Or how to practice Safe Hex

Ah, the world of computers. Thanks to the wonderful world of bits and bytes, we can experiment with any application, file, driver, or even the core operating system. Rip them apart, change things, put them together, and if it doesn’t work, just try again. At worst, you’ll have to wipe your hard drive and start over. If you somehow manage to destroy a computer purely through bad software, that’s considered a design problem and a true feat to pull off. Just think about it: what other profession or hobby lets you experiment as much as you want and make as many mistakes as you want without having to spend a cent if you do something wrong?

Unfortunately, things have changed. Ever since the advent of embedded devices with upgradable firmware, people have been trying to modify and hack them. These devices are usually a lot less resilient than their bigger, older siblings. Many of the new shiny gadgets that we use every day are internally fragile and a slight software mishap can render them non-functional, a “brick”.

This is a guide for developers and hackers who work on system firmware for embedded devices.
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