chan_fatfs - test

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test

chan_fs/diskio.c@0:c1253c12d4bc, 2010-02-21 (annotated)

Committer:: emh203
Date:: Sun Feb 21 02:45:09 2010 +0000
Revision:: 0:c1253c12d4bc

Who changed what in which revision?

User	Revision	Line number	New contents of line
emh203	0:c1253c12d4bc	1	/-----------------------------------------------------------------------/
emh203	0:c1253c12d4bc	2	/* Low level disk I/O module skeleton for FatFs (C)ChaN, 2007 */
emh203	0:c1253c12d4bc	3	/-----------------------------------------------------------------------/
emh203	0:c1253c12d4bc	4	/* This is a stub disk I/O module that acts as front end of the existing */
emh203	0:c1253c12d4bc	5	/* disk I/O modules and attach it to FatFs module with common interface. */
emh203	0:c1253c12d4bc	6	/-----------------------------------------------------------------------/
emh203	0:c1253c12d4bc	7
emh203	0:c1253c12d4bc	8	#include "diskio.h"
emh203	0:c1253c12d4bc	9	#include "mbed.h"
emh203	0:c1253c12d4bc	10
emh203	0:c1253c12d4bc	11
emh203	0:c1253c12d4bc	12	//******************************************************************************************************************
emh203	0:c1253c12d4bc	13	// MBED SPI/CS Select functions.... Modify for your layout.
emh203	0:c1253c12d4bc	14	//**************************************************************************************
emh203	0:c1253c12d4bc	15
emh203	0:c1253c12d4bc	16	SPI _spi(p5, p6, p7); // mosi, miso, sclk
emh203	0:c1253c12d4bc	17	DigitalOut _cs(p8);
emh203	0:c1253c12d4bc	18
emh203	0:c1253c12d4bc	19	//******************************************************************************************************************
emh203	0:c1253c12d4bc	20	// Low Level Sector Access Function Prototypes('C' Castrated versions of Simon Ford's C++ MBED SDFileSystem class
emh203	0:c1253c12d4bc	21	//******************************************************************************************************************
emh203	0:c1253c12d4bc	22	int _cmd(int cmd, int arg);
emh203	0:c1253c12d4bc	23	int _read(BYTE *buffer, int length);
emh203	0:c1253c12d4bc	24	int _write(BYTE *buffer, int length);
emh203	0:c1253c12d4bc	25	int ext_bits(BYTE *data, int msb, int lsb);
emh203	0:c1253c12d4bc	26	int _sd_sectors();
emh203	0:c1253c12d4bc	27	int _sectors;
emh203	0:c1253c12d4bc	28
emh203	0:c1253c12d4bc	29	#define SD_COMMAND_TIMEOUT 5000
emh203	0:c1253c12d4bc	30
emh203	0:c1253c12d4bc	31
emh203	0:c1253c12d4bc	32	//******************************************************************************************************************
emh203	0:c1253c12d4bc	33	// Sector Access functions for CHAN FatFs
emh203	0:c1253c12d4bc	34	//******************************************************************************************************************
emh203	0:c1253c12d4bc	35
emh203	0:c1253c12d4bc	36	DRESULT disk_ioctl (
emh203	0:c1253c12d4bc	37	BYTE drv, /* Physical drive nmuber (0..) */
emh203	0:c1253c12d4bc	38	BYTE ctrl, /* Control code */
