SD_Card_Control - SD-Card Control Program / Using Micro-SD / based…

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Kenji Arai / Mbed 2 deprecated SD_Card_Control

SD-Card Control Program / Using Micro-SD / based on SDCardTest Program (http://mbed.org/users/simon/programs/SDCardTest/gpdz4x/)

Dependencies: mbed SDFileSystem

Please refer following my Notebook page.
/users/kenjiArai/notebook/sd-card-control-new/#

SDFileSystem.cpp@0:3bd1cdc1f3f4, 2010-04-04 (annotated)

Committer:: kenjiArai
Date:: Sun Apr 04 00:42:58 2010 +0000
Revision:: 0:3bd1cdc1f3f4

Who changed what in which revision?

User	Revision	Line number	New contents of line
kenjiArai	0:3bd1cdc1f3f4	1	/* mbed Microcontroller Library - SDFileSystem
kenjiArai	0:3bd1cdc1f3f4	2	* Copyright (c) 2008-2009, sford
kenjiArai	0:3bd1cdc1f3f4	3	*/
kenjiArai	0:3bd1cdc1f3f4	4
kenjiArai	0:3bd1cdc1f3f4	5	// VERY DRAFT CODE! Needs serious rework/refactoring
kenjiArai	0:3bd1cdc1f3f4	6
kenjiArai	0:3bd1cdc1f3f4	7	/* Introduction
kenjiArai	0:3bd1cdc1f3f4	8	* ------------
kenjiArai	0:3bd1cdc1f3f4	9	* SD and MMC cards support a number of interfaces, but common to them all
kenjiArai	0:3bd1cdc1f3f4	10	* is one based on SPI. This is the one I'm implmenting because it means
kenjiArai	0:3bd1cdc1f3f4	11	* it is much more portable even though not so performant, and we already
kenjiArai	0:3bd1cdc1f3f4	12	* have the mbed SPI Interface!
kenjiArai	0:3bd1cdc1f3f4	13	*
kenjiArai	0:3bd1cdc1f3f4	14	* The main reference I'm using is Chapter 7, "SPI Mode" of:
kenjiArai	0:3bd1cdc1f3f4	15	* http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
kenjiArai	0:3bd1cdc1f3f4	16	*
kenjiArai	0:3bd1cdc1f3f4	17	* SPI Startup
kenjiArai	0:3bd1cdc1f3f4	18	* -----------
kenjiArai	0:3bd1cdc1f3f4	19	* The SD card powers up in SD mode. The SPI interface mode is selected by
kenjiArai	0:3bd1cdc1f3f4	20	* asserting CS low and sending the reset command (CMD0). The card will
kenjiArai	0:3bd1cdc1f3f4	21	* respond with a (R1) response.
kenjiArai	0:3bd1cdc1f3f4	22	*
kenjiArai	0:3bd1cdc1f3f4	23	* CMD8 is optionally sent to determine the voltage range supported, and
kenjiArai	0:3bd1cdc1f3f4	24	* indirectly determine whether it is a version 1.x SD/non-SD card or
kenjiArai	0:3bd1cdc1f3f4	25	* version 2.x. I'll just ignore this for now.
kenjiArai	0:3bd1cdc1f3f4	26	*
kenjiArai	0:3bd1cdc1f3f4	27	* ACMD41 is repeatedly issued to initialise the card, until "in idle"
kenjiArai	0:3bd1cdc1f3f4	28	* (bit 0) of the R1 response goes to '0', indicating it is initialised.
kenjiArai	0:3bd1cdc1f3f4	29	*
kenjiArai	0:3bd1cdc1f3f4	30	* You should also indicate whether the host supports High Capicity cards,
kenjiArai	0:3bd1cdc1f3f4	31	* and check whether the card is high capacity - i'll also ignore this
kenjiArai	0:3bd1cdc1f3f4	32	*
kenjiArai	0:3bd1cdc1f3f4	33	* SPI Protocol
kenjiArai	0:3bd1cdc1f3f4	34	* ------------
kenjiArai	0:3bd1cdc1f3f4	35	* The SD SPI protocol is based on transactions made up of 8-bit words, with
kenjiArai	0:3bd1cdc1f3f4	36	* the host starting every bus transaction by asserting the CS signal low. The
kenjiArai	0:3bd1cdc1f3f4	37	* card always responds to commands, data blocks and errors.
kenjiArai	0:3bd1cdc1f3f4	38	*
kenjiArai	0:3bd1cdc1f3f4	39	* The protocol supports a CRC, but by default it is off (except for the
kenjiArai	0:3bd1cdc1f3f4	40	* first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
kenjiArai	0:3bd1cdc1f3f4	41	* I'll leave the CRC off I think!
