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mbed-os/targets/TARGET_NXP/TARGET_LPC43XX/i2c_api.c@2:c7897a3f5f11, 2020-04-22 (annotated)

Committer:
demayer
Date:
Wed Apr 22 11:50:00 2020 +0000
Revision:
2:c7897a3f5f11
Parent:
0:6bf0743ece18 
test

Who changed what in which revision?

UserRevisionLine numberNew contents of line
demayer 0:6bf0743ece18 1 /* mbed Microcontroller Library
demayer 0:6bf0743ece18 2 * Copyright (c) 2006-2013 ARM Limited
demayer 0:6bf0743ece18 3 *
demayer 0:6bf0743ece18 4 * Licensed under the Apache License, Version 2.0 (the "License");
demayer 0:6bf0743ece18 5 * you may not use this file except in compliance with the License.
demayer 0:6bf0743ece18 6 * You may obtain a copy of the License at
demayer 0:6bf0743ece18 7 *
demayer 0:6bf0743ece18 8 * http://www.apache.org/licenses/LICENSE-2.0
demayer 0:6bf0743ece18 9 *
demayer 0:6bf0743ece18 10 * Unless required by applicable law or agreed to in writing, software
demayer 0:6bf0743ece18 11 * distributed under the License is distributed on an "AS IS" BASIS,
demayer 0:6bf0743ece18 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
demayer 0:6bf0743ece18 13 * See the License for the specific language governing permissions and
demayer 0:6bf0743ece18 14 * limitations under the License.
demayer 0:6bf0743ece18 15 *
demayer 0:6bf0743ece18 16 * Ported to NXP LPC43XX by Micromint USA <support@micromint.com>
demayer 0:6bf0743ece18 17 */
demayer 0:6bf0743ece18 18 #include "i2c_api.h"
demayer 0:6bf0743ece18 19 #include "cmsis.h"
demayer 0:6bf0743ece18 20 #include "pinmap.h"
demayer 0:6bf0743ece18 21 #include "mbed_error.h"
demayer 0:6bf0743ece18 22
demayer 0:6bf0743ece18 23 // SCU mode for I2C SCL/SDA pins
demayer 0:6bf0743ece18 24 #define SCU_PINIO_I2C SCU_PINIO_PULLNONE
demayer 0:6bf0743ece18 25
demayer 0:6bf0743ece18 26 static const PinMap PinMap_I2C_SDA[] = {
demayer 0:6bf0743ece18 27 {P_DED, I2C_0, 0},
demayer 0:6bf0743ece18 28 {P2_3, I2C_1, (SCU_PINIO_I2C | 1)},
demayer 0:6bf0743ece18 29 {PE_13, I2C_1, (SCU_PINIO_I2C | 2)},
demayer 0:6bf0743ece18 30 {NC, NC, 0}
demayer 0:6bf0743ece18 31 };
demayer 0:6bf0743ece18 32
demayer 0:6bf0743ece18 33 static const PinMap PinMap_I2C_SCL[] = {
demayer 0:6bf0743ece18 34 {P_DED, I2C_0, 0},
demayer 0:6bf0743ece18 35 {P2_4, I2C_1, (SCU_PINIO_I2C | 1)},
demayer 0:6bf0743ece18 36 {PE_14, I2C_1, (SCU_PINIO_I2C | 2)},
demayer 0:6bf0743ece18 37 {NC, NC, 0}
demayer 0:6bf0743ece18 38 };
demayer 0:6bf0743ece18 39
demayer 0:6bf0743ece18 40 #define I2C_CONSET(x) (x->i2c->CONSET)
demayer 0:6bf0743ece18 41 #define I2C_CONCLR(x) (x->i2c->CONCLR)
demayer 0:6bf0743ece18 42 #define I2C_STAT(x) (x->i2c->STAT)
demayer 0:6bf0743ece18 43 #define I2C_DAT(x) (x->i2c->DAT)
demayer 0:6bf0743ece18 44 #define I2C_SCLL(x, val) (x->i2c->SCLL = val)
demayer 0:6bf0743ece18 45 #define I2C_SCLH(x, val) (x->i2c->SCLH = val)
demayer 0:6bf0743ece18 46
demayer 0:6bf0743ece18 47 static const uint32_t I2C_addr_offset[2][4] = {
