RawLoader - Packed 12bit Raw image file load to display to No…

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Yuji Sakai / Mbed 2 deprecated RawLoader

Packed 12bit Raw image file load to display to Nokia LCD. Add function "blit12" to Nokia LCD for native 12bit color buffer.

Dependencies: mbed

SDFileSystem.cpp@4:f746ea56e891, 2011-02-10 (annotated)

Committer:: sakai
Date:: Thu Feb 10 14:44:49 2011 +0000
Revision:: 4:f746ea56e891
Parent:: 0:b9050fc6f305

Who changed what in which revision?

User	Revision	Line number	New contents of line
sakai	0:b9050fc6f305	1	/* mbed SDFileSystem Library, for providing file access to SD cards
sakai	0:b9050fc6f305	2	* Copyright (c) 2008-2010, sford
sakai	0:b9050fc6f305	3	*
sakai	0:b9050fc6f305	4	* Permission is hereby granted, free of charge, to any person obtaining a copy
sakai	0:b9050fc6f305	5	* of this software and associated documentation files (the "Software"), to deal
sakai	0:b9050fc6f305	6	* in the Software without restriction, including without limitation the rights
sakai	0:b9050fc6f305	7	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
sakai	0:b9050fc6f305	8	* copies of the Software, and to permit persons to whom the Software is
sakai	0:b9050fc6f305	9	* furnished to do so, subject to the following conditions:
sakai	0:b9050fc6f305	10	*
sakai	0:b9050fc6f305	11	* The above copyright notice and this permission notice shall be included in
sakai	0:b9050fc6f305	12	* all copies or substantial portions of the Software.
sakai	0:b9050fc6f305	13	*
sakai	0:b9050fc6f305	14	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
sakai	0:b9050fc6f305	15	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
sakai	0:b9050fc6f305	16	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
sakai	0:b9050fc6f305	17	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
sakai	0:b9050fc6f305	18	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
sakai	0:b9050fc6f305	19	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
sakai	0:b9050fc6f305	20	* THE SOFTWARE.
sakai	0:b9050fc6f305	21	*/
sakai	0:b9050fc6f305	22
sakai	0:b9050fc6f305	23	/* Introduction
sakai	0:b9050fc6f305	24	* ------------
sakai	0:b9050fc6f305	25	* SD and MMC cards support a number of interfaces, but common to them all
sakai	0:b9050fc6f305	26	* is one based on SPI. This is the one I'm implmenting because it means
sakai	0:b9050fc6f305	27	* it is much more portable even though not so performant, and we already
sakai	0:b9050fc6f305	28	* have the mbed SPI Interface!
sakai	0:b9050fc6f305	29	*
sakai	0:b9050fc6f305	30	* The main reference I'm using is Chapter 7, "SPI Mode" of:
sakai	0:b9050fc6f305	31	* http://www.sdcard.org/developers/tech/sdcard/pls/Simplified_Physical_Layer_Spec.pdf
sakai	0:b9050fc6f305	32	*
sakai	0:b9050fc6f305	33	* SPI Startup
sakai	0:b9050fc6f305	34	* -----------
sakai	0:b9050fc6f305	35	* The SD card powers up in SD mode. The SPI interface mode is selected by
sakai	0:b9050fc6f305	36	* asserting CS low and sending the reset command (CMD0). The card will
sakai	0:b9050fc6f305	37	* respond with a (R1) response.
sakai	0:b9050fc6f305	38	*
sakai	0:b9050fc6f305	39	* CMD8 is optionally sent to determine the voltage range supported, and
sakai	0:b9050fc6f305	40	* indirectly determine whether it is a version 1.x SD/non-SD card or
sakai	0:b9050fc6f305	41	* version 2.x. I'll just ignore this for now.
sakai	0:b9050fc6f305	42	*
sakai	0:b9050fc6f305	43	* ACMD41 is repeatedly issued to initialise the card, until "in idle"
sakai	0:b9050fc6f305	44	* (bit 0) of the R1 response goes to '0', indicating it is initialised.