kenjiArai	0:3bd1cdc1f3f4	42	*
kenjiArai	0:3bd1cdc1f3f4	43	* Standard capacity cards have variable data block sizes, whereas High
kenjiArai	0:3bd1cdc1f3f4	44	* Capacity cards fix the size of data block to 512 bytes. I'll therefore
kenjiArai	0:3bd1cdc1f3f4	45	* just always use the Standard Capacity cards with a block size of 512 bytes.
kenjiArai	0:3bd1cdc1f3f4	46	* This is set with CMD16.
kenjiArai	0:3bd1cdc1f3f4	47	*
kenjiArai	0:3bd1cdc1f3f4	48	* You can read and write single blocks (CMD17, CMD25) or multiple blocks
kenjiArai	0:3bd1cdc1f3f4	49	* (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
kenjiArai	0:3bd1cdc1f3f4	50	* the card gets a read command, it responds with a response token, and then
kenjiArai	0:3bd1cdc1f3f4	51	* a data token or an error.
kenjiArai	0:3bd1cdc1f3f4	52	*
kenjiArai	0:3bd1cdc1f3f4	53	* SPI Command Format
kenjiArai	0:3bd1cdc1f3f4	54	* ------------------
kenjiArai	0:3bd1cdc1f3f4	55	* Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
kenjiArai	0:3bd1cdc1f3f4	56	*
kenjiArai	0:3bd1cdc1f3f4	57	* +---------------+------------+------------+-----------+----------+--------------+
kenjiArai	0:3bd1cdc1f3f4	58	* \| 01 \| cmd[5:0] \| arg[31:24] \| arg[23:16] \| arg[15:8] \| arg[7:0] \| crc[6:0] \| 1 \|
kenjiArai	0:3bd1cdc1f3f4	59	* +---------------+------------+------------+-----------+----------+--------------+
kenjiArai	0:3bd1cdc1f3f4	60	*
kenjiArai	0:3bd1cdc1f3f4	61	* As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
kenjiArai	0:3bd1cdc1f3f4	62	*
kenjiArai	0:3bd1cdc1f3f4	63	* All Application Specific commands shall be preceded with APP_CMD (CMD55).
kenjiArai	0:3bd1cdc1f3f4	64	*
kenjiArai	0:3bd1cdc1f3f4	65	* SPI Response Format
kenjiArai	0:3bd1cdc1f3f4	66	* -------------------
kenjiArai	0:3bd1cdc1f3f4	67	* The main response format (R1) is a status byte (normally zero). Key flags:
kenjiArai	0:3bd1cdc1f3f4	68	* idle - 1 if the card is in an idle state/initialising
kenjiArai	0:3bd1cdc1f3f4	69	* cmd - 1 if an illegal command code was detected
kenjiArai	0:3bd1cdc1f3f4	70	*
kenjiArai	0:3bd1cdc1f3f4	71	* +-------------------------------------------------+
kenjiArai	0:3bd1cdc1f3f4	72	* R1 \| 0 \| arg \| addr \| seq \| crc \| cmd \| erase \| idle \|
kenjiArai	0:3bd1cdc1f3f4	73	* +-------------------------------------------------+
kenjiArai	0:3bd1cdc1f3f4	74	*
kenjiArai	0:3bd1cdc1f3f4	75	* R1b is the same, except it is followed by a busy signal (zeros) until
kenjiArai	0:3bd1cdc1f3f4	76	* the first non-zero byte when it is ready again.
kenjiArai	0:3bd1cdc1f3f4	77	*
kenjiArai	0:3bd1cdc1f3f4	78	* Data Response Token
kenjiArai	0:3bd1cdc1f3f4	79	* -------------------
kenjiArai	0:3bd1cdc1f3f4	80	* Every data block written to the card is acknowledged by a byte
kenjiArai	0:3bd1cdc1f3f4	81	* response token
kenjiArai	0:3bd1cdc1f3f4	82	*
kenjiArai	0:3bd1cdc1f3f4	83	* +----------------------+
kenjiArai	0:3bd1cdc1f3f4	84	* \| xxx \| 0 \| status \| 1 \|
kenjiArai	0:3bd1cdc1f3f4	85	* +----------------------+
kenjiArai	0:3bd1cdc1f3f4	86	* 010 - OK!
kenjiArai	0:3bd1cdc1f3f4	87	* 101 - CRC Error
kenjiArai	0:3bd1cdc1f3f4	88	* 110 - Write Error
kenjiArai	0:3bd1cdc1f3f4	89	*
kenjiArai	0:3bd1cdc1f3f4	90	* Single Block Read and Write
kenjiArai	0:3bd1cdc1f3f4	91	* ---------------------------
kenjiArai	0:3bd1cdc1f3f4	92	*
kenjiArai	0:3bd1cdc1f3f4	93	* Block transfers have a byte header, followed by the data, followed
kenjiArai	0:3bd1cdc1f3f4	94	* by a 16-bit CRC. In our case, the data will always be 512 bytes.