demayer 0:6bf0743ece18 48 {0x0C, 0x20, 0x24, 0x28},
demayer 0:6bf0743ece18 49 {0x30, 0x34, 0x38, 0x3C}
demayer 0:6bf0743ece18 50 };
demayer 0:6bf0743ece18 51
demayer 0:6bf0743ece18 52 static inline void i2c_conclr(i2c_t *obj, int start, int stop, int interrupt, int acknowledge) {
demayer 0:6bf0743ece18 53 I2C_CONCLR(obj) = (start << 5)
demayer 0:6bf0743ece18 54 | (stop << 4)
demayer 0:6bf0743ece18 55 | (interrupt << 3)
demayer 0:6bf0743ece18 56 | (acknowledge << 2);
demayer 0:6bf0743ece18 57 }
demayer 0:6bf0743ece18 58
demayer 0:6bf0743ece18 59 static inline void i2c_conset(i2c_t *obj, int start, int stop, int interrupt, int acknowledge) {
demayer 0:6bf0743ece18 60 I2C_CONSET(obj) = (start << 5)
demayer 0:6bf0743ece18 61 | (stop << 4)
demayer 0:6bf0743ece18 62 | (interrupt << 3)
demayer 0:6bf0743ece18 63 | (acknowledge << 2);
demayer 0:6bf0743ece18 64 }
demayer 0:6bf0743ece18 65
demayer 0:6bf0743ece18 66 // Clear the Serial Interrupt (SI)
demayer 0:6bf0743ece18 67 static inline void i2c_clear_SI(i2c_t *obj) {
demayer 0:6bf0743ece18 68 i2c_conclr(obj, 0, 0, 1, 0);
demayer 0:6bf0743ece18 69 }
demayer 0:6bf0743ece18 70
demayer 0:6bf0743ece18 71 static inline int i2c_status(i2c_t *obj) {
demayer 0:6bf0743ece18 72 return I2C_STAT(obj);
demayer 0:6bf0743ece18 73 }
demayer 0:6bf0743ece18 74
demayer 0:6bf0743ece18 75 // Wait until the Serial Interrupt (SI) is set
demayer 0:6bf0743ece18 76 static int i2c_wait_SI(i2c_t *obj) {
demayer 0:6bf0743ece18 77 int timeout = 0;
demayer 0:6bf0743ece18 78 while (!(I2C_CONSET(obj) & (1 << 3))) {
demayer 0:6bf0743ece18 79 timeout++;
demayer 0:6bf0743ece18 80 if (timeout > 100000) return -1;
demayer 0:6bf0743ece18 81 }
demayer 0:6bf0743ece18 82 return 0;
demayer 0:6bf0743ece18 83 }
demayer 0:6bf0743ece18 84
demayer 0:6bf0743ece18 85 static inline void i2c_interface_enable(i2c_t *obj) {
demayer 0:6bf0743ece18 86 I2C_CONSET(obj) = 0x40;
demayer 0:6bf0743ece18 87 }
demayer 0:6bf0743ece18 88
demayer 0:6bf0743ece18 89 void i2c_init(i2c_t *obj, PinName sda, PinName scl) {
demayer 0:6bf0743ece18 90 // determine the SPI to use
demayer 0:6bf0743ece18 91 I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA);
demayer 0:6bf0743ece18 92 I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL);
demayer 0:6bf0743ece18 93 obj->i2c = (LPC_I2C_T *)pinmap_merge(i2c_sda, i2c_scl);
demayer 0:6bf0743ece18 94
demayer 0:6bf0743ece18 95 if ((int)obj->i2c == NC) {
demayer 0:6bf0743ece18 96 error("I2C pin mapping failed");
demayer 0:6bf0743ece18 97 }
demayer 0:6bf0743ece18 98
demayer 0:6bf0743ece18 99 // set default frequency at 100k
demayer 0:6bf0743ece18 100 i2c_frequency(obj, 100000);
demayer 0:6bf0743ece18 101 i2c_conclr(obj, 1, 1, 1, 1);
demayer 0:6bf0743ece18 102 i2c_interface_enable(obj);
demayer 0:6bf0743ece18 103
demayer 0:6bf0743ece18 104 // Set SCU functions
demayer 0:6bf0743ece18 105 if (scl == P_DED) {
demayer 0:6bf0743ece18 106 // Enable dedicated I2C0 SDA and SCL pins (open drain)