emh203	0:c1253c12d4bc	39	void buff / Buffer to send/receive control data */
emh203	0:c1253c12d4bc	40	)
emh203	0:c1253c12d4bc	41	{
emh203	0:c1253c12d4bc	42	DRESULT res;
emh203	0:c1253c12d4bc	43
emh203	0:c1253c12d4bc	44	switch(ctrl)
emh203	0:c1253c12d4bc	45	{
emh203	0:c1253c12d4bc	46	case CTRL_SYNC:
emh203	0:c1253c12d4bc	47	res = RES_OK;
emh203	0:c1253c12d4bc	48	break;
emh203	0:c1253c12d4bc	49
emh203	0:c1253c12d4bc	50	case GET_SECTOR_SIZE:
emh203	0:c1253c12d4bc	51	res = RES_OK;
emh203	0:c1253c12d4bc	52	(WORD )buff = 512;
emh203	0:c1253c12d4bc	53	break;
emh203	0:c1253c12d4bc	54
emh203	0:c1253c12d4bc	55	case GET_SECTOR_COUNT:
emh203	0:c1253c12d4bc	56	res = RES_OK;
emh203	0:c1253c12d4bc	57	(DWORD )buff = (WORD)_sd_sectors();
emh203	0:c1253c12d4bc	58	break;
emh203	0:c1253c12d4bc	59
emh203	0:c1253c12d4bc	60	case GET_BLOCK_SIZE:
emh203	0:c1253c12d4bc	61	res = RES_OK;
emh203	0:c1253c12d4bc	62	(DWORD )buff = 1;
emh203	0:c1253c12d4bc	63	break;
emh203	0:c1253c12d4bc	64
emh203	0:c1253c12d4bc	65	default:
emh203	0:c1253c12d4bc	66	res = RES_OK;
emh203	0:c1253c12d4bc	67	break;
emh203	0:c1253c12d4bc	68	}
emh203	0:c1253c12d4bc	69	return res;
emh203	0:c1253c12d4bc	70	}
emh203	0:c1253c12d4bc	71
emh203	0:c1253c12d4bc	72	DSTATUS disk_initialize(BYTE Drive) {
emh203	0:c1253c12d4bc	73
emh203	0:c1253c12d4bc	74	_spi.frequency(100000); // Set to 100kHz for initialisation
emh203	0:c1253c12d4bc	75
emh203	0:c1253c12d4bc	76	// Initialise the card by clocking it a bit (cs = 1)
emh203	0:c1253c12d4bc	77	for(int i=0; i<16; i++) {
emh203	0:c1253c12d4bc	78	_spi.write(0xFF);
emh203	0:c1253c12d4bc	79	}
emh203	0:c1253c12d4bc	80
emh203	0:c1253c12d4bc	81	// send CMD0, should return with all zeros except IDLE STATE set (bit 0)
emh203	0:c1253c12d4bc	82	if(_cmd(0, 0) != 0x01) {
emh203	0:c1253c12d4bc	83	fprintf(stderr, "Not in idle state\n");
emh203	0:c1253c12d4bc	84	return STA_NOINIT;
emh203	0:c1253c12d4bc	85	}
emh203	0:c1253c12d4bc	86
emh203	0:c1253c12d4bc	87	// ACMD41 to give host capacity support (repeat until not busy)
emh203	0:c1253c12d4bc	88	// ACMD41 is application specific command, so we send APP_CMD (CMD55) beforehand
emh203	0:c1253c12d4bc	89	for(int i=0;; i++) {
emh203	0:c1253c12d4bc	90	_cmd(55, 0);
emh203	0:c1253c12d4bc	91	int response = _cmd(41, 0);
emh203	0:c1253c12d4bc	92	if(response == 0) {
emh203	0:c1253c12d4bc	93	break;
emh203	0:c1253c12d4bc	94	} else if(i > SD_COMMAND_TIMEOUT) {
emh203	0:c1253c12d4bc	95	fprintf(stderr, "Timeout waiting for card\n");
emh203	0:c1253c12d4bc	96	return STA_NOINIT;
emh203	0:c1253c12d4bc	97	}
emh203	0:c1253c12d4bc	98	}
emh203	0:c1253c12d4bc	99
emh203	0:c1253c12d4bc	100	_sectors = _sd_sectors();
emh203	0:c1253c12d4bc	101
emh203	0:c1253c12d4bc	102	// Set block length to 512 (CMD16)
emh203	0:c1253c12d4bc	103	if(_cmd(16, 512) != 0) {
emh203	0:c1253c12d4bc	104	fprintf(stderr, "Set block timeout\n");
emh203	0:c1253c12d4bc	105	return STA_NOINIT;
emh203	0:c1253c12d4bc	106	}
emh203	0:c1253c12d4bc	107
emh203	0:c1253c12d4bc	108	_spi.frequency(10000000); // Set to 10MHz for data transfer