sakai	0:b9050fc6f305	45	*
sakai	0:b9050fc6f305	46	* You should also indicate whether the host supports High Capicity cards,
sakai	0:b9050fc6f305	47	* and check whether the card is high capacity - i'll also ignore this
sakai	0:b9050fc6f305	48	*
sakai	0:b9050fc6f305	49	* SPI Protocol
sakai	0:b9050fc6f305	50	* ------------
sakai	0:b9050fc6f305	51	* The SD SPI protocol is based on transactions made up of 8-bit words, with
sakai	0:b9050fc6f305	52	* the host starting every bus transaction by asserting the CS signal low. The
sakai	0:b9050fc6f305	53	* card always responds to commands, data blocks and errors.
sakai	0:b9050fc6f305	54	*
sakai	0:b9050fc6f305	55	* The protocol supports a CRC, but by default it is off (except for the
sakai	0:b9050fc6f305	56	* first reset CMD0, where the CRC can just be pre-calculated, and CMD8)
sakai	0:b9050fc6f305	57	* I'll leave the CRC off I think!
sakai	0:b9050fc6f305	58	*
sakai	0:b9050fc6f305	59	* Standard capacity cards have variable data block sizes, whereas High
sakai	0:b9050fc6f305	60	* Capacity cards fix the size of data block to 512 bytes. I'll therefore
sakai	0:b9050fc6f305	61	* just always use the Standard Capacity cards with a block size of 512 bytes.
sakai	0:b9050fc6f305	62	* This is set with CMD16.
sakai	0:b9050fc6f305	63	*
sakai	0:b9050fc6f305	64	* You can read and write single blocks (CMD17, CMD25) or multiple blocks
sakai	0:b9050fc6f305	65	* (CMD18, CMD25). For simplicity, I'll just use single block accesses. When
sakai	0:b9050fc6f305	66	* the card gets a read command, it responds with a response token, and then
sakai	0:b9050fc6f305	67	* a data token or an error.
sakai	0:b9050fc6f305	68	*
sakai	0:b9050fc6f305	69	* SPI Command Format
sakai	0:b9050fc6f305	70	* ------------------
sakai	0:b9050fc6f305	71	* Commands are 6-bytes long, containing the command, 32-bit argument, and CRC.
sakai	0:b9050fc6f305	72	*
sakai	0:b9050fc6f305	73	* +---------------+------------+------------+-----------+----------+--------------+
sakai	0:b9050fc6f305	74	* \| 01 \| cmd[5:0] \| arg[31:24] \| arg[23:16] \| arg[15:8] \| arg[7:0] \| crc[6:0] \| 1 \|
sakai	0:b9050fc6f305	75	* +---------------+------------+------------+-----------+----------+--------------+
sakai	0:b9050fc6f305	76	*
sakai	0:b9050fc6f305	77	* As I'm not using CRC, I can fix that byte to what is needed for CMD0 (0x95)
sakai	0:b9050fc6f305	78	*
sakai	0:b9050fc6f305	79	* All Application Specific commands shall be preceded with APP_CMD (CMD55).
sakai	0:b9050fc6f305	80	*
sakai	0:b9050fc6f305	81	* SPI Response Format
sakai	0:b9050fc6f305	82	* -------------------
sakai	0:b9050fc6f305	83	* The main response format (R1) is a status byte (normally zero). Key flags:
sakai	0:b9050fc6f305	84	* idle - 1 if the card is in an idle state/initialising
sakai	0:b9050fc6f305	85	* cmd - 1 if an illegal command code was detected
sakai	0:b9050fc6f305	86	*
sakai	0:b9050fc6f305	87	* +-------------------------------------------------+
sakai	0:b9050fc6f305	88	* R1 \| 0 \| arg \| addr \| seq \| crc \| cmd \| erase \| idle \|
sakai	0:b9050fc6f305	89	* +-------------------------------------------------+
sakai	0:b9050fc6f305	90	*
sakai	0:b9050fc6f305	91	* R1b is the same, except it is followed by a busy signal (zeros) until
sakai	0:b9050fc6f305	92	* the first non-zero byte when it is ready again.
sakai	0:b9050fc6f305	93	*
sakai	0:b9050fc6f305	94	* Data Response Token
sakai	0:b9050fc6f305	95	* -------------------
sakai	0:b9050fc6f305	96	* Every data block written to the card is acknowledged by a byte
sakai	0:b9050fc6f305	97	* response token
sakai	0:b9050fc6f305	98	*
sakai	0:b9050fc6f305	99	* +----------------------+
sakai	0:b9050fc6f305	100	* \| xxx \| 0 \| status \| 1 \|
sakai	0:b9050fc6f305	101	* +----------------------+
sakai	0:b9050fc6f305	102	* 010 - OK!
