SD Card Protocol

 Although SD memory cards can be used for a wide variety of storage purposes, they are most commonly used in digital cameras. These high-speed storage devices have become the de facto standard for a multitude of electronic devices.

SD memory cards come in three different classes based on storage capacity. The standard format has storage capacity up to 2 GB and comes in three different sizes: SD (32 mm by 24 mm by 2.1 mm), miniSD (21.5 mm by 20 mm by 1.4 mm) and microSD (15 mm by 11 mm by 1.0 mm). The SD high-capacity, or SDHC, format has storage capacity between 4 GB and 32 GB and comes in three different sizes: SDHC, miniSDHC and microSDHC. The SD extended capacity, or SDXC, cards have the greatest storage capacity, ranging from 32 GB to 2 TB. SDXC cards come in two different sizes: SDXC and microSDXC.

 

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