What’s the difference between using shiftOut (which is software) and SPI (aka, hardware) on Arduino, and how does it differ between an AtMega and an attiny? I built a simple test circuit and tested a few different configurations.
I’ve been getting interested in playing with the attiny, in particular the attiny85 (8 pins!) and the slightly more practical attin84 (14 pins). So I built a very simple programmer that can program either of these and be easy to use while programming.
It may seem silly to talk about things that didn’t work. But those are the things that you learn from, more than the things that do work. So here are a few things I tried recently in an attempt to log temperatures throughout my house, and which failed to work as expected.
In this video, James “The Bald Engineer” Lewis goes into a lot of depth on the different processes used to create capacitors, the various pitfalls with aluminum and tantalum caps, etc. Lewis works for KEMET, one of the largest makers of capacitors, and clearly knows what he’s talking about.
Hans Camenzind’s Much Ado About Almost Nothing tells the story of the electron. Or rather, its discovery and how our understanding of electricity changed over time. It’s a big tour of some truly fascinating history.
Maybe music is overstating this a bit, but it’s creating sound (and makes for a second alliteration in the title). Measuring a constant voltage is one thing, but can the discrete DAC put out a waveform? After all, that’s the main idea behind using a digital-to-analog converter (DAC) rather than pulse-width-modulation (PWM).
Arduinos have analog outputs, but they generate a pulse-width modulation (PWM) signal rather than a voltage. There are a number of circuits to create a voltage from a bit representation. One of the simplest and most elegant is the R/2R network, which only needs two resistors per bit.