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 1.18 2005/11/27 23:33:40 bernie
20 *#* Use appconfig.h instead of cfg/config.h.
22 *#* Revision 1.17 2005/04/11 19:10:27 bernie
23 *#* Include top-level headers from cfg/ subdir.
25 *#* Revision 1.16 2005/03/01 23:25:09 bernie
28 *#* Revision 1.11 2004/10/26 08:35:31 bernie
29 *#* Reset watchdog for long operations.
31 *#* Revision 1.10 2004/09/20 03:31:22 bernie
34 *#* Revision 1.9 2004/09/14 21:03:46 bernie
35 *#* Use debug.h instead of kdebug.h.
40 #include <cfg/debug.h>
41 #include <appconfig.h> // CONFIG_EEPROM_VERIFY
42 #include <cfg/macros.h> // MIN()
45 #include <mware/byteorder.h> // cpu_to_be16()
47 #include <string.h> // memset()
50 // Configuration sanity checks
51 #if !defined(CONFIG_EEPROM_VERIFY) || (CONFIG_EEPROM_VERIFY != 0 && CONFIG_EEPROM_VERIFY != 1)
52 #error CONFIG_EEPROM_VERIFY must be defined to either 0 or 1
57 * Copy \c count bytes from buffer \c buf to
58 * eeprom at address \c addr.
60 static bool eeprom_writeRaw(e2addr_t addr, const void *buf, size_t count)
63 ASSERT(addr + count <= EEPROM_SIZE);
65 while (count && result)
68 * Split write in multiple sequential mode operations that
69 * don't cross page boundaries.
72 MIN(count, (size_t)(EEPROM_BLKSIZE - (addr & (EEPROM_BLKSIZE - 1))));
74 #if CONFIG_EEPROM_TYPE == EEPROM_24XX16
76 * The 24LC16 uses the slave address as a 3-bit
79 uint8_t blk_addr = (uint8_t)((addr >> 8) & 0x07);
80 uint8_t blk_offs = (uint8_t)addr;
84 && twi_send(&blk_offs, sizeof blk_offs)
85 && twi_send(buf, size);
87 #elif CONFIG_EEPROM_TYPE == EEPROM_24XX256
89 // 24LC256 wants big-endian addresses
90 uint16_t addr_be = cpu_to_be16(addr);
94 && twi_send((uint8_t *)&addr_be, sizeof addr_be)
95 && twi_send(buf, size);
98 #error Unknown device type
104 //kprintf("addr=%d, count=%d, size=%d, *#?=%d\n",
105 // addr, count, size,
106 // (EEPROM_BLKSIZE - (addr & (EEPROM_BLKSIZE - 1)))
109 /* Update count and addr for next operation */
112 buf = ((const char *)buf) + size;
116 TRACEMSG("Write error!");
121 #if CONFIG_EEPROM_VERIFY
123 * Check that the contents of an EEPROM range
124 * match with a provided data buffer.
126 * \return true on success.
128 static bool eeprom_verify(e2addr_t addr, const void *buf, size_t count)
130 uint8_t verify_buf[16];
133 while (count && result)
135 /* Split read in smaller pieces */
136 size_t size = MIN(count, sizeof verify_buf);
138 /* Read back buffer */
139 if (eeprom_read(addr, verify_buf, size))
141 if (memcmp(buf, verify_buf, size) != 0)
143 TRACEMSG("Data mismatch!");
149 TRACEMSG("Read error!");
153 /* Update count and addr for next operation */
156 buf = ((const char *)buf) + size;
161 #endif /* CONFIG_EEPROM_VERIFY */
164 bool eeprom_write(e2addr_t addr, const void *buf, size_t count)
166 #if CONFIG_EEPROM_VERIFY
170 if (eeprom_writeRaw(addr, buf, count)
171 && eeprom_verify(addr, buf, count))
176 #else /* !CONFIG_EEPROM_VERIFY */
177 return eeprom_writeRaw(addr, buf, count);
178 #endif /* !CONFIG_EEPROM_VERIFY */
183 * Copy \c count bytes at address \c addr
184 * from eeprom to RAM to buffer \c buf.
186 * \return true on success.
188 bool eeprom_read(e2addr_t addr, void *buf, size_t count)
190 ASSERT(addr + count <= EEPROM_SIZE);
192 #if CONFIG_EEPROM_TYPE == EEPROM_24XX16
194 * The 24LC16 uses the slave address as a 3-bit
197 uint8_t blk_addr = (uint8_t)((addr >> 8) & 0x07);
198 uint8_t blk_offs = (uint8_t)addr;
201 twi_start_w(blk_addr)
202 && twi_send(&blk_offs, sizeof blk_offs)
203 && twi_start_r(blk_addr)
204 && twi_recv(buf, count);
206 #elif CONFIG_EEPROM_TYPE == EEPROM_24XX256
208 // 24LC256 wants big-endian addresses
209 addr = cpu_to_be16(addr);
213 && twi_send((uint8_t *)&addr, sizeof(addr))
215 && twi_recv(buf, count);
217 #error Unknown device type
223 TRACEMSG("Read error!");
229 * Write a single character \a c at address \a addr.
231 bool eeprom_write_char(e2addr_t addr, char c)
233 return eeprom_write(addr, &c, 1);
238 * Read a single character at address \a addr.
240 * \return the requested character or -1 in case of failure.
242 int eeprom_read_char(e2addr_t addr)
246 if (eeprom_read(addr, &c, 1))
254 * Erase specified part of eeprom, writing 0xFF.
256 * \param addr starting address
257 * \param count length of block to erase
259 void eeprom_erase(e2addr_t addr, size_t count)
261 uint8_t buf[EEPROM_BLKSIZE];
262 memset(buf, 0xFF, sizeof buf);
264 // Clear all but struct hw_info at start of eeprom
267 // Long operation, reset watchdog
270 size_t size = MIN(count, sizeof buf);
271 eeprom_write(addr, buf, size);
279 * Initialize TWI module.
281 void eeprom_init(void)
291 void eeprom_test(void)
293 static const char magic[14] = "Humpty Dumpty";
294 char buf[sizeof magic];
297 // Write something to EEPROM using unaligned sequential writes
298 for (i = 0; i < 42; ++i)
301 eeprom_write(i * sizeof magic, magic, sizeof magic);
304 // Read back with single-byte reads
305 for (i = 0; i < 42 * sizeof magic; ++i)
308 eeprom_read(i, buf, 1);
309 kprintf("EEPROM byte read: %c (%d)\n", buf[0], buf[0]);
310 ASSERT(buf[0] == magic[i % sizeof magic]);
313 // Read back again using sequential reads
314 for (i = 0; i < 42; ++i)
317 memset(buf, 0, sizeof buf);
318 eeprom_read(i * sizeof magic, buf, sizeof magic);
319 kprintf("EEPROM seq read @ 0x%x: '%s'\n", i * sizeof magic, buf);
320 ASSERT(memcmp(buf, magic, sizeof magic) == 0);