Serial communication between computers and/or microcontrollers allows messages to be sent using a single wire. The message takes the form of a series of voltage pulses that encode a sequence of zeros and ones. There are two main protocols for serial communication, TTL and RS232. The major difference between the two is the voltages that

I recently looked for a really good schematic for a breadboard Arduino and couldn’t find one so I made one and share it below. This schematic is for an extremely bare-bones circuit and includes only the needed components to operate a ATmega328 running the Arduino Uno bootloader. I leave it to you to design your

For an introduction to binary and hexadecimal notation, read this post. In the Arduino IDE, representing numbers in binary or hexadecimal notation often comes in handy. For example, since the ATmega328’s registers are eight bits, I often set the bits of a register by assigning the register an eight-bit binary number. To assign a variable

A relatively easy way to same a few milliamp hours of battery energy is to disable features of the ATmega328 your Arduino project isn’t using. Below are some examples of code you can use in your setup function to do this. void setup(void) { // The following saves some extra power by disabling some //

The voltage regulator built onto the Arduino Uno is a linear-type regulator and is horribly inefficient. If you are running the ATmega238 at 5V using a 9 V battery, approximately half of the battery’s energy will be dissipated as heat by the regulator. This post demonstrates a DC/DC switching-type voltage regulator circuit that can be