Serial Loaders for AVR Microcontrollers

These devices allow you to load a program into an AVR that has a bootloader program burned into it, like an Arduino or Arduino clone. Bootloaders are faster than ArduinoISP knock-offs, but slower than the serial and parallel port programmers.

Discrete TTL Converter

This loader uses transistors and a charge pump to convert RS232 to TTL and back. It is not difficult to make, but may be more difficult than just using an IC and a few capacitors.

MAX232 TTL Converter

The MAX232 and it's kind are designed to solve this problem. They come in all flavors, are very simple to wire up, and are reliable.

USB to TTL Converter Board

These are USB to TTL converter breakout boards that are intended to be integrated into your project and dedicated to that use. They are not cheap, but are cheaper than the cables, generally, and make for a nicely finished product.

USB to TTL Converter Cable

These are USB to TTL converter cables that are intended to be used for all of your projects, and not dedicated to a single project. They are a little more expensive initially, but you only need one, where you might need one per project if you used breakout boards.

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Serial Loaders for AVR Microcontrollers