NXP Semiconductors LPC24XX UM10237 - Manual (Page 551)

UM10237_4 © NXP B.V. 2009. All rights reserved.
User manual Rev. 04 — 26 August 2009 551 of 792
1. Basic configuration
The SD/MMC is configured using the following registers:
1. Power: In the PCONP register ( Table 4–63 ), set bit PC_MCI.
Remark: On reset, the SD/MMC is disabled (PCMCI = 0).
2. Clock: In PCLK_SEL1 select PCLK_MCI (see Table 4–57 ).
3. Pins: Select SD/MMC pins and their modes in PINSEL0 to PINSEL4 and PINMODE0
to PINMODE4 (see Section 9–5 ).
4. Interrupts: Interrupts are enabled in the VIC using the VICIntEnable register
( Table 7–106 ).
2. Introduction
The Secure Digital and Multimedia Card Interface (MCI) is an interface between the
Advanced Peripheral Bus (APB) system bus and multimedia and/or secure digital memory
cards. It consists of two parts:
• The MCI adapter block provides all functions specific to the Secure Digital/MultiMedia
memory card, such as the clock generation unit, power management control,
command and data transfer.
• The APB interface accesses the MCI adapter registers, and generates interrupt and
DMA request signals.
3. Features of the MCI
The following features are provided by the MCI:
• Conformance to Multimedia Card Specification v2.11.
• Conformance to Secure Digital Memory Card Physical Layer Specification, v0.96.
• Use as a multimedia card bus or a secure digital memory card bus host. It can be
connected to several multimedia cards, or a single secure digital memory card.
• DMA supported through the General Purpose DMA Controller.
4. SD/MMC card interface pin description
UM10237
Chapter 21: LPC24XX SD/MMC card interface
Rev. 04 — 26 August 2009 User manual
Table 481. SD/MMC card interface pin description
Pin Name Type Description
MCICLK Output Clock output
MCICMD Input Command input/output.
MCIDAT[3:0] Output Data lines. Only MCIDAT[0] is used for Multimedia cards.
MCIPWR Output Power Supply Enable for external SD/MMC power supply.