Controlling the LEDs with a 74HC595 chip

I finally got the 74HC595 chips and decided to do a dry run on a breadboard. I used the schematic I made earlier with Fritzing and just rebuilt it, with a couple of LEDs on every chip. I used the code from this blog as a base and it worked on the first try. Now I have to adapt this code for my purposes.

Don’t panic, the test setup looks worse than it is ­čÖé

Working on the front plate

I started my second try on the front plate. Printing directly on the card board didn’t work out that well, so this time I printed it mirror inverted on a DIN A3 paper (the same size as the card board) and used spray glue to attach it to the card board. Then I used a crafting knife to cut out the characters, as before. This turns out to work pretty well, I guess the paper gives the card board even a little more stability.

Nevertheless this is a hell of work, the next time I’m doing something like this I have to come up with a better Idea for the front plate.

Thoughts on connecting the LEDs

This is a summary of some thoughts I had on connecting the LEDs to the Arduino. When I read about charlieplexing I was amazed how many LEDs I could control with so few pins on the Arduino. Then I realized the downside of this technique: Essentially I can only light a single LED at a given time. Sure, there are a couple that can be lit┬ásimultaneously when they don’t share any pins, but setting those up would be a nightmare. So I started to group the words. Which words have to be lit when? Continue reading Thoughts on connecting the LEDs