erkin yucel / mbed-os

mbed os with nrf51 internal bandgap enabled to read battery level

Dependents:   BLE_file_test BLE_Blink ExternalEncoder

targets/TARGET_STM/TARGET_STM32F0/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 #if defined(I2C2_BASE)
elessair 0:f269e3021894 49 int i2c2_inited = 0;
elessair 0:f269e3021894 50 #endif
elessair 0:f269e3021894 51
elessair 0:f269e3021894 52 void i2c_init(i2c_t *obj, PinName sda, PinName scl) {
elessair 0:f269e3021894 53 // Determine the I2C to use
elessair 0:f269e3021894 54 I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA);
elessair 0:f269e3021894 55 I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL);
elessair 0:f269e3021894 56
elessair 0:f269e3021894 57 obj->i2c = (I2CName)pinmap_merge(i2c_sda, i2c_scl);
elessair 0:f269e3021894 58 MBED_ASSERT(obj->i2c != (I2CName)NC);
elessair 0:f269e3021894 59
elessair 0:f269e3021894 60 // Enable I2C1 clock and pinout if not done
elessair 0:f269e3021894 61 if ((obj->i2c == I2C_1) && !i2c1_inited) {
elessair 0:f269e3021894 62 i2c1_inited = 1;
elessair 0:f269e3021894 63 __HAL_RCC_I2C1_CONFIG(RCC_I2C1CLKSOURCE_SYSCLK);
elessair 0:f269e3021894 64 __I2C1_CLK_ENABLE();
elessair 0:f269e3021894 65 // Configure I2C pins
elessair 0:f269e3021894 66 pinmap_pinout(sda, PinMap_I2C_SDA);
elessair 0:f269e3021894 67 pinmap_pinout(scl, PinMap_I2C_SCL);
elessair 0:f269e3021894 68 pin_mode(sda, OpenDrain);
elessair 0:f269e3021894 69 pin_mode(scl, OpenDrain);
elessair 0:f269e3021894 70 }
elessair 0:f269e3021894 71
elessair 0:f269e3021894 72 #if defined(I2C2_BASE)
elessair 0:f269e3021894 73 // Enable I2C2 clock and pinout if not done
elessair 0:f269e3021894 74 if ((obj->i2c == I2C_2) && !i2c2_inited) {
elessair 0:f269e3021894 75 i2c2_inited = 1;
elessair 0:f269e3021894 76 __I2C2_CLK_ENABLE();
elessair 0:f269e3021894 77 // Configure I2C pins
elessair 0:f269e3021894 78 pinmap_pinout(sda, PinMap_I2C_SDA);
elessair 0:f269e3021894 79 pinmap_pinout(scl, PinMap_I2C_SCL);
elessair 0:f269e3021894 80 pin_mode(sda, OpenDrain);
elessair 0:f269e3021894 81 pin_mode(scl, OpenDrain);
elessair 0:f269e3021894 82 }
elessair 0:f269e3021894 83 #endif
elessair 0:f269e3021894 84
elessair 0:f269e3021894 85 // Reset to clear pending flags if any
elessair 0:f269e3021894 86 i2c_reset(obj);
elessair 0:f269e3021894 87
elessair 0:f269e3021894 88 // I2C configuration
elessair 0:f269e3021894 89 i2c_frequency(obj, 100000); // 100 kHz per default
elessair 0:f269e3021894 90 }
elessair 0:f269e3021894 91
elessair 0:f269e3021894 92 void i2c_frequency(i2c_t *obj, int hz) {
elessair 0:f269e3021894 93 MBED_ASSERT((hz == 100000) || (hz == 400000) || (hz == 1000000));
elessair 0:f269e3021894 94 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 95 int timeout;
elessair 0:f269e3021894 96
elessair 0:f269e3021894 97 // wait before init
elessair 0:f269e3021894 98 timeout = LONG_TIMEOUT;
elessair 0:f269e3021894 99 while ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY)) && (timeout-- != 0));
elessair 0:f269e3021894 100
elessair 0:f269e3021894 101 // Common settings: I2C clock = 48 MHz, Analog filter = ON, Digital filter coefficient = 0
elessair 0:f269e3021894 102 switch (hz) {
elessair 0:f269e3021894 103 case 100000:
elessair 0:f269e3021894 104 I2cHandle.Init.Timing = 0x10805E89; // Standard mode with Rise Time = 400ns and Fall Time = 100ns
elessair 0:f269e3021894 105 break;
elessair 0:f269e3021894 106 case 400000:
elessair 0:f269e3021894 107 I2cHandle.Init.Timing = 0x00901850; // Fast mode with Rise Time = 250ns and Fall Time = 100ns
elessair 0:f269e3021894 108 break;