kenjiArai	0:3bd1cdc1f3f4	95	*
kenjiArai	0:3bd1cdc1f3f4	96	* +------+---------+---------+- - - -+---------+-----------+----------+
kenjiArai	0:3bd1cdc1f3f4	97	* \| 0xFE \| data[0] \| data[1] \| \| data[n] \| crc[15:8] \| crc[7:0] \|
kenjiArai	0:3bd1cdc1f3f4	98	* +------+---------+---------+- - - -+---------+-----------+----------+
kenjiArai	0:3bd1cdc1f3f4	99	*/
kenjiArai	0:3bd1cdc1f3f4	100
kenjiArai	0:3bd1cdc1f3f4	101	#include "SDFileSystem.h"
kenjiArai	0:3bd1cdc1f3f4	102
kenjiArai	0:3bd1cdc1f3f4	103	#define SD_COMMAND_TIMEOUT 5000
kenjiArai	0:3bd1cdc1f3f4	104
kenjiArai	0:3bd1cdc1f3f4	105	SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
kenjiArai	0:3bd1cdc1f3f4	106	FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
kenjiArai	0:3bd1cdc1f3f4	107	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	108	}
kenjiArai	0:3bd1cdc1f3f4	109
kenjiArai	0:3bd1cdc1f3f4	110	#define R1_IDLE_STATE (1 << 0)
kenjiArai	0:3bd1cdc1f3f4	111	#define R1_ERASE_RESET (1 << 1)
kenjiArai	0:3bd1cdc1f3f4	112	#define R1_ILLEGAL_COMMAND (1 << 2)
kenjiArai	0:3bd1cdc1f3f4	113	#define R1_COM_CRC_ERROR (1 << 3)
kenjiArai	0:3bd1cdc1f3f4	114	#define R1_ERASE_SEQUENCE_ERROR (1 << 4)
kenjiArai	0:3bd1cdc1f3f4	115	#define R1_ADDRESS_ERROR (1 << 5)
kenjiArai	0:3bd1cdc1f3f4	116	#define R1_PARAMETER_ERROR (1 << 6)
kenjiArai	0:3bd1cdc1f3f4	117
kenjiArai	0:3bd1cdc1f3f4	118	// Types
kenjiArai	0:3bd1cdc1f3f4	119	// - v1.x Standard Capacity
kenjiArai	0:3bd1cdc1f3f4	120	// - v2.x Standard Capacity
kenjiArai	0:3bd1cdc1f3f4	121	// - v2.x High Capacity
kenjiArai	0:3bd1cdc1f3f4	122	// - Not recognised as an SD Card
kenjiArai	0:3bd1cdc1f3f4	123
kenjiArai	0:3bd1cdc1f3f4	124	#define SDCARD_FAIL 0
kenjiArai	0:3bd1cdc1f3f4	125	#define SDCARD_V1 1
kenjiArai	0:3bd1cdc1f3f4	126	#define SDCARD_V2 2
kenjiArai	0:3bd1cdc1f3f4	127	#define SDCARD_V2HC 3
kenjiArai	0:3bd1cdc1f3f4	128
kenjiArai	0:3bd1cdc1f3f4	129	int SDFileSystem::initialise_card() {
kenjiArai	0:3bd1cdc1f3f4	130	// Set to 100kHz for initialisation, and clock card with cs = 1
kenjiArai	0:3bd1cdc1f3f4	131	_spi.frequency(100000);
kenjiArai	0:3bd1cdc1f3f4	132	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	133	for(int i=0; i<16; i++) {
kenjiArai	0:3bd1cdc1f3f4	134	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	135	}
kenjiArai	0:3bd1cdc1f3f4	136
kenjiArai	0:3bd1cdc1f3f4	137	// send CMD0, should return with all zeros except IDLE STATE set (bit 0)
kenjiArai	0:3bd1cdc1f3f4	138	if(_cmd(0, 0) != R1_IDLE_STATE) {
kenjiArai	0:3bd1cdc1f3f4	139	fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n");
kenjiArai	0:3bd1cdc1f3f4	140	return SDCARD_FAIL;
kenjiArai	0:3bd1cdc1f3f4	141	}
kenjiArai	0:3bd1cdc1f3f4	142
kenjiArai	0:3bd1cdc1f3f4	143	// send CMD8 to determine whther it is ver 2.x
kenjiArai	0:3bd1cdc1f3f4	144	int r = _cmd8();
kenjiArai	0:3bd1cdc1f3f4	145	if(r == R1_IDLE_STATE) {
kenjiArai	0:3bd1cdc1f3f4	146	return initialise_card_v2();
kenjiArai	0:3bd1cdc1f3f4	147	} else if(r == (R1_IDLE_STATE \| R1_ILLEGAL_COMMAND)) {
