DIY “Solid State Drive” Puts Four Bytes In Your Pocket

In a relatively short amount of time, the average capacity of USB flash drives has skyrocketed. It wasn’t so long ago that two and four gigabyte drives were considered to be on the high end, but today you can grab a 512 GB drive for less than $50 USD. In fact they’ve gotten so large that it can feel wasteful using them for some tasks, and we occasionally find ourselves wishing we could find some modern USB drives that didn’t rival the storage capacity of our whole computer.

That said, this USB-C tetrabyte drive created by [Glen Akins] might be slightly too small for our tastes. No, that’s not a typo. As in the Greek tetra, this drive can hold a massive four bytes at a time. Even better, you don’t need a computer to write to it: the 32 DIP switches let you key in the content on the fly, bit-by-bit.

Reading out the first byte from the DIP switches.

As explained in a Twitter thread, [Glen] was inspired to create this gadget after another user posted a picture of a 32 position DIP switch with a caption that said it was a “One Tetrabyte SSD” back in December. He apparently couldn’t track down the same switch, but the four red Grayhill 76 Series switches arguably make it a bit clearer when entering in your bytes.

Each of the individual DIP switches are connected to one of the GPIO pins of the 8-bit EFM8UB2 microcontroller, and the code simply reads the state of each pin in order and saves the binary results in a variable to put together the “file” it presents to the OS when plugged in.

We’ve seen our fair share of unusual USB flash drives in the past, but this one is truly in a league of its own. Can’t say we can think of any four bytes of data important enough to hold on a dedicated piece of hardware, but we certainly appreciate the effort to store it in the most robust way possible.

Thanks to [J. Peterson] for the tip.