It has become a bit of a managing joke in the Hackaday local community to propose that a project could or really should have been carried out with a 555 timer. [Tim] has rather taken this to heart with his most recent Digital Dice undertaking, which makes use of 3 of the venerable units.
If a few seems like a ton of 555s to make an electronic die, then it may be truly worth taking into consideration that the past time we shared his project he was working with 22 of them! Because then, [Tim] has been busy optimising his layout, whilst trying to keep within just the constraints of an outdated-faculty by-gap soldering package.
It’s possible the most shocking detail about this project is the purpose to which the NE555 equipment are pressed. Instead than using them for their famous oscillation properties, they are in true fact just staying made use of as Schmitt Triggers to clean up up the a few-period ring oscillator that is built from discrete transistors and passives.
The ring oscillator cleverly makes a few stage-shifted sq. waves such that a binary blend of the three phases features six one of a kind states. Six becoming the excellent number for a dice throw, all that then continues to be is to figure out which LEDs require to be switched on in which state and wire them up accordingly.
To “roll” the dice, a force-button powers up the oscillator, and stops it all over again when it is launched, displaying the random finish-condition on the LEDs.
It can be entertaining to see what can be accomplished applying outdated know-how, and instructional to try out to optimise a design and style down to the fewest parts probable.
[Tim]’s before venture is listed here if you want to see how the structure has advanced. The documentation on equally of these iterations is great and properly well worth a read through.