kenjiArai	0:3bd1cdc1f3f4	148	return initialise_card_v1();
kenjiArai	0:3bd1cdc1f3f4	149	} else {
kenjiArai	0:3bd1cdc1f3f4	150	fprintf(stderr, "Not in idle state after sending CMD8 (not an SD card?)\n");
kenjiArai	0:3bd1cdc1f3f4	151	return SDCARD_FAIL;
kenjiArai	0:3bd1cdc1f3f4	152	}
kenjiArai	0:3bd1cdc1f3f4	153	}
kenjiArai	0:3bd1cdc1f3f4	154
kenjiArai	0:3bd1cdc1f3f4	155	int SDFileSystem::initialise_card_v1() {
kenjiArai	0:3bd1cdc1f3f4	156	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
kenjiArai	0:3bd1cdc1f3f4	157	_cmd(55, 0);
kenjiArai	0:3bd1cdc1f3f4	158	if(_cmd(41, 0) == 0) {
kenjiArai	0:3bd1cdc1f3f4	159	return SDCARD_V1;
kenjiArai	0:3bd1cdc1f3f4	160	}
kenjiArai	0:3bd1cdc1f3f4	161	}
kenjiArai	0:3bd1cdc1f3f4	162
kenjiArai	0:3bd1cdc1f3f4	163	fprintf(stderr, "Timeout waiting for v1.x card\n");
kenjiArai	0:3bd1cdc1f3f4	164	return SDCARD_FAIL;
kenjiArai	0:3bd1cdc1f3f4	165	}
kenjiArai	0:3bd1cdc1f3f4	166
kenjiArai	0:3bd1cdc1f3f4	167	int SDFileSystem::initialise_card_v2() {
kenjiArai	0:3bd1cdc1f3f4	168
kenjiArai	0:3bd1cdc1f3f4	169	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
kenjiArai	0:3bd1cdc1f3f4	170	_cmd(55, 0);
kenjiArai	0:3bd1cdc1f3f4	171	if(_cmd(41, 0) == 0) {
kenjiArai	0:3bd1cdc1f3f4	172	_cmd58();
kenjiArai	0:3bd1cdc1f3f4	173	return SDCARD_V2;
kenjiArai	0:3bd1cdc1f3f4	174	}
kenjiArai	0:3bd1cdc1f3f4	175	}
kenjiArai	0:3bd1cdc1f3f4	176
kenjiArai	0:3bd1cdc1f3f4	177	fprintf(stderr, "Timeout waiting for v2.x card\n");
kenjiArai	0:3bd1cdc1f3f4	178	return SDCARD_FAIL;
kenjiArai	0:3bd1cdc1f3f4	179	}
kenjiArai	0:3bd1cdc1f3f4	180
kenjiArai	0:3bd1cdc1f3f4	181	int SDFileSystem::disk_initialize() {
kenjiArai	0:3bd1cdc1f3f4	182
kenjiArai	0:3bd1cdc1f3f4	183	int i = initialise_card();
kenjiArai	0:3bd1cdc1f3f4	184	// printf("init card = %d\n", i);
kenjiArai	0:3bd1cdc1f3f4	185	// printf("OK\n");
kenjiArai	0:3bd1cdc1f3f4	186
kenjiArai	0:3bd1cdc1f3f4	187	_sectors = _sd_sectors();
kenjiArai	0:3bd1cdc1f3f4	188
kenjiArai	0:3bd1cdc1f3f4	189	// Set block length to 512 (CMD16)
kenjiArai	0:3bd1cdc1f3f4	190	if(_cmd(16, 512) != 0) {
kenjiArai	0:3bd1cdc1f3f4	191	fprintf(stderr, "Set 512-byte block timed out\n");
kenjiArai	0:3bd1cdc1f3f4	192	return 1;
kenjiArai	0:3bd1cdc1f3f4	193	}
kenjiArai	0:3bd1cdc1f3f4	194
kenjiArai	0:3bd1cdc1f3f4	195	_spi.frequency(1000000); // Set to 1MHz for data transfer
kenjiArai	0:3bd1cdc1f3f4	196	return 0;
kenjiArai	0:3bd1cdc1f3f4	197	}
kenjiArai	0:3bd1cdc1f3f4	198
kenjiArai	0:3bd1cdc1f3f4	199	int SDFileSystem::disk_write(const char *buffer, int block_number) {
kenjiArai	0:3bd1cdc1f3f4	200	// set write address for single block (CMD24)
kenjiArai	0:3bd1cdc1f3f4	201	if(_cmd(24, block_number * 512) != 0) {
kenjiArai	0:3bd1cdc1f3f4	202	return 1;
kenjiArai	0:3bd1cdc1f3f4	203	}
kenjiArai	0:3bd1cdc1f3f4	204
kenjiArai	0:3bd1cdc1f3f4	205	// send the data block
kenjiArai	0:3bd1cdc1f3f4	206	_write(buffer, 512);
kenjiArai	0:3bd1cdc1f3f4	207	return 0;
kenjiArai	0:3bd1cdc1f3f4	208	}
kenjiArai	0:3bd1cdc1f3f4	209