sakai	0:b9050fc6f305	103	* 101 - CRC Error
sakai	0:b9050fc6f305	104	* 110 - Write Error
sakai	0:b9050fc6f305	105	*
sakai	0:b9050fc6f305	106	* Single Block Read and Write
sakai	0:b9050fc6f305	107	* ---------------------------
sakai	0:b9050fc6f305	108	*
sakai	0:b9050fc6f305	109	* Block transfers have a byte header, followed by the data, followed
sakai	0:b9050fc6f305	110	* by a 16-bit CRC. In our case, the data will always be 512 bytes.
sakai	0:b9050fc6f305	111	*
sakai	0:b9050fc6f305	112	* +------+---------+---------+- - - -+---------+-----------+----------+
sakai	0:b9050fc6f305	113	* \| 0xFE \| data[0] \| data[1] \| \| data[n] \| crc[15:8] \| crc[7:0] \|
sakai	0:b9050fc6f305	114	* +------+---------+---------+- - - -+---------+-----------+----------+
sakai	0:b9050fc6f305	115	*/
sakai	0:b9050fc6f305	116
sakai	0:b9050fc6f305	117	#include "SDFileSystem.h"
sakai	0:b9050fc6f305	118
sakai	0:b9050fc6f305	119	#define SD_COMMAND_TIMEOUT 5000
sakai	0:b9050fc6f305	120
sakai	0:b9050fc6f305	121	SDFileSystem::SDFileSystem(PinName mosi, PinName miso, PinName sclk, PinName cs, const char* name) :
sakai	0:b9050fc6f305	122	FATFileSystem(name), _spi(mosi, miso, sclk), _cs(cs) {
sakai	0:b9050fc6f305	123	_cs = 1;
sakai	0:b9050fc6f305	124	}
sakai	0:b9050fc6f305	125
sakai	0:b9050fc6f305	126	#define R1_IDLE_STATE (1 << 0)
sakai	0:b9050fc6f305	127	#define R1_ERASE_RESET (1 << 1)
sakai	0:b9050fc6f305	128	#define R1_ILLEGAL_COMMAND (1 << 2)
sakai	0:b9050fc6f305	129	#define R1_COM_CRC_ERROR (1 << 3)
sakai	0:b9050fc6f305	130	#define R1_ERASE_SEQUENCE_ERROR (1 << 4)
sakai	0:b9050fc6f305	131	#define R1_ADDRESS_ERROR (1 << 5)
sakai	0:b9050fc6f305	132	#define R1_PARAMETER_ERROR (1 << 6)
sakai	0:b9050fc6f305	133
sakai	0:b9050fc6f305	134	// Types
sakai	0:b9050fc6f305	135	// - v1.x Standard Capacity
sakai	0:b9050fc6f305	136	// - v2.x Standard Capacity
sakai	0:b9050fc6f305	137	// - v2.x High Capacity
sakai	0:b9050fc6f305	138	// - Not recognised as an SD Card
sakai	0:b9050fc6f305	139
sakai	0:b9050fc6f305	140	#define SDCARD_FAIL 0
sakai	0:b9050fc6f305	141	#define SDCARD_V1 1
sakai	0:b9050fc6f305	142	#define SDCARD_V2 2
sakai	0:b9050fc6f305	143	#define SDCARD_V2HC 3
sakai	0:b9050fc6f305	144
sakai	0:b9050fc6f305	145	int SDFileSystem::initialise_card() {
sakai	0:b9050fc6f305	146	// Set to 100kHz for initialisation, and clock card with cs = 1
sakai	0:b9050fc6f305	147	_spi.frequency(100000);
sakai	0:b9050fc6f305	148	_cs = 1;
sakai	0:b9050fc6f305	149	for(int i=0; i<16; i++) {
sakai	0:b9050fc6f305	150	_spi.write(0xFF);
sakai	0:b9050fc6f305	151	}
sakai	0:b9050fc6f305	152
sakai	0:b9050fc6f305	153	// send CMD0, should return with all zeros except IDLE STATE set (bit 0)
sakai	0:b9050fc6f305	154	if(_cmd(0, 0) != R1_IDLE_STATE) {
