Arduino Uno ISP

Arduinos are a great introduction to microcontrollers for starting electronics hobbyists. They are plug-and-play development environments that can introduce a plethora of topics about electronics, awesome right! The main model produced by Arduino, called the Arduino Uno, uses the Atmel 328P Microcontroller as the main brain on-board. Its stock package type is a large 28-pin DIP package. Very large and gives an excess of I/O pins that won’t be utilized in many projects. Atmel produces other smaller sized DIP package microcontrollers, the 14-pin Attiny84 and the 8-pin Attiny85 are two of the most popular.

The problem is that when you buy these microcontrollers from your distributer they are not automatically ready to be given instruction sets. A bootloader must be burned to these microcontroller chips before they are ready to be programmed. Also, if you want to write programs to these microcontrollers you would have to remove the stock 28-pin microcontroller every time you put a new chip in. This will eventually lead you to damaging an IC chip.

A solution is to use an ISP (In-System Programmer) to burn the bootloader and put your program on the chip. This can be done externally on a breadboard, but that’s a hassle. You have to get the breadboard, jumper wires, and be sure that you are hooking up to your main Arduino Uno unit every time (Here’s the article on Arduino’s website describing this process in more depth: ArduinoISP).

Rather than doing that I made an Arduino Shield, which is just a separate printed circuit board that sits on top of the Arduino Uno, that can program 28-pin Atmel chips, 14-pin Atmel chips, and 8-pin Atmel chips. The shield was designed in Eagle CAD and features three indicator LEDs that display when the chip is being programmed, has an error, and Heartbeat (To show that the chip in responding normally).

The shield was marked with “Swallowtail Electronics” on top. This is a small business I have started and am working on. More to come on that.

Article last edited: August 2021