> For the complete documentation index, see [llms.txt](https://open-rt.gitbook.io/open-surfacert/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://open-rt.gitbook.io/open-surfacert/surface-rt/hardware/components/mmc/1-msd-card.md).

# 1 - μSD Card

## GPIOs

Power: D7\
Card Detect: I5\
WriteProtect: T3

![Hotplug GPIO in action](https://2395005476-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-MJQb34R_xPz0ll0scbM%2F-MdrZkxitMKZj-_D7e3f%2F-Mdra4nUXmghD23tIHGf%2FSD_Card_hotplug.png?alt=media\&token=1ed3d67e-edb0-470d-8406-45c967588ce8)

## Power

uSD Card is powered by PMIC LowDropout regaultor 5 (LDO5)\
It switches between 3.3V and 1.8V.