Secure Digital (SD) memory cards are popular storage devices used in consumer electronics. This document explains the fundamentals of SD cards, including their serial and random access capabilities, form factors, and communication protocols.
The guide specifically covers interfacing these cards with Analog Devices Blackfin processors. It details two primary methods: using the Serial Peripheral Interface (SPI) port for a simpler setup or utilizing the Parallel Peripheral Interface (PPI) and Asynchronous Memory Interface (AMI) for full feature support.
Certain Blackfin processors have on-chip SD support; refer to the processor selection guide for specific details.
SD cards support a serial mode compatible with SPI and a parallel mode commonly referred to as SD mode.
The maximum operating clock frequency can go up to 25 MHz in default mode or up to 50 MHz in high-speed mode.