kenjiArai	0:3bd1cdc1f3f4	210	int SDFileSystem::disk_read(char *buffer, int block_number) {
kenjiArai	0:3bd1cdc1f3f4	211	// set read address for single block (CMD17)
kenjiArai	0:3bd1cdc1f3f4	212	if(_cmd(17, block_number * 512) != 0) {
kenjiArai	0:3bd1cdc1f3f4	213	return 1;
kenjiArai	0:3bd1cdc1f3f4	214	}
kenjiArai	0:3bd1cdc1f3f4	215
kenjiArai	0:3bd1cdc1f3f4	216	// receive the data
kenjiArai	0:3bd1cdc1f3f4	217	_read(buffer, 512);
kenjiArai	0:3bd1cdc1f3f4	218	return 0;
kenjiArai	0:3bd1cdc1f3f4	219	}
kenjiArai	0:3bd1cdc1f3f4	220
kenjiArai	0:3bd1cdc1f3f4	221	int SDFileSystem::disk_status() { return 0; }
kenjiArai	0:3bd1cdc1f3f4	222	int SDFileSystem::disk_sync() { return 0; }
kenjiArai	0:3bd1cdc1f3f4	223	int SDFileSystem::disk_sectors() { return _sectors; }
kenjiArai	0:3bd1cdc1f3f4	224
kenjiArai	0:3bd1cdc1f3f4	225	// PRIVATE FUNCTIONS
kenjiArai	0:3bd1cdc1f3f4	226
kenjiArai	0:3bd1cdc1f3f4	227	int SDFileSystem::_cmd(int cmd, int arg) {
kenjiArai	0:3bd1cdc1f3f4	228	_cs = 0;
kenjiArai	0:3bd1cdc1f3f4	229
kenjiArai	0:3bd1cdc1f3f4	230	// send a command
kenjiArai	0:3bd1cdc1f3f4	231	_spi.write(0x40 \| cmd);
kenjiArai	0:3bd1cdc1f3f4	232	_spi.write(arg >> 24);
kenjiArai	0:3bd1cdc1f3f4	233	_spi.write(arg >> 16);
kenjiArai	0:3bd1cdc1f3f4	234	_spi.write(arg >> 8);
kenjiArai	0:3bd1cdc1f3f4	235	_spi.write(arg >> 0);
kenjiArai	0:3bd1cdc1f3f4	236	_spi.write(0x95);
kenjiArai	0:3bd1cdc1f3f4	237
kenjiArai	0:3bd1cdc1f3f4	238	// wait for the repsonse (response[7] == 0)
kenjiArai	0:3bd1cdc1f3f4	239	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
kenjiArai	0:3bd1cdc1f3f4	240	int response = _spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	241	if(!(response & 0x80)) {
kenjiArai	0:3bd1cdc1f3f4	242	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	243	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	244	return response;
kenjiArai	0:3bd1cdc1f3f4	245	}
kenjiArai	0:3bd1cdc1f3f4	246	}
kenjiArai	0:3bd1cdc1f3f4	247	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	248	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	249	return -1; // timeout
kenjiArai	0:3bd1cdc1f3f4	250	}
kenjiArai	0:3bd1cdc1f3f4	251	int SDFileSystem::_cmdx(int cmd, int arg) {
kenjiArai	0:3bd1cdc1f3f4	252	_cs = 0;
kenjiArai	0:3bd1cdc1f3f4	253
kenjiArai	0:3bd1cdc1f3f4	254	// send a command
kenjiArai	0:3bd1cdc1f3f4	255	_spi.write(0x40 \| cmd);
kenjiArai	0:3bd1cdc1f3f4	256	_spi.write(arg >> 24);
kenjiArai	0:3bd1cdc1f3f4	257	_spi.write(arg >> 16);
kenjiArai	0:3bd1cdc1f3f4	258	_spi.write(arg >> 8);
kenjiArai	0:3bd1cdc1f3f4	259	_spi.write(arg >> 0);
kenjiArai	0:3bd1cdc1f3f4	260	_spi.write(0x95);
kenjiArai	0:3bd1cdc1f3f4	261
kenjiArai	0:3bd1cdc1f3f4	262	// wait for the repsonse (response[7] == 0)
kenjiArai	0:3bd1cdc1f3f4	263	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
kenjiArai	0:3bd1cdc1f3f4	264	int response = _spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	265	if(!(response & 0x80)) {
kenjiArai	0:3bd1cdc1f3f4	266	return response;
kenjiArai	0:3bd1cdc1f3f4	267	}
kenjiArai	0:3bd1cdc1f3f4	268	}