demayer 0:6bf0743ece18 107 LPC_SCU->SFSI2C0 = (1 << 11) | (1 << 3);
demayer 0:6bf0743ece18 108 } else {
demayer 0:6bf0743ece18 109 pinmap_pinout(sda, PinMap_I2C_SDA);
demayer 0:6bf0743ece18 110 pinmap_pinout(scl, PinMap_I2C_SCL);
demayer 0:6bf0743ece18 111 }
demayer 0:6bf0743ece18 112 }
demayer 0:6bf0743ece18 113
demayer 0:6bf0743ece18 114 inline int i2c_start(i2c_t *obj) {
demayer 0:6bf0743ece18 115 int status = 0;
demayer 0:6bf0743ece18 116 int isInterrupted = I2C_CONSET(obj) & (1 << 3);
demayer 0:6bf0743ece18 117
demayer 0:6bf0743ece18 118 // 8.1 Before master mode can be entered, I2CON must be initialised to:
demayer 0:6bf0743ece18 119 // - I2EN STA STO SI AA - -
demayer 0:6bf0743ece18 120 // - 1 0 0 x x - -
demayer 0:6bf0743ece18 121 // if AA = 0, it can't enter slave mode
demayer 0:6bf0743ece18 122 i2c_conclr(obj, 1, 1, 0, 1);
demayer 0:6bf0743ece18 123
demayer 0:6bf0743ece18 124 // The master mode may now be entered by setting the STA bit
demayer 0:6bf0743ece18 125 // this will generate a start condition when the bus becomes free
demayer 0:6bf0743ece18 126 i2c_conset(obj, 1, 0, 0, 1);
demayer 0:6bf0743ece18 127 // Clearing SI bit when it wasn't set on entry can jump past state
demayer 0:6bf0743ece18 128 // 0x10 or 0x08 and erroneously send uninitialized slave address.
demayer 0:6bf0743ece18 129 if (isInterrupted)
demayer 0:6bf0743ece18 130 i2c_clear_SI(obj);
demayer 0:6bf0743ece18 131
demayer 0:6bf0743ece18 132 i2c_wait_SI(obj);
demayer 0:6bf0743ece18 133 status = i2c_status(obj);
demayer 0:6bf0743ece18 134
demayer 0:6bf0743ece18 135 // Clear start bit now that it's transmitted
demayer 0:6bf0743ece18 136 i2c_conclr(obj, 1, 0, 0, 0);
demayer 0:6bf0743ece18 137 return status;
demayer 0:6bf0743ece18 138 }
demayer 0:6bf0743ece18 139
demayer 0:6bf0743ece18 140 inline int i2c_stop(i2c_t *obj) {
demayer 0:6bf0743ece18 141 int timeout = 0;
demayer 0:6bf0743ece18 142
demayer 0:6bf0743ece18 143 // write the stop bit
demayer 0:6bf0743ece18 144 i2c_conset(obj, 0, 1, 0, 0);
demayer 0:6bf0743ece18 145 i2c_clear_SI(obj);
demayer 0:6bf0743ece18 146
demayer 0:6bf0743ece18 147 // wait for STO bit to reset
demayer 0:6bf0743ece18 148 while(I2C_CONSET(obj) & (1 << 4)) {
demayer 0:6bf0743ece18 149 timeout ++;
demayer 0:6bf0743ece18 150 if (timeout > 100000) return 1;
demayer 0:6bf0743ece18 151 }
demayer 0:6bf0743ece18 152
demayer 0:6bf0743ece18 153 return 0;
demayer 0:6bf0743ece18 154 }
demayer 0:6bf0743ece18 155
demayer 0:6bf0743ece18 156 static inline int i2c_do_write(i2c_t *obj, int value, uint8_t addr) {
demayer 0:6bf0743ece18 157 // write the data
demayer 0:6bf0743ece18 158 I2C_DAT(obj) = value;
demayer 0:6bf0743ece18 159
demayer 0:6bf0743ece18 160 // clear SI to init a send
demayer 0:6bf0743ece18 161 i2c_clear_SI(obj);
demayer 0:6bf0743ece18 162
demayer 0:6bf0743ece18 163 // wait and return status
demayer 0:6bf0743ece18 164 i2c_wait_SI(obj);