elessair 0:f269e3021894 109 case 1000000:
elessair 0:f269e3021894 110 I2cHandle.Init.Timing = 0x00700818; // Fast mode Plus with Rise Time = 60ns and Fall Time = 100ns
elessair 0:f269e3021894 111 break;
elessair 0:f269e3021894 112 default:
elessair 0:f269e3021894 113 break;
elessair 0:f269e3021894 114 }
elessair 0:f269e3021894 115
elessair 0:f269e3021894 116 // I2C configuration
elessair 0:f269e3021894 117 I2cHandle.Init.AddressingMode = I2C_ADDRESSINGMODE_7BIT;
elessair 0:f269e3021894 118 I2cHandle.Init.DualAddressMode = I2C_DUALADDRESS_DISABLED;
elessair 0:f269e3021894 119 I2cHandle.Init.GeneralCallMode = I2C_GENERALCALL_DISABLED;
elessair 0:f269e3021894 120 I2cHandle.Init.NoStretchMode = I2C_NOSTRETCH_DISABLED;
elessair 0:f269e3021894 121 I2cHandle.Init.OwnAddress1 = 0;
elessair 0:f269e3021894 122 I2cHandle.Init.OwnAddress2 = 0;
elessair 0:f269e3021894 123 I2cHandle.Init.OwnAddress2Masks = I2C_OA2_NOMASK;
elessair 0:f269e3021894 124 HAL_I2C_Init(&I2cHandle);
elessair 0:f269e3021894 125 }
elessair 0:f269e3021894 126
elessair 0:f269e3021894 127 inline int i2c_start(i2c_t *obj) {
elessair 0:f269e3021894 128 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 129 int timeout;
elessair 0:f269e3021894 130
elessair 0:f269e3021894 131 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 132
elessair 0:f269e3021894 133 // Clear Acknowledge failure flag
elessair 0:f269e3021894 134 __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_AF);
elessair 0:f269e3021894 135
elessair 0:f269e3021894 136 // Wait the STOP condition has been previously correctly sent
elessair 0:f269e3021894 137 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 138 while ((i2c->CR2 & I2C_CR2_STOP) == I2C_CR2_STOP){
elessair 0:f269e3021894 139 if ((timeout--) == 0) {
elessair 0:f269e3021894 140 return 1;
elessair 0:f269e3021894 141 }
elessair 0:f269e3021894 142 }
elessair 0:f269e3021894 143
elessair 0:f269e3021894 144 // Generate the START condition
elessair 0:f269e3021894 145 i2c->CR2 |= I2C_CR2_START;
elessair 0:f269e3021894 146
elessair 0:f269e3021894 147 // Wait the START condition has been correctly sent
elessair 0:f269e3021894 148 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 149 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY) == RESET) {
elessair 0:f269e3021894 150 if ((timeout--) == 0) {
elessair 0:f269e3021894 151 return 1;
elessair 0:f269e3021894 152 }
elessair 0:f269e3021894 153 }
elessair 0:f269e3021894 154
elessair 0:f269e3021894 155 return 0;
elessair 0:f269e3021894 156 }
elessair 0:f269e3021894 157
elessair 0:f269e3021894 158 inline int i2c_stop(i2c_t *obj) {
elessair 0:f269e3021894 159 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 160
elessair 0:f269e3021894 161 // Generate the STOP condition
elessair 0:f269e3021894 162 i2c->CR2 |= I2C_CR2_STOP;
elessair 0:f269e3021894 163
elessair 0:f269e3021894 164 return 0;
elessair 0:f269e3021894 165 }
elessair 0:f269e3021894 166
elessair 0:f269e3021894 167 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) {
elessair 0:f269e3021894 168 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 169 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 170 int timeout;
elessair 0:f269e3021894 171 int count;
elessair 0:f269e3021894 172 int value;
elessair 0:f269e3021894 173
elessair 0:f269e3021894 174 // Update CR2 register
elessair 0:f269e3021894 175 i2c->CR2 = (i2c->CR2 & (uint32_t)~((uint32_t)(I2C_CR2_SADD | I2C_CR2_NBYTES | I2C_CR2_RELOAD | I2C_CR2_AUTOEND | I2C_CR2_RD_WRN | I2C_CR2_START | I2C_CR2_STOP)))
