Small bytes: Program counter

Small bytes: Program counter

One of the current projects I’m tinkering with is an 8-bit computer. It’s something I’ve wanted to build for several years, and now that I’ve finished so many other projects, I finally have the bandwidth to take this on. I’m aware that Ben Eater has done this, and I’m not intending to compete with his …

Generating digital clock signals

Generating digital clock signals

Any synchronous sequential digital logic circuit requires a clock source (a square wave oscillating between logic LOW and HIGH values) for the circuit to function. Typically, a clock frequency is determined by the circuit designer (taking into account speed requirements as well as any limitations from the circuit components themselves). Once that frequency is known, …

Two takes on multiplication

Two takes on multiplication

Apparently, people actually read this blog (who knew!), so why not write about a topic I find interesting: multiplication. Multiplying two values together (as opposed to multiplying one value with a constant) is actually a difficult computational task. This was difficult to do in mechanical analog computers (shout out to any potential future mechanical engineers …

Cleaning Up a 555 Timer Signal

Cleaning Up a 555 Timer Signal

Sometimes a 555 timer does not output a great square wave from 0-5 V. In this case, when using it as a clock source for a flip-flop, a bad 555 timer output can lead to missed clock pulses and seemingly strange behavior on the output. To correct this, use one or two Schmitt inverters (7414) …

Creating Hobby Project PCBs

Creating Hobby Project PCBs

The purpose of this post is to make the design process of creating printed circuit boards (PCBs) a little less scary. Please note that, as with most of the hobby stuff on my website, I am self taught. This means that I use auto-routing, don’t worry about ground planes, and the most difficult thing I …