demayer 0:6bf0743ece18 165 return i2c_status(obj);
demayer 0:6bf0743ece18 166 }
demayer 0:6bf0743ece18 167
demayer 0:6bf0743ece18 168 static inline int i2c_do_read(i2c_t *obj, int last) {
demayer 0:6bf0743ece18 169 // we are in state 0x40 (SLA+R tx'd) or 0x50 (data rx'd and ack)
demayer 0:6bf0743ece18 170 if(last) {
demayer 0:6bf0743ece18 171 i2c_conclr(obj, 0, 0, 0, 1); // send a NOT ACK
demayer 0:6bf0743ece18 172 } else {
demayer 0:6bf0743ece18 173 i2c_conset(obj, 0, 0, 0, 1); // send a ACK
demayer 0:6bf0743ece18 174 }
demayer 0:6bf0743ece18 175
demayer 0:6bf0743ece18 176 // accept byte
demayer 0:6bf0743ece18 177 i2c_clear_SI(obj);
demayer 0:6bf0743ece18 178
demayer 0:6bf0743ece18 179 // wait for it to arrive
demayer 0:6bf0743ece18 180 i2c_wait_SI(obj);
demayer 0:6bf0743ece18 181
demayer 0:6bf0743ece18 182 // return the data
demayer 0:6bf0743ece18 183 return (I2C_DAT(obj) & 0xFF);
demayer 0:6bf0743ece18 184 }
demayer 0:6bf0743ece18 185
demayer 0:6bf0743ece18 186 void i2c_frequency(i2c_t *obj, int hz) {
demayer 0:6bf0743ece18 187 // [TODO] set pclk to /4
demayer 0:6bf0743ece18 188 uint32_t PCLK = SystemCoreClock / 4;
demayer 0:6bf0743ece18 189
demayer 0:6bf0743ece18 190 uint32_t pulse = PCLK / (hz * 2);
demayer 0:6bf0743ece18 191
demayer 0:6bf0743ece18 192 // I2C Rate
demayer 0:6bf0743ece18 193 I2C_SCLL(obj, pulse);
demayer 0:6bf0743ece18 194 I2C_SCLH(obj, pulse);
demayer 0:6bf0743ece18 195 }
demayer 0:6bf0743ece18 196
demayer 0:6bf0743ece18 197 // The I2C does a read or a write as a whole operation
demayer 0:6bf0743ece18 198 // There are two types of error conditions it can encounter
demayer 0:6bf0743ece18 199 // 1) it can not obtain the bus
demayer 0:6bf0743ece18 200 // 2) it gets error responses at part of the transmission
demayer 0:6bf0743ece18 201 //
demayer 0:6bf0743ece18 202 // We tackle them as follows:
demayer 0:6bf0743ece18 203 // 1) we retry until we get the bus. we could have a "timeout" if we can not get it
demayer 0:6bf0743ece18 204 // which basically turns it in to a 2)
demayer 0:6bf0743ece18 205 // 2) on error, we use the standard error mechanisms to report/debug
demayer 0:6bf0743ece18 206 //
demayer 0:6bf0743ece18 207 // Therefore an I2C transaction should always complete. If it doesn't it is usually
demayer 0:6bf0743ece18 208 // because something is setup wrong (e.g. wiring), and we don't need to programatically
demayer 0:6bf0743ece18 209 // check for that
demayer 0:6bf0743ece18 210
demayer 0:6bf0743ece18 211 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) {
demayer 0:6bf0743ece18 212 int count, status;
demayer 0:6bf0743ece18 213
demayer 0:6bf0743ece18 214 status = i2c_start(obj);
demayer 0:6bf0743ece18 215
demayer 0:6bf0743ece18 216 if ((status != 0x10) && (status != 0x08)) {
demayer 0:6bf0743ece18 217 i2c_stop(obj);
demayer 0:6bf0743ece18 218 return I2C_ERROR_BUS_BUSY;
demayer 0:6bf0743ece18 219 }
demayer 0:6bf0743ece18 220