sakai	0:b9050fc6f305	155	fprintf(stderr, "No disk, or could not put SD card in to SPI idle state\n");
sakai	0:b9050fc6f305	156	return SDCARD_FAIL;
sakai	0:b9050fc6f305	157	}
sakai	0:b9050fc6f305	158
sakai	0:b9050fc6f305	159	// send CMD8 to determine whther it is ver 2.x
sakai	0:b9050fc6f305	160	int r = _cmd8();
sakai	0:b9050fc6f305	161	if(r == R1_IDLE_STATE) {
sakai	0:b9050fc6f305	162	return initialise_card_v2();
sakai	0:b9050fc6f305	163	} else if(r == (R1_IDLE_STATE \| R1_ILLEGAL_COMMAND)) {
sakai	0:b9050fc6f305	164	return initialise_card_v1();
sakai	0:b9050fc6f305	165	} else {
sakai	0:b9050fc6f305	166	fprintf(stderr, "Not in idle state after sending CMD8 (not an SD card?)\n");
sakai	0:b9050fc6f305	167	return SDCARD_FAIL;
sakai	0:b9050fc6f305	168	}
sakai	0:b9050fc6f305	169	}
sakai	0:b9050fc6f305	170
sakai	0:b9050fc6f305	171	int SDFileSystem::initialise_card_v1() {
sakai	0:b9050fc6f305	172	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
sakai	0:b9050fc6f305	173	_cmd(55, 0);
sakai	0:b9050fc6f305	174	if(_cmd(41, 0) == 0) {
sakai	0:b9050fc6f305	175	return SDCARD_V1;
sakai	0:b9050fc6f305	176	}
sakai	0:b9050fc6f305	177	}
sakai	0:b9050fc6f305	178
sakai	0:b9050fc6f305	179	fprintf(stderr, "Timeout waiting for v1.x card\n");
sakai	0:b9050fc6f305	180	return SDCARD_FAIL;
sakai	0:b9050fc6f305	181	}
sakai	0:b9050fc6f305	182
sakai	0:b9050fc6f305	183	int SDFileSystem::initialise_card_v2() {
sakai	0:b9050fc6f305	184
sakai	0:b9050fc6f305	185	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
sakai	0:b9050fc6f305	186	_cmd(55, 0);
sakai	0:b9050fc6f305	187	if(_cmd(41, 0) == 0) {
sakai	0:b9050fc6f305	188	_cmd58();
sakai	0:b9050fc6f305	189	return SDCARD_V2;
sakai	0:b9050fc6f305	190	}
sakai	0:b9050fc6f305	191	}
sakai	0:b9050fc6f305	192
sakai	0:b9050fc6f305	193	fprintf(stderr, "Timeout waiting for v2.x card\n");
sakai	0:b9050fc6f305	194	return SDCARD_FAIL;
sakai	0:b9050fc6f305	195	}
sakai	0:b9050fc6f305	196
sakai	0:b9050fc6f305	197	int SDFileSystem::disk_initialize() {
sakai	0:b9050fc6f305	198
sakai	0:b9050fc6f305	199	int i = initialise_card();
sakai	0:b9050fc6f305	200	// printf("init card = %d\n", i);
sakai	0:b9050fc6f305	201	// printf("OK\n");
sakai	0:b9050fc6f305	202
sakai	0:b9050fc6f305	203	_sectors = _sd_sectors();
sakai	0:b9050fc6f305	204
sakai	0:b9050fc6f305	205	// Set block length to 512 (CMD16)
sakai	0:b9050fc6f305	206	if(_cmd(16, 512) != 0) {
sakai	0:b9050fc6f305	207	fprintf(stderr, "Set 512-byte block timed out\n");
sakai	0:b9050fc6f305	208	return 1;
sakai	0:b9050fc6f305	209	}
sakai	0:b9050fc6f305	210
sakai	0:b9050fc6f305	211	_spi.frequency(1000000); // Set to 1MHz for data transfer
sakai	0:b9050fc6f305	212	return 0;
sakai	0:b9050fc6f305	213	}
sakai	0:b9050fc6f305	214
sakai	0:b9050fc6f305	215	int SDFileSystem::disk_write(const char *buffer, int block_number) {
