4 * Copyright 2003, 2004, 2005 Develer S.r.l. (http://www.develer.com/)
5 * This file is part of DevLib - See README.devlib for information.
8 * \brief Driver for the 24xx16 and 24xx256 I2C EEPROMS (implementation)
10 * \note This implementation is AVR specific.
13 * \author Stefano Fedrigo <aleph@develer.com>
14 * \author Bernardo Innocenti <bernie@develer.com>
19 *#* Revision 1.19 2006/03/20 17:49:50 bernie
20 *#* Make the TWI driver more generic to work with devices other than EEPROMS.
22 *#* Revision 1.18 2005/11/27 23:33:40 bernie
23 *#* Use appconfig.h instead of cfg/config.h.
25 *#* Revision 1.17 2005/04/11 19:10:27 bernie
26 *#* Include top-level headers from cfg/ subdir.
28 *#* Revision 1.16 2005/03/01 23:25:09 bernie
31 *#* Revision 1.11 2004/10/26 08:35:31 bernie
32 *#* Reset watchdog for long operations.
34 *#* Revision 1.10 2004/09/20 03:31:22 bernie
37 *#* Revision 1.9 2004/09/14 21:03:46 bernie
38 *#* Use debug.h instead of kdebug.h.
43 #include <cfg/debug.h>
44 #include <appconfig.h> // CONFIG_EEPROM_VERIFY
45 #include <cfg/macros.h> // MIN()
48 #include <mware/byteorder.h> // cpu_to_be16()
50 #include <string.h> // memset()
53 // Configuration sanity checks
54 #if !defined(CONFIG_EEPROM_VERIFY) || (CONFIG_EEPROM_VERIFY != 0 && CONFIG_EEPROM_VERIFY != 1)
55 #error CONFIG_EEPROM_VERIFY must be defined to either 0 or 1
61 #define EEPROM_ID 0xA0
64 * This macros form the correct slave address for EEPROMs
66 #define EEPROM_ADDR(x) (EEPROM_ID | (((uint8_t)(x)) << 1))
72 * Copy \c count bytes from buffer \c buf to
73 * eeprom at address \c addr.
75 static bool eeprom_writeRaw(e2addr_t addr, const void *buf, size_t count)
78 ASSERT(addr + count <= EEPROM_SIZE);
80 while (count && result)
83 * Split write in multiple sequential mode operations that
84 * don't cross page boundaries.
87 MIN(count, (size_t)(EEPROM_BLKSIZE - (addr & (EEPROM_BLKSIZE - 1))));
89 #if CONFIG_EEPROM_TYPE == EEPROM_24XX16
91 * The 24LC16 uses the slave address as a 3-bit
94 uint8_t blk_addr = (uint8_t)((addr >> 8) & 0x07);
95 uint8_t blk_offs = (uint8_t)addr;
98 twi_start_w(EEPROM_ADDR(blk_addr))
99 && twi_send(&blk_offs, sizeof blk_offs)
100 && twi_send(buf, size);
102 #elif CONFIG_EEPROM_TYPE == EEPROM_24XX256
104 // 24LC256 wants big-endian addresses
105 uint16_t addr_be = cpu_to_be16(addr);
108 twi_start_w(EEPROM_ID)
109 && twi_send((uint8_t *)&addr_be, sizeof addr_be)
110 && twi_send(buf, size);
113 #error Unknown device type
119 //kprintf("addr=%d, count=%d, size=%d, *#?=%d\n",
120 // addr, count, size,
121 // (EEPROM_BLKSIZE - (addr & (EEPROM_BLKSIZE - 1)))
124 /* Update count and addr for next operation */
127 buf = ((const char *)buf) + size;
131 TRACEMSG("Write error!");
136 #if CONFIG_EEPROM_VERIFY
138 * Check that the contents of an EEPROM range
139 * match with a provided data buffer.
141 * \return true on success.
