Lee Kai Xuan / mbed-os

mbed-os

Fork of mbed-os by erkin yucel

targets/TARGET_STM/TARGET_STM32L1/i2c_api.c@0:f269e3021894, 2016-10-23 (annotated)

Committer:
elessair
Date:
Sun Oct 23 15:10:02 2016 +0000
Revision:
0:f269e3021894
Initial commit

Who changed what in which revision?

UserRevisionLine numberNew contents of line
elessair 0:f269e3021894 1 /* mbed Microcontroller Library
elessair 0:f269e3021894 2 *******************************************************************************
elessair 0:f269e3021894 3 * Copyright (c) 2014, STMicroelectronics
elessair 0:f269e3021894 4 * All rights reserved.
elessair 0:f269e3021894 5 *
elessair 0:f269e3021894 6 * Redistribution and use in source and binary forms, with or without
elessair 0:f269e3021894 7 * modification, are permitted provided that the following conditions are met:
elessair 0:f269e3021894 8 *
elessair 0:f269e3021894 9 * 1. Redistributions of source code must retain the above copyright notice,
elessair 0:f269e3021894 10 * this list of conditions and the following disclaimer.
elessair 0:f269e3021894 11 * 2. Redistributions in binary form must reproduce the above copyright notice,
elessair 0:f269e3021894 12 * this list of conditions and the following disclaimer in the documentation
elessair 0:f269e3021894 13 * and/or other materials provided with the distribution.
elessair 0:f269e3021894 14 * 3. Neither the name of STMicroelectronics nor the names of its contributors
elessair 0:f269e3021894 15 * may be used to endorse or promote products derived from this software
elessair 0:f269e3021894 16 * without specific prior written permission.
elessair 0:f269e3021894 17 *
elessair 0:f269e3021894 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
elessair 0:f269e3021894 19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
elessair 0:f269e3021894 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
elessair 0:f269e3021894 21 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
elessair 0:f269e3021894 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
elessair 0:f269e3021894 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
elessair 0:f269e3021894 24 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
elessair 0:f269e3021894 25 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
elessair 0:f269e3021894 26 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
elessair 0:f269e3021894 27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
elessair 0:f269e3021894 28 *******************************************************************************
elessair 0:f269e3021894 29 */
elessair 0:f269e3021894 30 #include "mbed_assert.h"
elessair 0:f269e3021894 31 #include "i2c_api.h"
elessair 0:f269e3021894 32
elessair 0:f269e3021894 33 #if DEVICE_I2C
elessair 0:f269e3021894 34
elessair 0:f269e3021894 35 #include "cmsis.h"
elessair 0:f269e3021894 36 #include "pinmap.h"
elessair 0:f269e3021894 37 #include "PeripheralPins.h"
elessair 0:f269e3021894 38
elessair 0:f269e3021894 39 /* Timeout values for flags and events waiting loops. These timeouts are
elessair 0:f269e3021894 40 not based on accurate values, they just guarantee that the application will
elessair 0:f269e3021894 41 not remain stuck if the I2C communication is corrupted. */
elessair 0:f269e3021894 42 #define FLAG_TIMEOUT ((int)0x1000)
elessair 0:f269e3021894 43 #define LONG_TIMEOUT ((int)0x8000)
elessair 0:f269e3021894 44
elessair 0:f269e3021894 45 I2C_HandleTypeDef I2cHandle;
elessair 0:f269e3021894 46
elessair 0:f269e3021894 47 int i2c1_inited = 0;
elessair 0:f269e3021894 48 int i2c2_inited = 0;
elessair 0:f269e3021894 49
elessair 0:f269e3021894 50 void i2c_init(i2c_t *obj, PinName sda, PinName scl)
elessair 0:f269e3021894 51 {
