SD Card Write protection
It is relatively unknown that SD/MMC cards also have an electronic write protection system.
Every card has two programmable flags, one for temporary write protection and
one to lock the card forever. Writing these flags is not supported by most SD host devices.
To remedy this, this page presents a program that allows a Linux host to configure the protection register.
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Note that you must be able to access the MMC device directly. Some SD card readers connect over USB and export a Mass
Storage Device (ex. /dev/sda), which cannot be used. My Dell Vostro 1310 laptop shows the card to the operating system as
a MMC device. Most embedded boards, such as the Raspberry Pi, do the same. Therefore, I have compiled a static binary
that you can use on your Raspberry Pi and most other Linux based ARM embedded systems.
You can download it here.