Beginner Concepts: Binary-coded decimal
posted Jan 8th 2010 1:00pm by Mike Szczysfiled under: led hacks, misc hacks
A rudimentary understanding of digital logic and simple integrated circuits is critical if you’re ever going to pull off some really gnarly hacks. [Daniel] put together an explanation about the use of 4511 BCD 7-segment drivers. These chips take binary data in and output decimal data to a 7-segment LED display. In short, they can read 0b1001 from input pins and light the numeral ’9′ on the display. The best part is that you can build this example circuit in the Atanua logic simulator without ordering parts. We love zero-cost learning!
I was so proud when I wired up my first BCD chip last month, I even made a video of it: http://bit.ly/8DjNaL
Mine was a MC14543B and I had all sorts of weird problems where lights would turn on / off depending on how close my hand was to the wires until I added pull-down resistors.