sakai	0:b9050fc6f305	216	// set write address for single block (CMD24)
sakai	0:b9050fc6f305	217	if(_cmd(24, block_number * 512) != 0) {
sakai	0:b9050fc6f305	218	return 1;
sakai	0:b9050fc6f305	219	}
sakai	0:b9050fc6f305	220
sakai	0:b9050fc6f305	221	// send the data block
sakai	0:b9050fc6f305	222	_write(buffer, 512);
sakai	0:b9050fc6f305	223	return 0;
sakai	0:b9050fc6f305	224	}
sakai	0:b9050fc6f305	225
sakai	0:b9050fc6f305	226	int SDFileSystem::disk_read(char *buffer, int block_number) {
sakai	0:b9050fc6f305	227	// set read address for single block (CMD17)
sakai	0:b9050fc6f305	228	if(_cmd(17, block_number * 512) != 0) {
sakai	0:b9050fc6f305	229	return 1;
sakai	0:b9050fc6f305	230	}
sakai	0:b9050fc6f305	231
sakai	0:b9050fc6f305	232	// receive the data
sakai	0:b9050fc6f305	233	_read(buffer, 512);
sakai	0:b9050fc6f305	234	return 0;
sakai	0:b9050fc6f305	235	}
sakai	0:b9050fc6f305	236
sakai	0:b9050fc6f305	237	int SDFileSystem::disk_status() { return 0; }
sakai	0:b9050fc6f305	238	int SDFileSystem::disk_sync() { return 0; }
sakai	0:b9050fc6f305	239	int SDFileSystem::disk_sectors() { return _sectors; }
sakai	0:b9050fc6f305	240
sakai	0:b9050fc6f305	241	// PRIVATE FUNCTIONS
sakai	0:b9050fc6f305	242
sakai	0:b9050fc6f305	243	int SDFileSystem::_cmd(int cmd, int arg) {
sakai	0:b9050fc6f305	244	_cs = 0;
sakai	0:b9050fc6f305	245
sakai	0:b9050fc6f305	246	// send a command
sakai	0:b9050fc6f305	247	_spi.write(0x40 \| cmd);
sakai	0:b9050fc6f305	248	_spi.write(arg >> 24);
sakai	0:b9050fc6f305	249	_spi.write(arg >> 16);
sakai	0:b9050fc6f305	250	_spi.write(arg >> 8);
sakai	0:b9050fc6f305	251	_spi.write(arg >> 0);
sakai	0:b9050fc6f305	252	_spi.write(0x95);
sakai	0:b9050fc6f305	253
sakai	0:b9050fc6f305	254	// wait for the repsonse (response[7] == 0)
sakai	0:b9050fc6f305	255	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
sakai	0:b9050fc6f305	256	int response = _spi.write(0xFF);
sakai	0:b9050fc6f305	257	if(!(response & 0x80)) {
sakai	0:b9050fc6f305	258	_cs = 1;
sakai	0:b9050fc6f305	259	_spi.write(0xFF);
sakai	0:b9050fc6f305	260	return response;
sakai	0:b9050fc6f305	261	}
sakai	0:b9050fc6f305	262	}
sakai	0:b9050fc6f305	263	_cs = 1;
sakai	0:b9050fc6f305	264	_spi.write(0xFF);
sakai	0:b9050fc6f305	265	return -1; // timeout
sakai	0:b9050fc6f305	266	}
sakai	0:b9050fc6f305	267	int SDFileSystem::_cmdx(int cmd, int arg) {
sakai	0:b9050fc6f305	268	_cs = 0;
sakai	0:b9050fc6f305	269
sakai	0:b9050fc6f305	270	// send a command
sakai	0:b9050fc6f305	271	_spi.write(0x40 \| cmd);
sakai	0:b9050fc6f305	272	_spi.write(arg >> 24);
sakai	0:b9050fc6f305	273	_spi.write(arg >> 16);
sakai	0:b9050fc6f305	274	_spi.write(arg >> 8);
sakai	0:b9050fc6f305	275	_spi.write(arg >> 0);
sakai	0:b9050fc6f305	276	_spi.write(0x95);
sakai	0:b9050fc6f305	277
sakai	0:b9050fc6f305	278	// wait for the repsonse (response[7] == 0)
