In this tutorial and accompanying youtube video (left), I discuss how Arduino inputs and outputs work. Arduino 8 bit boards are mainly based on Atmel AVR chips, in fact the Mega is named after the chip number AVR-Mega-2560. Outputs on the AVR chips are much more versatile than they first look, and the video covers this in detail. If you are...
When writing Arduino code that needs quite a few IO pins, you may need to expand the IO using a shift register or i2c expansion device such as the PCF8574. Up until now that meant significantly changing your code to use the new device. If you were using the IOAbstraction library , then you'd just set up a different type of...
Over the years, I've done my fair share of wood and metal work, including quite a lot of router work. For some tasks, I think a good router table is really needed, so I've took a bit of time out from my other projects to build a good router table. After much looking around, I came up with a hybrid, based...
At the moment I am prototyping a high quality pre-amplifier based around the PGA2310 volume control and an op-amp buffer input with RF filtering. Each channel will be selectable by relay, along with gain adjustment for each channel in terms of increase in dB. Each channel will be assigned a name that can be changed easily in software and stored along...
Over the past month or two, I've finally fixed up some snags that I had when building the honey badger amplifier. When I first built it, I had a difficult time trying to track down dry joint on one of the start boards - it also had a bad IDC connector delivering power to it. In addition the PSU boards had...
Over a couple of years, I slowly built out an amplifier based on the DIYaudio honeybadger design . It was an on/off process where I got one part of it working at a time. Starting by building the channels one at a time on a bench PSU. This project consists of a single large transformer and dual mono PSU boards with...
In this article I describe how to wire a 20x4 character display to an Arduino. I'm assuming you are using a regular 5V 8bit Arduino, if this is not the case this article will not work for you as you'll need voltage level converters. Most character based LCD displays use the same wiring, but I can't guarantee that all will be the...
Here we discuss a game library that provides an easy way to write games with 20x4 parallel display and a few micro-switches. There is quite a lot of stuff going on in this library, so I'd like to start slow and build up. First, let's start by taking a look at the parts needed to use this library: 20x4 display (other...
In this article we'll discuss building a low power Arduino menu using tcMenu library. We will use a TFT screen and a rotary encoder connected to a PCF8574 device. The device will be SAMD MKR board. I've picked this choice purposely, because it's non-trivial, and requires a lot of digging to make sure power usage is a low as possible. Running...
When we press a button that's connected to an Arduino input, it is likely that the button will momentarily "flicker" between the on and off state. This gives false readings for a short period of time after the button is pressed. Problems caused by this can range from the mild annoyance of a slight flicker, to doing something more than once...