emh203	0:c1253c12d4bc	109	return 0;
emh203	0:c1253c12d4bc	110	}
emh203	0:c1253c12d4bc	111
emh203	0:c1253c12d4bc	112	DRESULT disk_write(BYTE Drive,const BYTE * Buffer, DWORD SectorNumber, BYTE SectorCount)
emh203	0:c1253c12d4bc	113	{
emh203	0:c1253c12d4bc	114	BYTE i;
emh203	0:c1253c12d4bc	115
emh203	0:c1253c12d4bc	116	BYTE * MyBufOut = (BYTE *)Buffer;
emh203	0:c1253c12d4bc	117
emh203	0:c1253c12d4bc	118	for(i=0;i<SectorCount;i++)
emh203	0:c1253c12d4bc	119	{
emh203	0:c1253c12d4bc	120	// set write address for single block (CMD24)
emh203	0:c1253c12d4bc	121	if(_cmd(24, (SectorNumber + i) * 512 ) != 0) {
emh203	0:c1253c12d4bc	122	return RES_ERROR;
emh203	0:c1253c12d4bc	123	}
emh203	0:c1253c12d4bc	124
emh203	0:c1253c12d4bc	125	// send the data block
emh203	0:c1253c12d4bc	126	_write(MyBufOut, 512);
emh203	0:c1253c12d4bc	127
emh203	0:c1253c12d4bc	128	MyBufOut+=512;
emh203	0:c1253c12d4bc	129	}
emh203	0:c1253c12d4bc	130	return RES_OK;
emh203	0:c1253c12d4bc	131	}
emh203	0:c1253c12d4bc	132
emh203	0:c1253c12d4bc	133	DRESULT disk_read(BYTE Drive, BYTE * Buffer,DWORD SectorNumber, BYTE SectorCount)
emh203	0:c1253c12d4bc	134	{
emh203	0:c1253c12d4bc	135	BYTE i;
emh203	0:c1253c12d4bc	136	for(i=0;i<SectorCount;i++)
emh203	0:c1253c12d4bc	137	{
emh203	0:c1253c12d4bc	138	// set read address for single block (CMD17)
emh203	0:c1253c12d4bc	139	if(_cmd(17, (SectorNumber+i) * 512) != 0)
emh203	0:c1253c12d4bc	140	{
emh203	0:c1253c12d4bc	141	return RES_ERROR;
emh203	0:c1253c12d4bc	142	}
emh203	0:c1253c12d4bc	143	// receive the data
emh203	0:c1253c12d4bc	144	_read(Buffer, 512);
emh203	0:c1253c12d4bc	145
emh203	0:c1253c12d4bc	146	Buffer+=512;
emh203	0:c1253c12d4bc	147	}
emh203	0:c1253c12d4bc	148	return RES_OK;
emh203	0:c1253c12d4bc	149	}
emh203	0:c1253c12d4bc	150
emh203	0:c1253c12d4bc	151
emh203	0:c1253c12d4bc	152	DWORD get_fattime(void)
emh203	0:c1253c12d4bc	153	{
emh203	0:c1253c12d4bc	154	time_t CurrentTimeStamp;
emh203	0:c1253c12d4bc	155	tm *CurrentLocalTime;
emh203	0:c1253c12d4bc	156	DWORD FATFSTimeCode;
emh203	0:c1253c12d4bc	157
emh203	0:c1253c12d4bc	158	CurrentTimeStamp = time(NULL);
emh203	0:c1253c12d4bc	159	CurrentLocalTime = localtime(&CurrentTimeStamp);
emh203	0:c1253c12d4bc	160
emh203	0:c1253c12d4bc	161	//Map the tm struct time into the FatFs time code
emh203	0:c1253c12d4bc	162	FATFSTimeCode = ((CurrentLocalTime->tm_year-80)<<25) \|
emh203	0:c1253c12d4bc	163	((CurrentLocalTime->tm_mon+1)<<21) \|
emh203	0:c1253c12d4bc	164	((CurrentLocalTime->tm_mday)<<16) \|
emh203	0:c1253c12d4bc	165	((CurrentLocalTime->tm_hour)<<11) \|
emh203	0:c1253c12d4bc	166	((CurrentLocalTime->tm_min)<<5) \|
emh203	0:c1253c12d4bc	167	((CurrentLocalTime->tm_sec));
emh203	0:c1253c12d4bc	168
emh203	0:c1253c12d4bc	169	return FATFSTimeCode;
emh203	0:c1253c12d4bc	170	}
emh203	0:c1253c12d4bc	171
emh203	0:c1253c12d4bc	172	DSTATUS disk_status(BYTE Drive)
emh203	0:c1253c12d4bc	173	{
emh203	0:c1253c12d4bc	174	return 0;
emh203	0:c1253c12d4bc	175	}
emh203	0:c1253c12d4bc	176