kenjiArai	0:3bd1cdc1f3f4	269	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	270	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	271	return -1; // timeout
kenjiArai	0:3bd1cdc1f3f4	272	}
kenjiArai	0:3bd1cdc1f3f4	273
kenjiArai	0:3bd1cdc1f3f4	274
kenjiArai	0:3bd1cdc1f3f4	275	int SDFileSystem::_cmd58() {
kenjiArai	0:3bd1cdc1f3f4	276	_cs = 0;
kenjiArai	0:3bd1cdc1f3f4	277	int arg = 0;
kenjiArai	0:3bd1cdc1f3f4	278
kenjiArai	0:3bd1cdc1f3f4	279	// send a command
kenjiArai	0:3bd1cdc1f3f4	280	_spi.write(0x40 \| 58);
kenjiArai	0:3bd1cdc1f3f4	281	_spi.write(arg >> 24);
kenjiArai	0:3bd1cdc1f3f4	282	_spi.write(arg >> 16);
kenjiArai	0:3bd1cdc1f3f4	283	_spi.write(arg >> 8);
kenjiArai	0:3bd1cdc1f3f4	284	_spi.write(arg >> 0);
kenjiArai	0:3bd1cdc1f3f4	285	_spi.write(0x95);
kenjiArai	0:3bd1cdc1f3f4	286
kenjiArai	0:3bd1cdc1f3f4	287	// wait for the repsonse (response[7] == 0)
kenjiArai	0:3bd1cdc1f3f4	288	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
kenjiArai	0:3bd1cdc1f3f4	289	int response = _spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	290	if(!(response & 0x80)) {
kenjiArai	0:3bd1cdc1f3f4	291	int ocr = _spi.write(0xFF) << 24;
kenjiArai	0:3bd1cdc1f3f4	292	ocr \|= _spi.write(0xFF) << 16;
kenjiArai	0:3bd1cdc1f3f4	293	ocr \|= _spi.write(0xFF) << 8;
kenjiArai	0:3bd1cdc1f3f4	294	ocr \|= _spi.write(0xFF) << 0;
kenjiArai	0:3bd1cdc1f3f4	295	// printf("OCR = 0x%08X\n", ocr);
kenjiArai	0:3bd1cdc1f3f4	296	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	297	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	298	return response;
kenjiArai	0:3bd1cdc1f3f4	299	}
kenjiArai	0:3bd1cdc1f3f4	300	}
kenjiArai	0:3bd1cdc1f3f4	301	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	302	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	303	return -1; // timeout
kenjiArai	0:3bd1cdc1f3f4	304	}
kenjiArai	0:3bd1cdc1f3f4	305
kenjiArai	0:3bd1cdc1f3f4	306	int SDFileSystem::_cmd8() {
kenjiArai	0:3bd1cdc1f3f4	307	_cs = 0;
kenjiArai	0:3bd1cdc1f3f4	308
kenjiArai	0:3bd1cdc1f3f4	309	// send a command
kenjiArai	0:3bd1cdc1f3f4	310	_spi.write(0x40 \| 8); // CMD8
kenjiArai	0:3bd1cdc1f3f4	311	_spi.write(0x00); // reserved
kenjiArai	0:3bd1cdc1f3f4	312	_spi.write(0x00); // reserved
kenjiArai	0:3bd1cdc1f3f4	313	_spi.write(0x01); // 3.3v
kenjiArai	0:3bd1cdc1f3f4	314	_spi.write(0xAA); // check pattern
kenjiArai	0:3bd1cdc1f3f4	315	_spi.write(0x87); // crc
kenjiArai	0:3bd1cdc1f3f4	316
kenjiArai	0:3bd1cdc1f3f4	317	// wait for the repsonse (response[7] == 0)
kenjiArai	0:3bd1cdc1f3f4	318	for(int i=0; i<SD_COMMAND_TIMEOUT * 1000; i++) {
kenjiArai	0:3bd1cdc1f3f4	319	char response[5];
kenjiArai	0:3bd1cdc1f3f4	320	response[0] = _spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	321	if(!(response[0] & 0x80)) {
kenjiArai	0:3bd1cdc1f3f4	322	for(int j=1; j<5; j++) {
kenjiArai	0:3bd1cdc1f3f4	323	response[i] = _spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	324	}
kenjiArai	0:3bd1cdc1f3f4	325	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	326	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	327	return response[0];