elessair 0:f269e3021894 176 | (uint32_t)(((uint32_t)address & I2C_CR2_SADD) | (((uint32_t)length << 16) & I2C_CR2_NBYTES) | (uint32_t)I2C_SOFTEND_MODE | (uint32_t)I2C_GENERATE_START_READ);
elessair 0:f269e3021894 177
elessair 0:f269e3021894 178 // Read all bytes
elessair 0:f269e3021894 179 for (count = 0; count < length; count++) {
elessair 0:f269e3021894 180 value = i2c_byte_read(obj, 0);
elessair 0:f269e3021894 181 data[count] = (char)value;
elessair 0:f269e3021894 182 }
elessair 0:f269e3021894 183
elessair 0:f269e3021894 184 // Wait transfer complete
elessair 0:f269e3021894 185 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 186 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TC) == RESET) {
elessair 0:f269e3021894 187 timeout--;
elessair 0:f269e3021894 188 if (timeout == 0) {
elessair 0:f269e3021894 189 return -1;
elessair 0:f269e3021894 190 }
elessair 0:f269e3021894 191 }
elessair 0:f269e3021894 192 __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_TC);
elessair 0:f269e3021894 193
elessair 0:f269e3021894 194 // If not repeated start, send stop.
elessair 0:f269e3021894 195 if (stop) {
elessair 0:f269e3021894 196 i2c_stop(obj);
elessair 0:f269e3021894 197 // Wait until STOPF flag is set
elessair 0:f269e3021894 198 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 199 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_STOPF) == RESET) {
elessair 0:f269e3021894 200 timeout--;
elessair 0:f269e3021894 201 if (timeout == 0) {
elessair 0:f269e3021894 202 return -1;
elessair 0:f269e3021894 203 }
elessair 0:f269e3021894 204 }
elessair 0:f269e3021894 205 // Clear STOP Flag
elessair 0:f269e3021894 206 __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_STOPF);
elessair 0:f269e3021894 207 }
elessair 0:f269e3021894 208
elessair 0:f269e3021894 209 return length;
elessair 0:f269e3021894 210 }
elessair 0:f269e3021894 211
elessair 0:f269e3021894 212 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) {
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 // Update CR2 register
elessair 0:f269e3021894 219 i2c->CR2 = (i2c->CR2 & (uint32_t)~((uint32_t)(I2C_CR2_SADD | I2C_CR2_NBYTES | I2C_CR2_RELOAD | I2C_CR2_AUTOEND | I2C_CR2_RD_WRN | I2C_CR2_START | I2C_CR2_STOP)))
elessair 0:f269e3021894 220 | (uint32_t)(((uint32_t)address & I2C_CR2_SADD) | (((uint32_t)length << 16) & I2C_CR2_NBYTES) | (uint32_t)I2C_SOFTEND_MODE | (uint32_t)I2C_GENERATE_START_WRITE);
elessair 0:f269e3021894 221
elessair 0:f269e3021894 222 for (count = 0; count < length; count++) {
elessair 0:f269e3021894 223 i2c_byte_write(obj, data[count]);
elessair 0:f269e3021894 224 }
elessair 0:f269e3021894 225
elessair 0:f269e3021894 226 // Wait transfer complete
elessair 0:f269e3021894 227 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 228 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TC) == RESET) {
elessair 0:f269e3021894 229 timeout--;
elessair 0:f269e3021894 230 if (timeout == 0) {
elessair 0:f269e3021894 231 return -1;
elessair 0:f269e3021894 232 }
elessair 0:f269e3021894 233 }
elessair 0:f269e3021894 234 __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_TC);
elessair 0:f269e3021894 235
elessair 0:f269e3021894 236 // If not repeated start, send stop
elessair 0:f269e3021894 237 if (stop) {
elessair 0:f269e3021894 238 i2c_stop(obj);
elessair 0:f269e3021894 239 // Wait until STOPF flag is set
elessair 0:f269e3021894 240 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 241 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_STOPF) == RESET) {
elessair 0:f269e3021894 242 timeout--;
elessair 0:f269e3021894 243 if (timeout == 0) {