emh203	0:c1253c12d4bc	177	//**************************************************************************************
emh203	0:c1253c12d4bc	178	// Low Level Sector Access Functions (Castrated versions of Simon Fords C++ MBED class
emh203	0:c1253c12d4bc	179	//**************************************************************************************
emh203	0:c1253c12d4bc	180
emh203	0:c1253c12d4bc	181	int _cmd(int cmd, int arg) {
emh203	0:c1253c12d4bc	182	_cs = 0;
emh203	0:c1253c12d4bc	183
emh203	0:c1253c12d4bc	184	// send a command
emh203	0:c1253c12d4bc	185	_spi.write(0x40 \| cmd);
emh203	0:c1253c12d4bc	186	_spi.write(arg >> 24);
emh203	0:c1253c12d4bc	187	_spi.write(arg >> 16);
emh203	0:c1253c12d4bc	188	_spi.write(arg >> 8);
emh203	0:c1253c12d4bc	189	_spi.write(arg >> 0);
emh203	0:c1253c12d4bc	190	_spi.write(0x95);
emh203	0:c1253c12d4bc	191
emh203	0:c1253c12d4bc	192	// wait for the repsonse (response[7] == 0)
emh203	0:c1253c12d4bc	193	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
emh203	0:c1253c12d4bc	194	int response = _spi.write(0xFF);
emh203	0:c1253c12d4bc	195	if(!(response & 0x80)) {
emh203	0:c1253c12d4bc	196	_cs = 1;
emh203	0:c1253c12d4bc	197	return response;
emh203	0:c1253c12d4bc	198	}
emh203	0:c1253c12d4bc	199	}
emh203	0:c1253c12d4bc	200	_cs = 1;
emh203	0:c1253c12d4bc	201	return -1; // timeout
emh203	0:c1253c12d4bc	202	}
emh203	0:c1253c12d4bc	203
emh203	0:c1253c12d4bc	204	int _read(BYTE *buffer, int length) {
emh203	0:c1253c12d4bc	205	_cs = 0;
emh203	0:c1253c12d4bc	206
emh203	0:c1253c12d4bc	207	// read until start byte (0xFF)
emh203	0:c1253c12d4bc	208	while(_spi.write(0xFF) != 0xFE);
emh203	0:c1253c12d4bc	209
emh203	0:c1253c12d4bc	210	// read data
emh203	0:c1253c12d4bc	211	for(int i=0; i<length; i++) {
emh203	0:c1253c12d4bc	212	buffer[i] = _spi.write(0xFF);
emh203	0:c1253c12d4bc	213	}
emh203	0:c1253c12d4bc	214	_spi.write(0xFF); // checksum
emh203	0:c1253c12d4bc	215	_spi.write(0xFF);
emh203	0:c1253c12d4bc	216
emh203	0:c1253c12d4bc	217	_cs = 1;
emh203	0:c1253c12d4bc	218	return 0;
emh203	0:c1253c12d4bc	219	}
emh203	0:c1253c12d4bc	220
emh203	0:c1253c12d4bc	221	int _write(BYTE *buffer, int length) {
emh203	0:c1253c12d4bc	222	_cs = 0;
emh203	0:c1253c12d4bc	223
emh203	0:c1253c12d4bc	224	// indicate start of block
emh203	0:c1253c12d4bc	225	_spi.write(0xFE);
emh203	0:c1253c12d4bc	226
emh203	0:c1253c12d4bc	227	// write the data
emh203	0:c1253c12d4bc	228	for(int i=0; i<length; i++) {
emh203	0:c1253c12d4bc	229	_spi.write(buffer[i]);
emh203	0:c1253c12d4bc	230	}
emh203	0:c1253c12d4bc	231
emh203	0:c1253c12d4bc	232	// write the checksum
emh203	0:c1253c12d4bc	233	_spi.write(0xFF);
emh203	0:c1253c12d4bc	234	_spi.write(0xFF);
emh203	0:c1253c12d4bc	235
emh203	0:c1253c12d4bc	236	// check the repsonse token
emh203	0:c1253c12d4bc	237	if((_spi.write(0xFF) & 0x1F) != 0x05) {
emh203	0:c1253c12d4bc	238	_cs = 1;
emh203	0:c1253c12d4bc	239	return 1;
emh203	0:c1253c12d4bc	240	}
emh203	0:c1253c12d4bc	241
emh203	0:c1253c12d4bc	242	// wait for write to finish