elessair 0:f269e3021894 52 // Determine the I2C to use
elessair 0:f269e3021894 53 I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA);
elessair 0:f269e3021894 54 I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL);
elessair 0:f269e3021894 55
elessair 0:f269e3021894 56 obj->i2c = (I2CName)pinmap_merge(i2c_sda, i2c_scl);
elessair 0:f269e3021894 57 MBED_ASSERT(obj->i2c != (I2CName)NC);
elessair 0:f269e3021894 58
elessair 0:f269e3021894 59 // Enable I2C1 clock and pinout if not done
elessair 0:f269e3021894 60 if ((obj->i2c == I2C_1) && !i2c1_inited) {
elessair 0:f269e3021894 61 i2c1_inited = 1;
elessair 0:f269e3021894 62 __I2C1_CLK_ENABLE();
elessair 0:f269e3021894 63 // Configure I2C pins
elessair 0:f269e3021894 64 pinmap_pinout(sda, PinMap_I2C_SDA);
elessair 0:f269e3021894 65 pinmap_pinout(scl, PinMap_I2C_SCL);
elessair 0:f269e3021894 66 pin_mode(sda, OpenDrain);
elessair 0:f269e3021894 67 pin_mode(scl, OpenDrain);
elessair 0:f269e3021894 68 }
elessair 0:f269e3021894 69 // Enable I2C2 clock and pinout if not done
elessair 0:f269e3021894 70 if ((obj->i2c == I2C_2) && !i2c2_inited) {
elessair 0:f269e3021894 71 i2c2_inited = 1;
elessair 0:f269e3021894 72 __I2C2_CLK_ENABLE();
elessair 0:f269e3021894 73 // Configure I2C pins
elessair 0:f269e3021894 74 pinmap_pinout(sda, PinMap_I2C_SDA);
elessair 0:f269e3021894 75 pinmap_pinout(scl, PinMap_I2C_SCL);
elessair 0:f269e3021894 76 pin_mode(sda, OpenDrain);
elessair 0:f269e3021894 77 pin_mode(scl, OpenDrain);
elessair 0:f269e3021894 78 }
elessair 0:f269e3021894 79
elessair 0:f269e3021894 80 // Reset to clear pending flags if any
elessair 0:f269e3021894 81 i2c_reset(obj);
elessair 0:f269e3021894 82
elessair 0:f269e3021894 83 // I2C configuration
elessair 0:f269e3021894 84 i2c_frequency(obj, 100000); // 100 kHz per default
elessair 0:f269e3021894 85
elessair 0:f269e3021894 86 // I2C master by default
elessair 0:f269e3021894 87 obj->slave = 0;
elessair 0:f269e3021894 88 }
elessair 0:f269e3021894 89
elessair 0:f269e3021894 90 void i2c_frequency(i2c_t *obj, int hz)
elessair 0:f269e3021894 91 {
elessair 0:f269e3021894 92 MBED_ASSERT((hz != 0) && (hz <= 400000));
elessair 0:f269e3021894 93 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 94 int timeout;
elessair 0:f269e3021894 95
elessair 0:f269e3021894 96 // wait before init
elessair 0:f269e3021894 97 timeout = LONG_TIMEOUT;
elessair 0:f269e3021894 98 while ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY)) && (timeout-- != 0));
elessair 0:f269e3021894 99
elessair 0:f269e3021894 100 // I2C configuration
elessair 0:f269e3021894 101 I2cHandle.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
elessair 0:f269e3021894 102 I2cHandle.Init.ClockSpeed = hz;
elessair 0:f269e3021894 103 I2cHandle.Init.DualAddressMode = I2C_DUALADDRESS_DISABLED;
elessair 0:f269e3021894 104 I2cHandle.Init.DutyCycle = I2C_DUTYCYCLE_2;
elessair 0:f269e3021894 105 I2cHandle.Init.GeneralCallMode = I2C_GENERALCALL_DISABLED;
elessair 0:f269e3021894 106 I2cHandle.Init.NoStretchMode = I2C_NOSTRETCH_DISABLED;
elessair 0:f269e3021894 107 I2cHandle.Init.OwnAddress1 = 0;
elessair 0:f269e3021894 108 I2cHandle.Init.OwnAddress2 = 0;
elessair 0:f269e3021894 109 HAL_I2C_Init(&I2cHandle);
elessair 0:f269e3021894 110 if (obj->slave) {
elessair 0:f269e3021894 111 /* Enable Address Acknowledge */
elessair 0:f269e3021894 112 I2cHandle.Instance->CR1 |= I2C_CR1_ACK;
elessair 0:f269e3021894 113 }
elessair 0:f269e3021894 114
elessair 0:f269e3021894 115 }
elessair 0:f269e3021894 116
elessair 0:f269e3021894 117 inline int i2c_start(i2c_t *obj)
elessair 0:f269e3021894 118 {
elessair 0:f269e3021894 119 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 120 int timeout;
elessair 0:f269e3021894 121
