microsd card

3 Articles

The SDWire board plugged into some SoM's breakout board's MicroSD socket

Automated MicroSD Card Swapping Helps In Embedded Shenanigans

August 8, 2022 by 20 Comments

[Saulius Lukse] has been working on some single board computer, seemingly, running Linux. Naturally, that boots from a microSD card – and as development goes on, that card has to be reimaged all the time. Sick of constantly plugging and unplugging the microSD card between the SBC and an SD card reader, [Saulius] started looking for a more automated solution – and it wasn’t long before he found out about the SDWire project, a hardware tool that lets you swap a card between a DUT (Device Under Test) and your personal computer with no moving parts involved.

SDWire is an offshoot from the Tizen project, evidently, designed to be of help in device development, be it single-board computers or smartphones. The idea is simple – you plug your MicroSD card into the SDWire board, plug the SDWire into a MicroSD slot of your embedded device, and then connect a USB cable from the SDWire to your development computer. This way, if you need to reflash the firmware on the SBC you’re tinkering with, you only need to issue a command to the SDWire board over the USB cable, and the MicroSD card appears as a storage drive on your computer. SDWire is a fully open source project, both in hardware and in software, and you can also buy preassembled boards online.

Such shortening of development time helps in things like automated testing, but it also speeds your development up quite a bit, saving you time between iterations, freeing you from all the tiny SD card fiddling, and letting you have more fun as you hack. There’s a clear need for a project like SDWire, as we’ve already seen a hacker assemble such a device using breakouts.

Console Macropad Uses SD Cards For Stylin’ And Profilin’

May 26, 2022 by 7 Comments

Macropads are great to have around for hotkey input, but things can get out of hand pretty quickly when you realize just how many shortcuts are in your life. To avoid ending up with another keyboard-sized keyboard, some hackers will use a handful of switches and a lot of layers to turn a few keys into many. And instead of worrying about legends, they use blank keys and leave the labels to be displayed on some kind of screen.

Among them is [QCJ3], who built this nifty little console-style macropad. Uninterested in managing microcontroller memory, [QCJ3] went the tangible route and loaded various profiles onto a micro SD card. Each text file on a given card holds a label, a color for the keyswitch LED, and of course, the keystrokes that make up the macro itself.

There are myriad ways to build a macro pad, from designing with bare chips (if you can get them) to programming a pre-built key matrix.  Grab the files if you like the console look and call it a day, or build a completely new enclosure that fits your hand exactly. Whatever you build, consider entering it in our brand spankin’ new Odd Inputs and Peculiar Peripherals Contest, which runs now through July 4th. If you need more inspiration, just peep the projects under macropad tag, or peruse the much heftier keyboard tag.

Via KBD

USB Flash Drive Reveals Strange SD Card Heart

July 17, 2020 by 41 Comments

Many a hacker has dug an old flash drive out of the bottom of a backpack, and peeled apart the damaged plastic case to look inside. More often then not, you’d expect to see some SMD chips on a PCB along with a few passives, an LED and a USB port. [Gough] found something else entirely, and documented it for the interested public.

Inside the Comsol 8GB USB stick, [Gough] found an entire microSD card. One might be led to think this is a card reader and microSD masquerading as a normal flash drive, but the reality is far different. Instead, the drive contains a Flash memory controller which addresses the microSD card as raw NAND, through test points normally covered up on consumer-grade cards. The drive appears to be manufactured from factory second microSD cards that don’t pass the normal tests to be onsold to the public.

Armed with software obtained through spurious channels, [Gough] is able to dive deeper into the guts of the flash drive. The engineering tools allow the card to be optimised for capacity or speed, and different levels of error correction. It’s even possible to have the flash drive emulate a U3 CD ROM drive for OS installs and other purposes.

It’s a great dive into how USB drives work on a low level, and how the firmware and hardware work together. We’ve seen other flash drive hacks before too – like this simple recovery trick!