elessair 0:f269e3021894 244 return -1;
elessair 0:f269e3021894 245 }
elessair 0:f269e3021894 246 }
elessair 0:f269e3021894 247 // Clear STOP Flag
elessair 0:f269e3021894 248 __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_STOPF);
elessair 0:f269e3021894 249 }
elessair 0:f269e3021894 250
elessair 0:f269e3021894 251 return count;
elessair 0:f269e3021894 252 }
elessair 0:f269e3021894 253
elessair 0:f269e3021894 254 int i2c_byte_read(i2c_t *obj, int last) {
elessair 0:f269e3021894 255 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 256 int timeout;
elessair 0:f269e3021894 257
elessair 0:f269e3021894 258 // Wait until the byte is received
elessair 0:f269e3021894 259 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 260 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_RXNE) == RESET) {
elessair 0:f269e3021894 261 if ((timeout--) == 0) {
elessair 0:f269e3021894 262 return -1;
elessair 0:f269e3021894 263 }
elessair 0:f269e3021894 264 }
elessair 0:f269e3021894 265
elessair 0:f269e3021894 266 return (int)i2c->RXDR;
elessair 0:f269e3021894 267 }
elessair 0:f269e3021894 268
elessair 0:f269e3021894 269 int i2c_byte_write(i2c_t *obj, int data) {
elessair 0:f269e3021894 270 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 271 int timeout;
elessair 0:f269e3021894 272
elessair 0:f269e3021894 273 // Wait until the previous byte is transmitted
elessair 0:f269e3021894 274 timeout = FLAG_TIMEOUT;
elessair 0:f269e3021894 275 while (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_TXIS) == RESET) {
elessair 0:f269e3021894 276 if ((timeout--) == 0) {
elessair 0:f269e3021894 277 return 0;
elessair 0:f269e3021894 278 }
elessair 0:f269e3021894 279 }
elessair 0:f269e3021894 280
elessair 0:f269e3021894 281 i2c->TXDR = (uint8_t)data;
elessair 0:f269e3021894 282
elessair 0:f269e3021894 283 return 1;
elessair 0:f269e3021894 284 }
elessair 0:f269e3021894 285
elessair 0:f269e3021894 286 void i2c_reset(i2c_t *obj) {
elessair 0:f269e3021894 287 int timeout;
elessair 0:f269e3021894 288
elessair 0:f269e3021894 289 // Wait before reset
elessair 0:f269e3021894 290 timeout = LONG_TIMEOUT;
elessair 0:f269e3021894 291 while ((__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY)) && (timeout-- != 0));
elessair 0:f269e3021894 292
elessair 0:f269e3021894 293 if (obj->i2c == I2C_1) {
elessair 0:f269e3021894 294 __I2C1_FORCE_RESET();
elessair 0:f269e3021894 295 __I2C1_RELEASE_RESET();
elessair 0:f269e3021894 296 }
elessair 0:f269e3021894 297 #if defined(I2C2_BASE)
elessair 0:f269e3021894 298 if (obj->i2c == I2C_2) {
elessair 0:f269e3021894 299 __I2C2_FORCE_RESET();
elessair 0:f269e3021894 300 __I2C2_RELEASE_RESET();
elessair 0:f269e3021894 301 }
elessair 0:f269e3021894 302 #endif
elessair 0:f269e3021894 303 }
elessair 0:f269e3021894 304
elessair 0:f269e3021894 305 #if DEVICE_I2CSLAVE
elessair 0:f269e3021894 306
elessair 0:f269e3021894 307 void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask) {
elessair 0:f269e3021894 308 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 309 uint16_t tmpreg = 0;
elessair 0:f269e3021894 310
elessair 0:f269e3021894 311 // disable
elessair 0:f269e3021894 312 i2c->OAR1 &= (uint32_t)(~I2C_OAR1_OA1EN);
elessair 0:f269e3021894 313 // Get the old register value
elessair 0:f269e3021894 314 tmpreg = i2c->OAR1;
elessair 0:f269e3021894 315 // Reset address bits
elessair 0:f269e3021894 316 tmpreg &= 0xFC00;
elessair 0:f269e3021894 317 // Set new address
elessair 0:f269e3021894 318 tmpreg |= (uint16_t)((uint16_t)address & (uint16_t)0x00FE); // 7-bits