kenjiArai	0:3bd1cdc1f3f4	328	}
kenjiArai	0:3bd1cdc1f3f4	329	}
kenjiArai	0:3bd1cdc1f3f4	330	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	331	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	332	return -1; // timeout
kenjiArai	0:3bd1cdc1f3f4	333	}
kenjiArai	0:3bd1cdc1f3f4	334
kenjiArai	0:3bd1cdc1f3f4	335	int SDFileSystem::_read(char *buffer, int length) {
kenjiArai	0:3bd1cdc1f3f4	336	_cs = 0;
kenjiArai	0:3bd1cdc1f3f4	337
kenjiArai	0:3bd1cdc1f3f4	338	// read until start byte (0xFF)
kenjiArai	0:3bd1cdc1f3f4	339	while(_spi.write(0xFF) != 0xFE);
kenjiArai	0:3bd1cdc1f3f4	340
kenjiArai	0:3bd1cdc1f3f4	341	// read data
kenjiArai	0:3bd1cdc1f3f4	342	for(int i=0; i<length; i++) {
kenjiArai	0:3bd1cdc1f3f4	343	buffer[i] = _spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	344	}
kenjiArai	0:3bd1cdc1f3f4	345	_spi.write(0xFF); // checksum
kenjiArai	0:3bd1cdc1f3f4	346	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	347
kenjiArai	0:3bd1cdc1f3f4	348	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	349	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	350	return 0;
kenjiArai	0:3bd1cdc1f3f4	351	}
kenjiArai	0:3bd1cdc1f3f4	352
kenjiArai	0:3bd1cdc1f3f4	353	int SDFileSystem::_write(const char *buffer, int length) {
kenjiArai	0:3bd1cdc1f3f4	354	_cs = 0;
kenjiArai	0:3bd1cdc1f3f4	355
kenjiArai	0:3bd1cdc1f3f4	356	// indicate start of block
kenjiArai	0:3bd1cdc1f3f4	357	_spi.write(0xFE);
kenjiArai	0:3bd1cdc1f3f4	358
kenjiArai	0:3bd1cdc1f3f4	359	// write the data
kenjiArai	0:3bd1cdc1f3f4	360	for(int i=0; i<length; i++) {
kenjiArai	0:3bd1cdc1f3f4	361	_spi.write(buffer[i]);
kenjiArai	0:3bd1cdc1f3f4	362	}
kenjiArai	0:3bd1cdc1f3f4	363
kenjiArai	0:3bd1cdc1f3f4	364	// write the checksum
kenjiArai	0:3bd1cdc1f3f4	365	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	366	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	367
kenjiArai	0:3bd1cdc1f3f4	368	// check the repsonse token
kenjiArai	0:3bd1cdc1f3f4	369	if((_spi.write(0xFF) & 0x1F) != 0x05) {
kenjiArai	0:3bd1cdc1f3f4	370	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	371	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	372	return 1;
kenjiArai	0:3bd1cdc1f3f4	373	}
kenjiArai	0:3bd1cdc1f3f4	374
kenjiArai	0:3bd1cdc1f3f4	375	// wait for write to finish
kenjiArai	0:3bd1cdc1f3f4	376	while(_spi.write(0xFF) == 0);
kenjiArai	0:3bd1cdc1f3f4	377
kenjiArai	0:3bd1cdc1f3f4	378	_cs = 1;
kenjiArai	0:3bd1cdc1f3f4	379	_spi.write(0xFF);
kenjiArai	0:3bd1cdc1f3f4	380	return 0;
kenjiArai	0:3bd1cdc1f3f4	381	}
kenjiArai	0:3bd1cdc1f3f4	382
kenjiArai	0:3bd1cdc1f3f4	383	static int ext_bits(char *data, int msb, int lsb) {
kenjiArai	0:3bd1cdc1f3f4	384	int bits = 0;
kenjiArai	0:3bd1cdc1f3f4	385	int size = 1 + msb - lsb;
kenjiArai	0:3bd1cdc1f3f4	386	for(int i=0; i<size; i++) {
kenjiArai	0:3bd1cdc1f3f4	387	int position = lsb + i;
kenjiArai	0:3bd1cdc1f3f4	388	int byte = 15 - (position >> 3);
kenjiArai	0:3bd1cdc1f3f4	389	int bit = position & 0x7;
