RIP Dennis Ritchie

The world has lost one of it's
greatest programmers.

I missed it in the news and just now read about it.  Dennis Ritchie, the father of the C programming language, died on October 12, 2011 at the age of 70.  The work that Dennis has done to bring modern computing to us cannot be overstated.

From Wikipedia:

Ritchie was best known as the creator of the C programming language, a key developer of the UNIX operating system, and co-author of The C Programming Language, commonly referred to as K&R(in reference to the authors Kernighan and Ritchie). Ritchie worked together with Ken Thompson, the scientist credited with writing the original Unix; one of Ritchie's most important contributions to Unix was its porting to different machines and platforms.

The C language is widely used today in application, operating system, and embedded system development, and its influence is seen in most modern programming languages. UNIX has also been influential, establishing concepts and principles that are now precepts of computing.

Ritchie was elected to the National Academy of Engineering in 1988 for "development of the "C" programming language and for co-development of the UNIX operating system."

We will miss you Dennis.

LED Analog Clock

The LEDs are blue

 I got inspired the other month about a Nuts and Volts article on an LED analog clock.  This is my take on the project.

I started with a thin piece of board and cut a square out of it with the table saw.  Next a sat at the kitchen table for several hour while I figured out how I was going to lay out the LEDs.  I finally settled on 24 "Hands" and 4 "Tiers" plus the center dot.  Originally I planed on having more tiers, but I had cut the board to small and this was the most I could fit on and keep the tiers evenly placed.

My hand hurt from striping all that wire

The LEDs are wired into a 24x4 matrix controlled by 3 74HC595 shift registers and 5 digital I/O pins (4 for the matrix 1 for the center dot) connected to an attiny2313.  I have a DS1307 real time clock (RTC) connected over the I2C bus to provide the time keeping for the whole piece.

I still have yet to encase this mess

Savy viewers might note the batteries are only hooked up to the RTC, and they would be correct.  The batteries are only there to make sure the RTC keeps it's time and do not power the entire circuit.  I have yet to decide on how I want to power the clock, I could either choose a large battery pack and hope that it powers it for a long time (not likely) or I could tear up a wall wart and regulate the power to 5v and have it plug into a wall.

In a future version I think I'll move to
strip board instead of pad per hole

Apart from said power issues, the clock does work.  I do have a few additions I would like to make to it.  Mainly it needs a couple of buttons on it so that the time can be adjusted.  Currently the time can only be set by programming the AVR chip on board, and I need some way to adjust for daylight savings time.  The second big improvement it needs is some kind of frame to hold all of it's "guts" inside, instead of this mess of wires hanging out.  Lastly I was thinking to program in some "demo" modes because, well, I have a 97 led display and I want to do neat things.

I'll see about drawing up a schematic and posting code in the next few days.

Welcome to OMG-LED

Greetings guests, and welcome to OMG-LED.  There isn't much here, and to be honest I don't know if there ever will be a lot.  The purpose of this site is kinda of a "stuff drawer" of projects of mine, things I find interesting, rants, raves, and just about anything else.