library

/*! \file mmc.h \brief MultiMedia and SD Flash Card Interface. */
//*****************************************************************************
//
// File Name    : 'mmc.h'
// Title                : MultiMedia and SD Flash Card Interface
// Author               : Pascal Stang - Copyright (C) 2004
// Created              : 2004.09.22
// Revised              : 2004.09.22
// Version              : 0.1
// Target MCU   : Atmel AVR Series
// Editor Tabs  : 4
//
///     \ingroup driver_hw
/// \defgroup mmc MultiMedia and SD Flash Card Interface (mmc.c)
/// \code #include "mmc.h" \endcode
/// \par Description
///             This library offers some simple functions which can be used
///             to read and write data on a MultiMedia or SecureDigital (SD) Flash
///             Card.  Although MM and SD Cards are designed to operate with their own
///             special bus wiring and protocols, both types of cards also provide a
///             simple SPI-like interface mode which is exceptionally useful when 
///             attempting to use the cards in embedded systems.
///
/// \par Wiring
///             To work with this library, the card must be wired to the SPI port of
///             the Atmel microcontroller as described below.  Typical cards can
///             operate at up to 25MHz maximum SPI clock rate (thus faster than most
///             AVR's maximum SPI clock rate).
/// <pre>
///           _________________
///          /  1 2 3 4 5 6 78 |        <- view of MMC/SD card looking at contacts
///         / 9                |        Pins 8 and 9 are present only on SD cards
///         |    MMC/SD Card   |
///         |                  |
///         /\/\/\/\/\/\/\/\/\/\
///         1 - CS   (chip select)          - wire to any available I/O pin(*)
///         2 - DIN  (data in, card<-host)  - wire to SPI MOSI pin
///         3 - VSS  (ground)               - wire to ground
///         4 - VDD  (power, 3.3V only?)    - wire to power (MIGHT BE 3.3V ONLY!)
///         5 - SCLK (data clock)           - wire to SPI SCK pin
///         6 - VSS  (ground)               - wire to ground
///         7 - DOUT (data out, card->host) - wire to SPI MISO pin
///
///         (*) you must define this chip select I/O pin in mmcconf.h
/// </pre>
/// \note This code is currently below version 1.0, and therefore is considered
/// to be lacking in some functionality or documentation, or may not be fully
/// tested.  Nonetheless, you can expect most functions to work.
//
// This code is distributed under the GNU Public License
//              which can be found at http://www.gnu.org/licenses/gpl.txt
//
//*****************************************************************************
//@{

#ifndef MMC_H
#define MMC_H

#include "global.h"

// constants/macros/typdefs
// MMC commands (taken from sandisk MMC reference)
#define MMC_GO_IDLE_STATE                       0                ///< initialize card to SPI-type access
#define MMC_SEND_OP_COND                        1               ///< set card operational mode
#define MMC_SEND_CSD                            9               ///< get card's CSD
#define MMC_SEND_CID                            10              ///< get card's CID
#define MMC_SEND_STATUS                         13
#define MMC_SET_BLOCKLEN                        16              ///< Set number of bytes to transfer per block
#define MMC_READ_SINGLE_BLOCK           17              ///< read a block
#define MMC_WRITE_BLOCK                         24              ///< write a block
#define MMC_PROGRAM_CSD                         27
#define MMC_SET_WRITE_PROT                      28
#define MMC_CLR_WRITE_PROT                      29
#define MMC_SEND_WRITE_PROT                     30
#define MMC_TAG_SECTOR_START            32
#define MMC_TAG_SECTOR_END                      33
#define MMC_UNTAG_SECTOR                        34
#define MMC_TAG_ERASE_GROUP_START       35              ///< Sets beginning of erase group (mass erase)
#define MMC_TAG_ERARE_GROUP_END         36              ///< Sets end of erase group (mass erase)
#define MMC_UNTAG_ERASE_GROUP           37              ///< Untag (unset) erase group (mass erase)
#define MMC_ERASE                                       38              ///< Perform block/mass erase
#define MMC_CRC_ON_OFF                          59              ///< Turns CRC check on/off
// R1 Response bit-defines
#define MMC_R1_BUSY                                     0x80    ///< R1 response: bit indicates card is busy
#define MMC_R1_PARAMETER                        0x40
#define MMC_R1_ADDRESS                          0x20
#define MMC_R1_ERASE_SEQ                        0x10
#define MMC_R1_COM_CRC                          0x08
#define MMC_R1_ILLEGAL_COM                      0x04
#define MMC_R1_ERASE_RESET                      0x02
#define MMC_R1_IDLE_STATE                       0x01
// Data Start tokens
#define MMC_STARTBLOCK_READ                     0xFE    ///< when received from card, indicates that a block of data will follow
#define MMC_STARTBLOCK_WRITE            0xFE    ///< when sent to card, indicates that a block of data will follow
#define MMC_STARTBLOCK_MWRITE           0xFC
// Data Stop tokens
#define MMC_STOPTRAN_WRITE                      0xFD
// Data Error Token values
#define MMC_DE_MASK                                     0x1F
#define MMC_DE_ERROR                            0x01
#define MMC_DE_CC_ERROR                         0x02
#define MMC_DE_ECC_FAIL                         0x04
#define MMC_DE_OUT_OF_RANGE                     0x04
#define MMC_DE_CARD_LOCKED                      0x04
// Data Response Token values
#define MMC_DR_MASK                                     0x1F
#define MMC_DR_ACCEPT                           0x05
#define MMC_DR_REJECT_CRC                       0x0B
#define MMC_DR_REJECT_WRITE_ERROR       0x0D

// functions

//! Initialize AVR<->MMC hardware interface.
/// Prepares hardware for MMC access.
void mmcInit(void);

//! Initialize the card and prepare it for use.
/// Returns zero if successful.
u08 mmcReset(void);

//! Send card an MMC command.
/// Returns R1 result code.
u08 mmcSendCommand(u08 cmd, u32 arg);

//! Read 512-byte sector from card to buffer
/// Returns zero if successful.
u08 mmcRead(u32 sector, u08* buffer);

//! Write 512-byte sector from buffer to card
/// Returns zero if successful.
u08 mmcWrite(u32 sector, u08* buffer);

//! Internal command function.
/// Issues a generic MMC command as specified by cmd and arg.
u08 mmcCommand(u08 cmd, u32 arg);

#endif
//@}