SD Card (Secure Digital Card) Standard v1.9

A few weeks ago, a friend and I were trying to write microcontroller code that speaks to an SD (Secure Digital) card. The 2.0 standard is available freely from the SD Card Association. However, the 2.0 standard is pretty complex. The 1.9 standard is much easier to implement, and as far as we can tell, cards still support it. Unfortunately the v1.9 standard has virtually disappeared from the web. We managed to find it on a random personal web site, so I decided to replicate it.

Without further ado, here it is: the SD Card Standard v1.9.

jelson at google mail dot com