elessair 0:f269e3021894 122 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 123
elessair 0:f269e3021894 124 // Clear Acknowledge failure flag
elessair 0:f269e3021894 125 __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_AF);
elessair 0:f269e3021894 126
elessair 0:f269e3021894 127 // Wait the STOP condition has been previously correctly sent
elessair 0:f269e3021894 128 // This timeout can be avoid in some specific cases by simply clearing the STOP bit
elessair 0:f269e3021894 129 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 130 while ((i2c->CR1 & I2C_CR1_STOP) == I2C_CR1_STOP) {
elessair 0:f269e3021894 131 if ((timeout--) == 0) {
elessair 0:f269e3021894 132 return 1;
elessair 0:f269e3021894 133 }
elessair 0:f269e3021894 134 }
elessair 0:f269e3021894 135
elessair 0:f269e3021894 136 // Generate the START condition
elessair 0:f269e3021894 137 i2c->CR1 |= I2C_CR1_START;
elessair 0:f269e3021894 138
elessair 0:f269e3021894 139 // Wait the START condition has been correctly sent
elessair 0:f269e3021894 140 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 141 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_SB) == RESET) {
elessair 0:f269e3021894 142 if ((timeout--) == 0) {
elessair 0:f269e3021894 143 return 1;
elessair 0:f269e3021894 144 }
elessair 0:f269e3021894 145 }
elessair 0:f269e3021894 146
elessair 0:f269e3021894 147 return 0;
elessair 0:f269e3021894 148 }
elessair 0:f269e3021894 149
elessair 0:f269e3021894 150 inline int i2c_stop(i2c_t *obj)
elessair 0:f269e3021894 151 {
elessair 0:f269e3021894 152 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 153
elessair 0:f269e3021894 154 // Generate the STOP condition
elessair 0:f269e3021894 155 i2c->CR1 |= I2C_CR1_STOP;
elessair 0:f269e3021894 156
elessair 0:f269e3021894 157 return 0;
elessair 0:f269e3021894 158 }
elessair 0:f269e3021894 159
elessair 0:f269e3021894 160 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop)
elessair 0:f269e3021894 161 {
elessair 0:f269e3021894 162 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 163 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 164 int timeout;
elessair 0:f269e3021894 165 int count;
elessair 0:f269e3021894 166 int value;
elessair 0:f269e3021894 167
elessair 0:f269e3021894 168 i2c_start(obj);
elessair 0:f269e3021894 169
elessair 0:f269e3021894 170 // Wait until SB flag is set
elessair 0:f269e3021894 171 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 172 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_SB) == RESET) {
elessair 0:f269e3021894 173 timeout--;
elessair 0:f269e3021894 174 if (timeout == 0) {
elessair 0:f269e3021894 175 return -1;
elessair 0:f269e3021894 176 }
elessair 0:f269e3021894 177 }
elessair 0:f269e3021894 178
elessair 0:f269e3021894 179 i2c->DR = I2C_7BIT_ADD_READ(address);
elessair 0:f269e3021894 180
elessair 0:f269e3021894 181
elessair 0:f269e3021894 182 // Wait address is acknowledged
elessair 0:f269e3021894 183 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 184 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_ADDR) == RESET) {
elessair 0:f269e3021894 185 timeout--;
elessair 0:f269e3021894 186 if (timeout == 0) {
elessair 0:f269e3021894 187 return -1;
elessair 0:f269e3021894 188 }
elessair 0:f269e3021894 189 }
elessair 0:f269e3021894 190 __HAL_I2C_CLEAR_ADDRFLAG(&I2cHandle);
elessair 0:f269e3021894 191
elessair 0:f269e3021894 192 // Read all bytes except last one
elessair 0:f269e3021894 193 for (count = 0; count < (length - 1); count++) {
elessair 0:f269e3021894 194 value = i2c_byte_read(obj, 0);
elessair 0:f269e3021894 195 data[count] = (char)value;
elessair 0:f269e3021894 196 }
elessair 0:f269e3021894 197
elessair 0:f269e3021894 198 // If not repeated start, send stop.