elessair 0:f269e3021894 319 // Store the new register value
elessair 0:f269e3021894 320 i2c->OAR1 = tmpreg;
elessair 0:f269e3021894 321 // enable
elessair 0:f269e3021894 322 i2c->OAR1 |= I2C_OAR1_OA1EN;
elessair 0:f269e3021894 323 }
elessair 0:f269e3021894 324
elessair 0:f269e3021894 325 void i2c_slave_mode(i2c_t *obj, int enable_slave) {
elessair 0:f269e3021894 326 I2C_TypeDef *i2c = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 327 uint16_t tmpreg;
elessair 0:f269e3021894 328
elessair 0:f269e3021894 329 // Get the old register value
elessair 0:f269e3021894 330 tmpreg = i2c->OAR1;
elessair 0:f269e3021894 331
elessair 0:f269e3021894 332 // Enable / disable slave
elessair 0:f269e3021894 333 if (enable_slave == 1) {
elessair 0:f269e3021894 334 tmpreg |= I2C_OAR1_OA1EN;
elessair 0:f269e3021894 335 } else {
elessair 0:f269e3021894 336 tmpreg &= (uint32_t)(~I2C_OAR1_OA1EN);
elessair 0:f269e3021894 337 }
elessair 0:f269e3021894 338
elessair 0:f269e3021894 339 // Set new mode
elessair 0:f269e3021894 340 i2c->OAR1 = tmpreg;
elessair 0:f269e3021894 341 }
elessair 0:f269e3021894 342
elessair 0:f269e3021894 343 // See I2CSlave.h
elessair 0:f269e3021894 344 #define NoData 0 // the slave has not been addressed
elessair 0:f269e3021894 345 #define ReadAddressed 1 // the master has requested a read from this slave (slave = transmitter)
elessair 0:f269e3021894 346 #define WriteGeneral 2 // the master is writing to all slave
elessair 0:f269e3021894 347 #define WriteAddressed 3 // the master is writing to this slave (slave = receiver)
elessair 0:f269e3021894 348
elessair 0:f269e3021894 349 int i2c_slave_receive(i2c_t *obj) {
elessair 0:f269e3021894 350 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 351 int retValue = NoData;
elessair 0:f269e3021894 352
elessair 0:f269e3021894 353 if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_BUSY) == 1) {
elessair 0:f269e3021894 354 if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_ADDR) == 1) {
elessair 0:f269e3021894 355 if (__HAL_I2C_GET_FLAG(&I2cHandle, I2C_FLAG_DIR) == 1)
elessair 0:f269e3021894 356 retValue = ReadAddressed;
elessair 0:f269e3021894 357 else
elessair 0:f269e3021894 358 retValue = WriteAddressed;
elessair 0:f269e3021894 359
elessair 0:f269e3021894 360 __HAL_I2C_CLEAR_FLAG(&I2cHandle, I2C_FLAG_ADDR);
elessair 0:f269e3021894 361 }
elessair 0:f269e3021894 362 }
elessair 0:f269e3021894 363
elessair 0:f269e3021894 364 return (retValue);
elessair 0:f269e3021894 365 }
elessair 0:f269e3021894 366
elessair 0:f269e3021894 367 int i2c_slave_read(i2c_t *obj, char *data, int length) {
elessair 0:f269e3021894 368 char size = 0;
elessair 0:f269e3021894 369
elessair 0:f269e3021894 370 while (size < length) data[size++] = (char)i2c_byte_read(obj, 0);
elessair 0:f269e3021894 371
elessair 0:f269e3021894 372 return size;
elessair 0:f269e3021894 373 }
elessair 0:f269e3021894 374
elessair 0:f269e3021894 375 int i2c_slave_write(i2c_t *obj, const char *data, int length) {
elessair 0:f269e3021894 376 char size = 0;
elessair 0:f269e3021894 377 I2cHandle.Instance = (I2C_TypeDef *)(obj->i2c);
elessair 0:f269e3021894 378
elessair 0:f269e3021894 379 do {
elessair 0:f269e3021894 380 i2c_byte_write(obj, data[size]);
elessair 0:f269e3021894 381 size++;
elessair 0:f269e3021894 382 } while (size < length);
elessair 0:f269e3021894 383
elessair 0:f269e3021894 384 return size;
elessair 0:f269e3021894 385 }
elessair 0:f269e3021894 386
elessair 0:f269e3021894 387
elessair 0:f269e3021894 388 #endif // DEVICE_I2CSLAVE
elessair 0:f269e3021894 389
elessair 0:f269e3021894 390 #endif // DEVICE_I2C