emh203	0:c1253c12d4bc	243	while(_spi.write(0xFF) == 0);
emh203	0:c1253c12d4bc	244
emh203	0:c1253c12d4bc	245	_cs = 1;
emh203	0:c1253c12d4bc	246	return 0;
emh203	0:c1253c12d4bc	247	}
emh203	0:c1253c12d4bc	248
emh203	0:c1253c12d4bc	249	int ext_bits(BYTE *data, int msb, int lsb) {
emh203	0:c1253c12d4bc	250	int bits = 0;
emh203	0:c1253c12d4bc	251	int size = 1 + msb - lsb;
emh203	0:c1253c12d4bc	252	for(int i=0; i<size; i++) {
emh203	0:c1253c12d4bc	253	int position = lsb + i;
emh203	0:c1253c12d4bc	254	int byte = 15 - (position >> 3);
emh203	0:c1253c12d4bc	255	int bit = position & 0x7;
emh203	0:c1253c12d4bc	256	int value = (data[byte] >> bit) & 1;
emh203	0:c1253c12d4bc	257	bits \|= value << i;
emh203	0:c1253c12d4bc	258	}
emh203	0:c1253c12d4bc	259	return bits;
emh203	0:c1253c12d4bc	260	}
emh203	0:c1253c12d4bc	261
emh203	0:c1253c12d4bc	262	int _sd_sectors() {
emh203	0:c1253c12d4bc	263
emh203	0:c1253c12d4bc	264	// CMD9, Response R2 (R1 byte + 16-byte block read)
emh203	0:c1253c12d4bc	265	if(_cmd(9, 0) != 0) {
emh203	0:c1253c12d4bc	266	fprintf(stderr, "Didn't get a response from the disk\n");
emh203	0:c1253c12d4bc	267	return 0;
emh203	0:c1253c12d4bc	268	}
emh203	0:c1253c12d4bc	269
emh203	0:c1253c12d4bc	270	BYTE csd[16];
emh203	0:c1253c12d4bc	271	if(_read(csd, 16) != 0) {
emh203	0:c1253c12d4bc	272	fprintf(stderr, "Couldn't read csd response from disk\n");
emh203	0:c1253c12d4bc	273	return 0;
emh203	0:c1253c12d4bc	274	}
emh203	0:c1253c12d4bc	275
emh203	0:c1253c12d4bc	276	// csd_structure : csd[127:126]
emh203	0:c1253c12d4bc	277	// c_size : csd[73:62]
emh203	0:c1253c12d4bc	278	// c_size_mult : csd[49:47]
emh203	0:c1253c12d4bc	279	// read_bl_len : csd[83:80]
emh203	0:c1253c12d4bc	280
emh203	0:c1253c12d4bc	281	int csd_structure = ext_bits(csd, 127, 126);
emh203	0:c1253c12d4bc	282	int c_size = ext_bits(csd, 73, 62);
emh203	0:c1253c12d4bc	283	int c_size_mult = ext_bits(csd, 49, 47);
emh203	0:c1253c12d4bc	284	int read_bl_len = ext_bits(csd, 83, 80);
emh203	0:c1253c12d4bc	285
emh203	0:c1253c12d4bc	286	if(csd_structure != 0) {
emh203	0:c1253c12d4bc	287	fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures");
emh203	0:c1253c12d4bc	288	return 0;
emh203	0:c1253c12d4bc	289	}
emh203	0:c1253c12d4bc	290
emh203	0:c1253c12d4bc	291	int blocks = (c_size + 1) * (1 << (c_size_mult + 2));
emh203	0:c1253c12d4bc	292	int block_size = 1 << read_bl_len;
emh203	0:c1253c12d4bc	293
emh203	0:c1253c12d4bc	294	if(block_size != 512) {
emh203	0:c1253c12d4bc	295	fprintf(stderr, "This disk tastes funny! I only like 512 byte blocks (%d)\r\n",block_size);
emh203	0:c1253c12d4bc	296	return 0;
emh203	0:c1253c12d4bc	297	}
emh203	0:c1253c12d4bc	298
emh203	0:c1253c12d4bc	299	return blocks;
emh203	0:c1253c12d4bc	300	}

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Type:	Library
Created:	21 Feb 2010
Imports:	54
Forks:	1
Commits:	2
Dependents:	0
Dependencies:	0
Followers:	9

chan_fs/diskio.c@0:c1253c12d4bc, 2010-02-21 (annotated)

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