elessair 0:f269e3021894 199 // Warning: must be done BEFORE the data is read.
elessair 0:f269e3021894 200 if (stop) {
elessair 0:f269e3021894 201 i2c_stop(obj);
elessair 0:f269e3021894 202 }
elessair 0:f269e3021894 203
elessair 0:f269e3021894 204 // Read the last byte
elessair 0:f269e3021894 205 value = i2c_byte_read(obj, 1);
elessair 0:f269e3021894 206 data[count] = (char)value;
elessair 0:f269e3021894 207
elessair 0:f269e3021894 208 return length;
elessair 0:f269e3021894 209 }
elessair 0:f269e3021894 210
elessair 0:f269e3021894 211 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop)
elessair 0:f269e3021894 212 {
elessair 0:f269e3021894 213 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 214 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 215 int timeout;
elessair 0:f269e3021894 216 int count;
elessair 0:f269e3021894 217
elessair 0:f269e3021894 218 i2c_start(obj);
elessair 0:f269e3021894 219
elessair 0:f269e3021894 220 // Wait until SB flag is set
elessair 0:f269e3021894 221 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 222 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_SB) == RESET) {
elessair 0:f269e3021894 223 timeout--;
elessair 0:f269e3021894 224 if (timeout == 0) {
elessair 0:f269e3021894 225 return -1;
elessair 0:f269e3021894 226 }
elessair 0:f269e3021894 227 }
elessair 0:f269e3021894 228
elessair 0:f269e3021894 229 i2c->DR = I2C_7BIT_ADD_WRITE(address);
elessair 0:f269e3021894 230
elessair 0:f269e3021894 231
elessair 0:f269e3021894 232 // Wait address is acknowledged
elessair 0:f269e3021894 233 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 234 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_ADDR) == RESET) {
elessair 0:f269e3021894 235 timeout--;
elessair 0:f269e3021894 236 if (timeout == 0) {
elessair 0:f269e3021894 237 return -1;
elessair 0:f269e3021894 238 }
elessair 0:f269e3021894 239 }
elessair 0:f269e3021894 240 __HAL_I2C_CLEAR_ADDRFLAG(&I2cHandle);
elessair 0:f269e3021894 241
elessair 0:f269e3021894 242 for (count = 0; count < length; count++) {
elessair 0:f269e3021894 243 if (i2c_byte_write(obj, data[count]) != 1) {
elessair 0:f269e3021894 244 i2c_stop(obj);
elessair 0:f269e3021894 245 return -1;
elessair 0:f269e3021894 246 }
elessair 0:f269e3021894 247 }
elessair 0:f269e3021894 248
elessair 0:f269e3021894 249 // If not repeated start, send stop.
