD lying around that I needed to test. Here's a quick video of the test (originally intended for my LJ), using LCD smartie and some stripboard.

Hello world

I created this blog as a means to organise my thoughts, ideas and creations with regards to something that takes up a fair proportion of my idle thought - most simply put, Technology. Expect bad coding, dodgy tear-downs, prototyping and a bit of ranting for good measure :-)

As an IT professional and Electronics Engineering graduate, I've had an interest in the products of Engineering for as long as I can recall.

(BTW - if you were wondering about the title of this blog, be glad you have a life ;-). It's an goth-nerd in-joke about logic gate based jewelery. A 74HC04, is of course, a hex inverter.)