sakai	0:b9050fc6f305	279	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
sakai	0:b9050fc6f305	280	int response = _spi.write(0xFF);
sakai	0:b9050fc6f305	281	if(!(response & 0x80)) {
sakai	0:b9050fc6f305	282	return response;
sakai	0:b9050fc6f305	283	}
sakai	0:b9050fc6f305	284	}
sakai	0:b9050fc6f305	285	_cs = 1;
sakai	0:b9050fc6f305	286	_spi.write(0xFF);
sakai	0:b9050fc6f305	287	return -1; // timeout
sakai	0:b9050fc6f305	288	}
sakai	0:b9050fc6f305	289
sakai	0:b9050fc6f305	290
sakai	0:b9050fc6f305	291	int SDFileSystem::_cmd58() {
sakai	0:b9050fc6f305	292	_cs = 0;
sakai	0:b9050fc6f305	293	int arg = 0;
sakai	0:b9050fc6f305	294
sakai	0:b9050fc6f305	295	// send a command
sakai	0:b9050fc6f305	296	_spi.write(0x40 \| 58);
sakai	0:b9050fc6f305	297	_spi.write(arg >> 24);
sakai	0:b9050fc6f305	298	_spi.write(arg >> 16);
sakai	0:b9050fc6f305	299	_spi.write(arg >> 8);
sakai	0:b9050fc6f305	300	_spi.write(arg >> 0);
sakai	0:b9050fc6f305	301	_spi.write(0x95);
sakai	0:b9050fc6f305	302
sakai	0:b9050fc6f305	303	// wait for the repsonse (response[7] == 0)
sakai	0:b9050fc6f305	304	for(int i=0; i<SD_COMMAND_TIMEOUT; i++) {
sakai	0:b9050fc6f305	305	int response = _spi.write(0xFF);
sakai	0:b9050fc6f305	306	if(!(response & 0x80)) {
sakai	0:b9050fc6f305	307	int ocr = _spi.write(0xFF) << 24;
sakai	0:b9050fc6f305	308	ocr \|= _spi.write(0xFF) << 16;
sakai	0:b9050fc6f305	309	ocr \|= _spi.write(0xFF) << 8;
sakai	0:b9050fc6f305	310	ocr \|= _spi.write(0xFF) << 0;
sakai	0:b9050fc6f305	311	// printf("OCR = 0x%08X\n", ocr);
sakai	0:b9050fc6f305	312	_cs = 1;
sakai	0:b9050fc6f305	313	_spi.write(0xFF);
sakai	0:b9050fc6f305	314	return response;
sakai	0:b9050fc6f305	315	}
sakai	0:b9050fc6f305	316	}
sakai	0:b9050fc6f305	317	_cs = 1;
sakai	0:b9050fc6f305	318	_spi.write(0xFF);
sakai	0:b9050fc6f305	319	return -1; // timeout
sakai	0:b9050fc6f305	320	}
sakai	0:b9050fc6f305	321
sakai	0:b9050fc6f305	322	int SDFileSystem::_cmd8() {
sakai	0:b9050fc6f305	323	_cs = 0;
sakai	0:b9050fc6f305	324
sakai	0:b9050fc6f305	325	// send a command
sakai	0:b9050fc6f305	326	_spi.write(0x40 \| 8); // CMD8
sakai	0:b9050fc6f305	327	_spi.write(0x00); // reserved
sakai	0:b9050fc6f305	328	_spi.write(0x00); // reserved
sakai	0:b9050fc6f305	329	_spi.write(0x01); // 3.3v
sakai	0:b9050fc6f305	330	_spi.write(0xAA); // check pattern
sakai	0:b9050fc6f305	331	_spi.write(0x87); // crc
sakai	0:b9050fc6f305	332
sakai	0:b9050fc6f305	333	// wait for the repsonse (response[7] == 0)
sakai	0:b9050fc6f305	334	for(int i=0; i<SD_COMMAND_TIMEOUT * 1000; i++) {
sakai	0:b9050fc6f305	335	char response[5];
sakai	0:b9050fc6f305	336	response[0] = _spi.write(0xFF);
sakai	0:b9050fc6f305	337	if(!(response[0] & 0x80)) {
sakai	0:b9050fc6f305	338	for(int j=1; j<5; j++) {