kenjiArai	0:3bd1cdc1f3f4	390	int value = (data[byte] >> bit) & 1;
kenjiArai	0:3bd1cdc1f3f4	391	bits \|= value << i;
kenjiArai	0:3bd1cdc1f3f4	392	}
kenjiArai	0:3bd1cdc1f3f4	393	return bits;
kenjiArai	0:3bd1cdc1f3f4	394	}
kenjiArai	0:3bd1cdc1f3f4	395
kenjiArai	0:3bd1cdc1f3f4	396	int SDFileSystem::_sd_sectors() {
kenjiArai	0:3bd1cdc1f3f4	397
kenjiArai	0:3bd1cdc1f3f4	398	// CMD9, Response R2 (R1 byte + 16-byte block read)
kenjiArai	0:3bd1cdc1f3f4	399	if(_cmdx(9, 0) != 0) {
kenjiArai	0:3bd1cdc1f3f4	400	fprintf(stderr, "Didn't get a response from the disk\n");
kenjiArai	0:3bd1cdc1f3f4	401	return 0;
kenjiArai	0:3bd1cdc1f3f4	402	}
kenjiArai	0:3bd1cdc1f3f4	403
kenjiArai	0:3bd1cdc1f3f4	404	char csd[16];
kenjiArai	0:3bd1cdc1f3f4	405	if(_read(csd, 16) != 0) {
kenjiArai	0:3bd1cdc1f3f4	406	fprintf(stderr, "Couldn't read csd response from disk\n");
kenjiArai	0:3bd1cdc1f3f4	407	return 0;
kenjiArai	0:3bd1cdc1f3f4	408	}
kenjiArai	0:3bd1cdc1f3f4	409
kenjiArai	0:3bd1cdc1f3f4	410	// csd_structure : csd[127:126]
kenjiArai	0:3bd1cdc1f3f4	411	// c_size : csd[73:62]
kenjiArai	0:3bd1cdc1f3f4	412	// c_size_mult : csd[49:47]
kenjiArai	0:3bd1cdc1f3f4	413	// read_bl_len : csd[83:80] - the maximum read block length
kenjiArai	0:3bd1cdc1f3f4	414
kenjiArai	0:3bd1cdc1f3f4	415	int csd_structure = ext_bits(csd, 127, 126);
kenjiArai	0:3bd1cdc1f3f4	416	int c_size = ext_bits(csd, 73, 62);
kenjiArai	0:3bd1cdc1f3f4	417	int c_size_mult = ext_bits(csd, 49, 47);
kenjiArai	0:3bd1cdc1f3f4	418	int read_bl_len = ext_bits(csd, 83, 80);
kenjiArai	0:3bd1cdc1f3f4	419
kenjiArai	0:3bd1cdc1f3f4	420	// printf("CSD_STRUCT = %d\n", csd_structure);
kenjiArai	0:3bd1cdc1f3f4	421
kenjiArai	0:3bd1cdc1f3f4	422	if(csd_structure != 0) {
kenjiArai	0:3bd1cdc1f3f4	423	fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures\n");
kenjiArai	0:3bd1cdc1f3f4	424	return 0;
kenjiArai	0:3bd1cdc1f3f4	425	}
kenjiArai	0:3bd1cdc1f3f4	426
kenjiArai	0:3bd1cdc1f3f4	427	// memory capacity = BLOCKNR * BLOCK_LEN
kenjiArai	0:3bd1cdc1f3f4	428	// where
kenjiArai	0:3bd1cdc1f3f4	429	// BLOCKNR = (C_SIZE+1) * MULT
kenjiArai	0:3bd1cdc1f3f4	430	// MULT = 2^(C_SIZE_MULT+2) (C_SIZE_MULT < 8)
kenjiArai	0:3bd1cdc1f3f4	431	// BLOCK_LEN = 2^READ_BL_LEN, (READ_BL_LEN < 12)
kenjiArai	0:3bd1cdc1f3f4	432
kenjiArai	0:3bd1cdc1f3f4	433	int block_len = 1 << read_bl_len;
kenjiArai	0:3bd1cdc1f3f4	434	int mult = 1 << (c_size_mult + 2);
kenjiArai	0:3bd1cdc1f3f4	435	int blocknr = (c_size + 1) * mult;
kenjiArai	0:3bd1cdc1f3f4	436	int capacity = blocknr * block_len;
kenjiArai	0:3bd1cdc1f3f4	437
kenjiArai	0:3bd1cdc1f3f4	438	int blocks = capacity / 512;
kenjiArai	0:3bd1cdc1f3f4	439
kenjiArai	0:3bd1cdc1f3f4	440	return blocks;
kenjiArai	0:3bd1cdc1f3f4	441	}

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	04 Apr 2010
Imports:	396
Forks:	0
Commits:	8
Dependents:	0
Dependencies:	2
Followers:	4

The code in this repository is Apache licensed.

SDFileSystem.cpp@0:3bd1cdc1f3f4, 2010-04-04 (annotated)

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