demayer 0:6bf0743ece18 221 status = i2c_do_write(obj, (address | 0x01), 1);
demayer 0:6bf0743ece18 222 if (status != 0x40) {
demayer 0:6bf0743ece18 223 i2c_stop(obj);
demayer 0:6bf0743ece18 224 return I2C_ERROR_NO_SLAVE;
demayer 0:6bf0743ece18 225 }
demayer 0:6bf0743ece18 226
demayer 0:6bf0743ece18 227 // Read in all except last byte
demayer 0:6bf0743ece18 228 for (count = 0; count < (length - 1); count++) {
demayer 0:6bf0743ece18 229 int value = i2c_do_read(obj, 0);
demayer 0:6bf0743ece18 230 status = i2c_status(obj);
demayer 0:6bf0743ece18 231 if (status != 0x50) {
demayer 0:6bf0743ece18 232 i2c_stop(obj);
demayer 0:6bf0743ece18 233 return count;
demayer 0:6bf0743ece18 234 }
demayer 0:6bf0743ece18 235 data[count] = (char) value;
demayer 0:6bf0743ece18 236 }
demayer 0:6bf0743ece18 237
demayer 0:6bf0743ece18 238 // read in last byte
demayer 0:6bf0743ece18 239 int value = i2c_do_read(obj, 1);
demayer 0:6bf0743ece18 240 status = i2c_status(obj);
demayer 0:6bf0743ece18 241 if (status != 0x58) {
demayer 0:6bf0743ece18 242 i2c_stop(obj);
demayer 0:6bf0743ece18 243 return length - 1;
demayer 0:6bf0743ece18 244 }
demayer 0:6bf0743ece18 245
demayer 0:6bf0743ece18 246 data[count] = (char) value;
demayer 0:6bf0743ece18 247
demayer 0:6bf0743ece18 248 // If not repeated start, send stop.
demayer 0:6bf0743ece18 249 if (stop) {
demayer 0:6bf0743ece18 250 i2c_stop(obj);
demayer 0:6bf0743ece18 251 }
demayer 0:6bf0743ece18 252
demayer 0:6bf0743ece18 253 return length;
demayer 0:6bf0743ece18 254 }
demayer 0:6bf0743ece18 255
demayer 0:6bf0743ece18 256 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) {
demayer 0:6bf0743ece18 257 int i, status;
demayer 0:6bf0743ece18 258
demayer 0:6bf0743ece18 259 status = i2c_start(obj);
demayer 0:6bf0743ece18 260
demayer 0:6bf0743ece18 261 if ((status != 0x10) && (status != 0x08)) {
demayer 0:6bf0743ece18 262 i2c_stop(obj);
demayer 0:6bf0743ece18 263 return I2C_ERROR_BUS_BUSY;
demayer 0:6bf0743ece18 264 }
demayer 0:6bf0743ece18 265
demayer 0:6bf0743ece18 266 status = i2c_do_write(obj, (address & 0xFE), 1);
demayer 0:6bf0743ece18 267 if (status != 0x18) {
demayer 0:6bf0743ece18 268 i2c_stop(obj);
demayer 0:6bf0743ece18 269 return I2C_ERROR_NO_SLAVE;
demayer 0:6bf0743ece18 270 }
demayer 0:6bf0743ece18 271
demayer 0:6bf0743ece18 272 for (i=0; i<length; i++) {
demayer 0:6bf0743ece18 273 status = i2c_do_write(obj, data[i], 0);
demayer 0:6bf0743ece18 274 if(status != 0x28) {
demayer 0:6bf0743ece18 275 i2c_stop(obj);
demayer 0:6bf0743ece18 276 return i;
demayer 0:6bf0743ece18 277 }
demayer 0:6bf0743ece18 278 }
demayer 0:6bf0743ece18 279
demayer 0:6bf0743ece18 280 // clearing the serial interrupt here might cause an unintended rewrite of the last byte
demayer 0:6bf0743ece18 281 // see also issue report https://mbed.org/users/mbed_official/code/mbed/issues/1
demayer 0:6bf0743ece18 282 // i2c_clear_SI(obj);
demayer 0:6bf0743ece18 283
demayer 0:6bf0743ece18 284 // If not repeated start, send stop.