sakai	0:b9050fc6f305	339	response[i] = _spi.write(0xFF);
sakai	0:b9050fc6f305	340	}
sakai	0:b9050fc6f305	341	_cs = 1;
sakai	0:b9050fc6f305	342	_spi.write(0xFF);
sakai	0:b9050fc6f305	343	return response[0];
sakai	0:b9050fc6f305	344	}
sakai	0:b9050fc6f305	345	}
sakai	0:b9050fc6f305	346	_cs = 1;
sakai	0:b9050fc6f305	347	_spi.write(0xFF);
sakai	0:b9050fc6f305	348	return -1; // timeout
sakai	0:b9050fc6f305	349	}
sakai	0:b9050fc6f305	350
sakai	0:b9050fc6f305	351	int SDFileSystem::_read(char *buffer, int length) {
sakai	0:b9050fc6f305	352	_cs = 0;
sakai	0:b9050fc6f305	353
sakai	0:b9050fc6f305	354	// read until start byte (0xFF)
sakai	0:b9050fc6f305	355	while(_spi.write(0xFF) != 0xFE);
sakai	0:b9050fc6f305	356
sakai	0:b9050fc6f305	357	// read data
sakai	0:b9050fc6f305	358	for(int i=0; i<length; i++) {
sakai	0:b9050fc6f305	359	buffer[i] = _spi.write(0xFF);
sakai	0:b9050fc6f305	360	}
sakai	0:b9050fc6f305	361	_spi.write(0xFF); // checksum
sakai	0:b9050fc6f305	362	_spi.write(0xFF);
sakai	0:b9050fc6f305	363
sakai	0:b9050fc6f305	364	_cs = 1;
sakai	0:b9050fc6f305	365	_spi.write(0xFF);
sakai	0:b9050fc6f305	366	return 0;
sakai	0:b9050fc6f305	367	}
sakai	0:b9050fc6f305	368
sakai	0:b9050fc6f305	369	int SDFileSystem::_write(const char *buffer, int length) {
sakai	0:b9050fc6f305	370	_cs = 0;
sakai	0:b9050fc6f305	371
sakai	0:b9050fc6f305	372	// indicate start of block
sakai	0:b9050fc6f305	373	_spi.write(0xFE);
sakai	0:b9050fc6f305	374
sakai	0:b9050fc6f305	375	// write the data
sakai	0:b9050fc6f305	376	for(int i=0; i<length; i++) {
sakai	0:b9050fc6f305	377	_spi.write(buffer[i]);
sakai	0:b9050fc6f305	378	}
sakai	0:b9050fc6f305	379
sakai	0:b9050fc6f305	380	// write the checksum
sakai	0:b9050fc6f305	381	_spi.write(0xFF);
sakai	0:b9050fc6f305	382	_spi.write(0xFF);
sakai	0:b9050fc6f305	383
sakai	0:b9050fc6f305	384	// check the repsonse token
sakai	0:b9050fc6f305	385	if((_spi.write(0xFF) & 0x1F) != 0x05) {
sakai	0:b9050fc6f305	386	_cs = 1;
sakai	0:b9050fc6f305	387	_spi.write(0xFF);
sakai	0:b9050fc6f305	388	return 1;
sakai	0:b9050fc6f305	389	}
sakai	0:b9050fc6f305	390
sakai	0:b9050fc6f305	391	// wait for write to finish
sakai	0:b9050fc6f305	392	while(_spi.write(0xFF) == 0);
sakai	0:b9050fc6f305	393
sakai	0:b9050fc6f305	394	_cs = 1;
sakai	0:b9050fc6f305	395	_spi.write(0xFF);
sakai	0:b9050fc6f305	396	return 0;
sakai	0:b9050fc6f305	397	}
sakai	0:b9050fc6f305	398
sakai	0:b9050fc6f305	399	static int ext_bits(char *data, int msb, int lsb) {
sakai	0:b9050fc6f305	400	int bits = 0;
sakai	0:b9050fc6f305	401	int size = 1 + msb - lsb;
sakai	0:b9050fc6f305	402	for(int i=0; i<size; i++) {
sakai	0:b9050fc6f305	403	int position = lsb + i;
sakai	0:b9050fc6f305	404	int byte = 15 - (position >> 3);
sakai	0:b9050fc6f305	405	int bit = position & 0x7;
sakai	0:b9050fc6f305	406	int value = (data[byte] >> bit) & 1;