143 static bool eeprom_verify(e2addr_t addr, const void *buf, size_t count)
145 uint8_t verify_buf[16];
148 while (count && result)
150 /* Split read in smaller pieces */
151 size_t size = MIN(count, sizeof verify_buf);
153 /* Read back buffer */
154 if (eeprom_read(addr, verify_buf, size))
156 if (memcmp(buf, verify_buf, size) != 0)
158 TRACEMSG("Data mismatch!");
164 TRACEMSG("Read error!");
168 /* Update count and addr for next operation */
171 buf = ((const char *)buf) + size;
176 #endif /* CONFIG_EEPROM_VERIFY */
179 bool eeprom_write(e2addr_t addr, const void *buf, size_t count)
181 #if CONFIG_EEPROM_VERIFY
185 if (eeprom_writeRaw(addr, buf, count)
186 && eeprom_verify(addr, buf, count))
191 #else /* !CONFIG_EEPROM_VERIFY */
192 return eeprom_writeRaw(addr, buf, count);
193 #endif /* !CONFIG_EEPROM_VERIFY */
198 * Copy \c count bytes at address \c addr
199 * from eeprom to RAM to buffer \c buf.
201 * \return true on success.
203 bool eeprom_read(e2addr_t addr, void *buf, size_t count)
205 ASSERT(addr + count <= EEPROM_SIZE);
207 #if CONFIG_EEPROM_TYPE == EEPROM_24XX16
209 * The 24LC16 uses the slave address as a 3-bit
212 uint8_t blk_addr = (uint8_t)((addr >> 8) & 0x07);
213 uint8_t blk_offs = (uint8_t)addr;
216 twi_start_w(EEPROM_ADDR(blk_addr))
217 && twi_send(&blk_offs, sizeof blk_offs)
218 && twi_start_r(EEPROM_ADDR(blk_addr))
219 && twi_recv(buf, count);
221 #elif CONFIG_EEPROM_TYPE == EEPROM_24XX256
223 // 24LC256 wants big-endian addresses
224 addr = cpu_to_be16(addr);
227 twi_start_w(EEPROM_ID)
228 && twi_send((uint8_t *)&addr, sizeof(addr))
229 && twi_start_r(EEPROM_ID)
230 && twi_recv(buf, count);
232 #error Unknown device type
238 TRACEMSG("Read error!");
244 * Write a single character \a c at address \a addr.
246 bool eeprom_write_char(e2addr_t addr, char c)
248 return eeprom_write(addr, &c, 1);
253 * Read a single character at address \a addr.
255 * \return the requested character or -1 in case of failure.
257 int eeprom_read_char(e2addr_t addr)
261 if (eeprom_read(addr, &c, 1))
269 * Erase specified part of eeprom, writing 0xFF.
271 * \param addr starting address
272 * \param count length of block to erase
274 void eeprom_erase(e2addr_t addr, size_t count)
276 uint8_t buf[EEPROM_BLKSIZE];
277 memset(buf, 0xFF, sizeof buf);
279 // Clear all but struct hw_info at start of eeprom
282 // Long operation, reset watchdog
285 size_t size = MIN(count, sizeof buf);
286 eeprom_write(addr, buf, size);
294 * Initialize TWI module.
296 void eeprom_init(void)
306 void eeprom_test(void)
308 static const char magic[14] = "Humpty Dumpty";
309 char buf[sizeof magic];
312 // Write something to EEPROM using unaligned sequential writes
313 for (i = 0; i < 42; ++i)
316 eeprom_write(i * sizeof magic, magic, sizeof magic);
319 // Read back with single-byte reads
320 for (i = 0; i < 42 * sizeof magic; ++i)
323 eeprom_read(i, buf, 1);
324 kprintf("EEPROM byte read: %c (%d)\n", buf[0], buf[0]);
325 ASSERT(buf[0] == magic[i % sizeof magic]);
328 // Read back again using sequential reads
329 for (i = 0; i < 42; ++i)
332 memset(buf, 0, sizeof buf);
333 eeprom_read(i * sizeof magic, buf, sizeof magic);
334 kprintf("EEPROM seq read @ 0x%x: '%s'\n", i * sizeof magic, buf);
335 ASSERT(memcmp(buf, magic, sizeof magic) == 0);