elessair 0:f269e3021894 250 if (stop) {
elessair 0:f269e3021894 251 i2c_stop(obj);
elessair 0:f269e3021894 252 }
elessair 0:f269e3021894 253
elessair 0:f269e3021894 254 return count;
elessair 0:f269e3021894 255 }
elessair 0:f269e3021894 256
elessair 0:f269e3021894 257 int i2c_byte_read(i2c_t *obj, int last)
elessair 0:f269e3021894 258 {
elessair 0:f269e3021894 259 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 260 int timeout;
elessair 0:f269e3021894 261
elessair 0:f269e3021894 262 if (last) {
elessair 0:f269e3021894 263 // Don't acknowledge the last byte
elessair 0:f269e3021894 264 i2c->CR1 &= ~I2C_CR1_ACK;
elessair 0:f269e3021894 265 } else {
elessair 0:f269e3021894 266 // Acknowledge the byte
elessair 0:f269e3021894 267 i2c->CR1 |= I2C_CR1_ACK;
elessair 0:f269e3021894 268 }
elessair 0:f269e3021894 269
elessair 0:f269e3021894 270 // Wait until the byte is received
elessair 0:f269e3021894 271 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 272 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_RXNE) == RESET) {
elessair 0:f269e3021894 273 if ((timeout--) == 0) {
elessair 0:f269e3021894 274 return -1;
elessair 0:f269e3021894 275 }
elessair 0:f269e3021894 276 }
elessair 0:f269e3021894 277
elessair 0:f269e3021894 278 return (int)i2c->DR;
elessair 0:f269e3021894 279 }
elessair 0:f269e3021894 280
elessair 0:f269e3021894 281 int i2c_byte_write(i2c_t *obj, int data)
elessair 0:f269e3021894 282 {
elessair 0:f269e3021894 283 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 284 int timeout;
elessair 0:f269e3021894 285
elessair 0:f269e3021894 286 i2c->DR = (uint8_t)data;
elessair 0:f269e3021894 287
elessair 0:f269e3021894 288 // Wait until the byte is transmitted
elessair 0:f269e3021894 289 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 290 while ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TXE) == RESET) &&
elessair 0:f269e3021894 291 (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BTF) == RESET)) {
elessair 0:f269e3021894 292 if ((timeout--) == 0) {
elessair 0:f269e3021894 293 return 0;
elessair 0:f269e3021894 294 }
elessair 0:f269e3021894 295 }
elessair 0:f269e3021894 296
elessair 0:f269e3021894 297 return 1;
elessair 0:f269e3021894 298 }
elessair 0:f269e3021894 299
elessair 0:f269e3021894 300 void i2c_reset(i2c_t *obj)
elessair 0:f269e3021894 301 {
elessair 0:f269e3021894 302 int timeout;
elessair 0:f269e3021894 303
elessair 0:f269e3021894 304 // wait before reset
elessair 0:f269e3021894 305 timeout = LONG_TIMEOUT;
elessair 0:f269e3021894 306 while ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY)) && (timeout-- != 0));
elessair 0:f269e3021894 307
elessair 0:f269e3021894 308 if (obj->i2c == I2C_1) {
elessair 0:f269e3021894 309 __I2C1_FORCE_RESET();
elessair 0:f269e3021894 310 __I2C1_RELEASE_RESET();
elessair 0:f269e3021894 311 }
elessair 0:f269e3021894 312 if (obj->i2c == I2C_2) {
elessair 0:f269e3021894 313 __I2C2_FORCE_RESET();
elessair 0:f269e3021894 314 __I2C2_RELEASE_RESET();
elessair 0:f269e3021894 315 }
elessair 0:f269e3021894 316 }
elessair 0:f269e3021894 317
elessair 0:f269e3021894 318 #if DEVICE_I2CSLAVE
elessair 0:f269e3021894 319
elessair 0:f269e3021894 320 void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask)
elessair 0:f269e3021894 321 {
elessair 0:f269e3021894 322 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 323 uint16_t tmpreg = 0;
elessair 0:f269e3021894 324
elessair 0:f269e3021894 325 // Get the old register value
elessair 0:f269e3021894 326 tmpreg = i2c->OAR1;
elessair 0:f269e3021894 327 // Reset address bits
elessair 0:f269e3021894 328 tmpreg &= 0xFC00;
elessair 0:f269e3021894 329 // Set new address
elessair 0:f269e3021894 330 tmpreg |= (uint16_t)((uint16_t)address & (uint16_t)0x00FE); // 7-bits
elessair 0:f269e3021894 331 // Store the new register value