sakai	0:b9050fc6f305	407	bits \|= value << i;
sakai	0:b9050fc6f305	408	}
sakai	0:b9050fc6f305	409	return bits;
sakai	0:b9050fc6f305	410	}
sakai	0:b9050fc6f305	411
sakai	0:b9050fc6f305	412	int SDFileSystem::_sd_sectors() {
sakai	0:b9050fc6f305	413
sakai	0:b9050fc6f305	414	// CMD9, Response R2 (R1 byte + 16-byte block read)
sakai	0:b9050fc6f305	415	if(_cmdx(9, 0) != 0) {
sakai	0:b9050fc6f305	416	fprintf(stderr, "Didn't get a response from the disk\n");
sakai	0:b9050fc6f305	417	return 0;
sakai	0:b9050fc6f305	418	}
sakai	0:b9050fc6f305	419
sakai	0:b9050fc6f305	420	char csd[16];
sakai	0:b9050fc6f305	421	if(_read(csd, 16) != 0) {
sakai	0:b9050fc6f305	422	fprintf(stderr, "Couldn't read csd response from disk\n");
sakai	0:b9050fc6f305	423	return 0;
sakai	0:b9050fc6f305	424	}
sakai	0:b9050fc6f305	425
sakai	0:b9050fc6f305	426	// csd_structure : csd[127:126]
sakai	0:b9050fc6f305	427	// c_size : csd[73:62]
sakai	0:b9050fc6f305	428	// c_size_mult : csd[49:47]
sakai	0:b9050fc6f305	429	// read_bl_len : csd[83:80] - the maximum read block length
sakai	0:b9050fc6f305	430
sakai	0:b9050fc6f305	431	int csd_structure = ext_bits(csd, 127, 126);
sakai	0:b9050fc6f305	432	int c_size = ext_bits(csd, 73, 62);
sakai	0:b9050fc6f305	433	int c_size_mult = ext_bits(csd, 49, 47);
sakai	0:b9050fc6f305	434	int read_bl_len = ext_bits(csd, 83, 80);
sakai	0:b9050fc6f305	435
sakai	0:b9050fc6f305	436	// printf("CSD_STRUCT = %d\n", csd_structure);
sakai	0:b9050fc6f305	437
sakai	0:b9050fc6f305	438	if(csd_structure != 0) {
sakai	0:b9050fc6f305	439	fprintf(stderr, "This disk tastes funny! I only know about type 0 CSD structures\n");
sakai	0:b9050fc6f305	440	return 0;
sakai	0:b9050fc6f305	441	}
sakai	0:b9050fc6f305	442
sakai	0:b9050fc6f305	443	// memory capacity = BLOCKNR * BLOCK_LEN
sakai	0:b9050fc6f305	444	// where
sakai	0:b9050fc6f305	445	// BLOCKNR = (C_SIZE+1) * MULT
sakai	0:b9050fc6f305	446	// MULT = 2^(C_SIZE_MULT+2) (C_SIZE_MULT < 8)
sakai	0:b9050fc6f305	447	// BLOCK_LEN = 2^READ_BL_LEN, (READ_BL_LEN < 12)
sakai	0:b9050fc6f305	448
sakai	0:b9050fc6f305	449	int block_len = 1 << read_bl_len;
sakai	0:b9050fc6f305	450	int mult = 1 << (c_size_mult + 2);
sakai	0:b9050fc6f305	451	int blocknr = (c_size + 1) * mult;
sakai	0:b9050fc6f305	452	int capacity = blocknr * block_len;
sakai	0:b9050fc6f305	453
sakai	0:b9050fc6f305	454	int blocks = capacity / 512;
sakai	0:b9050fc6f305	455
sakai	0:b9050fc6f305	456	return blocks;
sakai	0:b9050fc6f305	457	}

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Type:	Program
Mbed OS support:	Mbed 2 deprecated
Created:	09 Feb 2011
Imports:	9
Forks:	0
Commits:	5
Dependents:	0
Dependencies:	1
Followers:	1

SDFileSystem.cpp@4:f746ea56e891, 2011-02-10 (annotated)

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