Important news about HackSpace

We have some important news to share about HackSpace: Issue 81 was the last issue of HackSpace as a standalone magazine, and HackSpace has become part of The MagPi, the official Raspberry Pi magazine. Starting with issue 145, We’ll be adding pages to The MagPi to make room for the stories and tutorials you’ve come to expect from HackSpace.

How do you tell the time in binary?

By Andrew Gregory. Posted

I am David Watts (yes, I have heard the song), and I am a self-styled maker/tinkerer. I learnt how to wire a plug at school, but that is about as far as my electronics education extends.

I call this the ‘BCD Crap Clock’ – why? Well, it lowers expectations with the hope of exceeding them. BCD stands for Binary-Coded Decimal – you see, it isn’t a true binary clock.

This is a fairly crap ‘binary’ clock kit made with CMOS logic, a simple design without a microcontroller, and it has the unique feature of being both difficult to read and difficult to set the time! It is a curiosity rather than a real timepiece, but it is at least better than guessing the time. Consider it an exercise in learning about CMOS logic and making my first kit that would go on to sell out in a day on Tindie.

It uses quite a few ICs for something that could be achieved with one PIC or ATmega but hey, there are advantages. It runs down to about 2.7–3 V, consuming 0.5 mA with LEDs enabled or ~6 µA with the LEDs disabled, meaning it could keep time for decades on a few AA cells. Also, I get ‘no microcontroller’ bragging rights.

hsmag.cc/AmubiW

From HackSpace magazine store

Subscribe to our newsletter