elessair 0:f269e3021894 332 i2c->OAR1 = tmpreg;
elessair 0:f269e3021894 333 }
elessair 0:f269e3021894 334
elessair 0:f269e3021894 335 void i2c_slave_mode(i2c_t *obj, int enable_slave)
elessair 0:f269e3021894 336 {
elessair 0:f269e3021894 337 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 338 if (enable_slave) {
elessair 0:f269e3021894 339 obj->slave = 1;
elessair 0:f269e3021894 340 /* Enable Address Acknowledge */
elessair 0:f269e3021894 341 I2cHandle.Instance->CR1 |= I2C_CR1_ACK;
elessair 0:f269e3021894 342 }
elessair 0:f269e3021894 343 }
elessair 0:f269e3021894 344
elessair 0:f269e3021894 345 // See I2CSlave.h
elessair 0:f269e3021894 346 #define NoData 0 // the slave has not been addressed
elessair 0:f269e3021894 347 #define ReadAddressed 1 // the master has requested a read from this slave (slave = transmitter)
elessair 0:f269e3021894 348 #define WriteGeneral 2 // the master is writing to all slave
elessair 0:f269e3021894 349 #define WriteAddressed 3 // the master is writing to this slave (slave = receiver)
elessair 0:f269e3021894 350
elessair 0:f269e3021894 351 int i2c_slave_receive(i2c_t *obj)
elessair 0:f269e3021894 352 {
elessair 0:f269e3021894 353 int retValue = NoData;
elessair 0:f269e3021894 354
elessair 0:f269e3021894 355 if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY) == 1) {
elessair 0:f269e3021894 356 if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_ADDR) == 1) {
elessair 0:f269e3021894 357 if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TRA) == 1)
elessair 0:f269e3021894 358 retValue = ReadAddressed;
elessair 0:f269e3021894 359 else
elessair 0:f269e3021894 360 retValue = WriteAddressed;
elessair 0:f269e3021894 361
elessair 0:f269e3021894 362 __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_ADDR);
elessair 0:f269e3021894 363 }
elessair 0:f269e3021894 364 }
elessair 0:f269e3021894 365
elessair 0:f269e3021894 366 return (retValue);
elessair 0:f269e3021894 367 }
elessair 0:f269e3021894 368
elessair 0:f269e3021894 369 int i2c_slave_read(i2c_t *obj, char *data, int length)
elessair 0:f269e3021894 370 {
elessair 0:f269e3021894 371 uint32_t Timeout;
elessair 0:f269e3021894 372 int size = 0;
elessair 0:f269e3021894 373
elessair 0:f269e3021894 374 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 375
elessair 0:f269e3021894 376 while (length > 0) {
elessair 0:f269e3021894 377 /* Wait until RXNE flag is set */
elessair 0:f269e3021894 378 // Wait until the byte is received
elessair 0:f269e3021894 379 Timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 380 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_RXNE) == RESET) {
elessair 0:f269e3021894 381 Timeout--;
elessair 0:f269e3021894 382 if (Timeout == 0) {
elessair 0:f269e3021894 383 return -1;
elessair 0:f269e3021894 384 }
elessair 0:f269e3021894 385 }
elessair 0:f269e3021894 386
elessair 0:f269e3021894 387 /* Read data from DR */
elessair 0:f269e3021894 388 (*data++) = I2cHandle.Instance->DR;
elessair 0:f269e3021894 389 length--;
elessair 0:f269e3021894 390 size++;
elessair 0:f269e3021894 391
elessair 0:f269e3021894 392 if ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BTF) == SET) && (length != 0)) {
elessair 0:f269e3021894 393 /* Read data from DR */
elessair 0:f269e3021894 394 (*data++) = I2cHandle.Instance->DR;
elessair 0:f269e3021894 395 length--;
elessair 0:f269e3021894 396 size++;
elessair 0:f269e3021894 397 }
elessair 0:f269e3021894 398 }
elessair 0:f269e3021894 399
elessair 0:f269e3021894 400 /* Wait until STOP flag is set */
elessair 0:f269e3021894 401 Timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 402 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_STOPF) == RESET) {
elessair 0:f269e3021894 403 Timeout--;
elessair 0:f269e3021894 404 if (Timeout == 0) {
elessair 0:f269e3021894 405 return -1;
elessair 0:f269e3021894 406 }
elessair 0:f269e3021894 407 }
elessair 0:f269e3021894 408
elessair 0:f269e3021894 409 /* Clear STOP flag */
elessair 0:f269e3021894 410 __HAL_I2C_CLEAR_STOPFLAG(&I2cHandle);
elessair 0:f269e3021894 411
elessair 0:f269e3021894 412 /* Wait until BUSY flag is reset */
elessair 0:f269e3021894 413 Timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 414 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY) == SET) {
elessair 0:f269e3021894 415 Timeout--;
elessair 0:f269e3021894 416 if (Timeout == 0) {
elessair 0:f269e3021894 417 return -1;
elessair 0:f269e3021894 418 }
elessair 0:f269e3021894 419 }
elessair 0:f269e3021894 420
elessair 0:f269e3021894 421 return size;
elessair 0:f269e3021894 422 }
elessair 0:f269e3021894 423
elessair 0:f269e3021894 424 int i2c_slave_write(i2c_t *obj, const char *data, int length)
elessair 0:f269e3021894 425 {
elessair 0:f269e3021894 426 uint32_t Timeout;
elessair 0:f269e3021894 427 int size = 0;
elessair 0:f269e3021894 428
elessair 0:f269e3021894 429 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 430
elessair 0:f269e3021894 431 while (length > 0) {
elessair 0:f269e3021894 432 /* Wait until TXE flag is set */
elessair 0:f269e3021894 433 Timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 434 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TXE) == RESET) {
elessair 0:f269e3021894 435 Timeout--;
elessair 0:f269e3021894 436 if (Timeout == 0) {
elessair 0:f269e3021894 437 return -1;
elessair 0:f269e3021894 438 }
elessair 0:f269e3021894 439 }
elessair 0:f269e3021894 440
elessair 0:f269e3021894 441
elessair 0:f269e3021894 442 /* Write data to DR */
elessair 0:f269e3021894 443 I2cHandle.Instance->DR = (*data++);
elessair 0:f269e3021894 444 length--;
elessair 0:f269e3021894 445 size++;
elessair 0:f269e3021894 446
elessair 0:f269e3021894 447 if ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BTF) == SET) && (length != 0)) {
elessair 0:f269e3021894 448 /* Write data to DR */
elessair 0:f269e3021894 449 I2cHandle.Instance->DR = (*data++);
elessair 0:f269e3021894 450 length--;
elessair 0:f269e3021894 451 size++;
elessair 0:f269e3021894 452 }
elessair 0:f269e3021894 453 }
elessair 0:f269e3021894 454
elessair 0:f269e3021894 455 /* Wait until AF flag is set */
elessair 0:f269e3021894 456 Timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 457 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_AF) == RESET) {
elessair 0:f269e3021894 458 Timeout--;
elessair 0:f269e3021894 459 if (Timeout == 0) {
elessair 0:f269e3021894 460 return -1;
elessair 0:f269e3021894 461 }
elessair 0:f269e3021894 462 }
elessair 0:f269e3021894 463
elessair 0:f269e3021894 464
elessair 0:f269e3021894 465 /* Clear AF flag */
elessair 0:f269e3021894 466 __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_AF);
elessair 0:f269e3021894 467
elessair 0:f269e3021894 468
elessair 0:f269e3021894 469 /* Wait until BUSY flag is reset */
elessair 0:f269e3021894 470 Timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 471 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY) == SET) {
elessair 0:f269e3021894 472 Timeout--;
elessair 0:f269e3021894 473 if (Timeout == 0) {
elessair 0:f269e3021894 474 return -1;
elessair 0:f269e3021894 475 }
elessair 0:f269e3021894 476 }
elessair 0:f269e3021894 477
elessair 0:f269e3021894 478 I2cHandle.State = HAL_I2C_STATE_READY;
elessair 0:f269e3021894 479
elessair 0:f269e3021894 480 /* Process Unlocked */
elessair 0:f269e3021894 481 __HAL_UNLOCK(&I2cHandle);
elessair 0:f269e3021894 482
elessair 0:f269e3021894 483 return size;
elessair 0:f269e3021894 484 }
elessair 0:f269e3021894 485
elessair 0:f269e3021894 486
elessair 0:f269e3021894 487 #endif // DEVICE_I2CSLAVE
elessair 0:f269e3021894 488
elessair 0:f269e3021894 489 #endif // DEVICE_I2C