demayer 0:6bf0743ece18 285 if (stop) {
demayer 0:6bf0743ece18 286 i2c_stop(obj);
demayer 0:6bf0743ece18 287 }
demayer 0:6bf0743ece18 288
demayer 0:6bf0743ece18 289 return length;
demayer 0:6bf0743ece18 290 }
demayer 0:6bf0743ece18 291
demayer 0:6bf0743ece18 292 void i2c_reset(i2c_t *obj) {
demayer 0:6bf0743ece18 293 i2c_stop(obj);
demayer 0:6bf0743ece18 294 }
demayer 0:6bf0743ece18 295
demayer 0:6bf0743ece18 296 int i2c_byte_read(i2c_t *obj, int last) {
demayer 0:6bf0743ece18 297 return (i2c_do_read(obj, last) & 0xFF);
demayer 0:6bf0743ece18 298 }
demayer 0:6bf0743ece18 299
demayer 0:6bf0743ece18 300 int i2c_byte_write(i2c_t *obj, int data) {
demayer 0:6bf0743ece18 301 int ack;
demayer 0:6bf0743ece18 302 int status = i2c_do_write(obj, (data & 0xFF), 0);
demayer 0:6bf0743ece18 303
demayer 0:6bf0743ece18 304 switch(status) {
demayer 0:6bf0743ece18 305 case 0x18: case 0x28: // Master transmit ACKs
demayer 0:6bf0743ece18 306 ack = 1;
demayer 0:6bf0743ece18 307 break;
demayer 0:6bf0743ece18 308 case 0x40: // Master receive address transmitted ACK
demayer 0:6bf0743ece18 309 ack = 1;
demayer 0:6bf0743ece18 310 break;
demayer 0:6bf0743ece18 311 case 0xB8: // Slave transmit ACK
demayer 0:6bf0743ece18 312 ack = 1;
demayer 0:6bf0743ece18 313 break;
demayer 0:6bf0743ece18 314 default:
demayer 0:6bf0743ece18 315 ack = 0;
demayer 0:6bf0743ece18 316 break;
demayer 0:6bf0743ece18 317 }
demayer 0:6bf0743ece18 318
demayer 0:6bf0743ece18 319 return ack;
demayer 0:6bf0743ece18 320 }
demayer 0:6bf0743ece18 321
demayer 0:6bf0743ece18 322 void i2c_slave_mode(i2c_t *obj, int enable_slave) {
demayer 0:6bf0743ece18 323 if (enable_slave != 0) {
demayer 0:6bf0743ece18 324 i2c_conclr(obj, 1, 1, 1, 0);
demayer 0:6bf0743ece18 325 i2c_conset(obj, 0, 0, 0, 1);
demayer 0:6bf0743ece18 326 } else {
demayer 0:6bf0743ece18 327 i2c_conclr(obj, 1, 1, 1, 1);
demayer 0:6bf0743ece18 328 }
demayer 0:6bf0743ece18 329 }
demayer 0:6bf0743ece18 330
demayer 0:6bf0743ece18 331 int i2c_slave_receive(i2c_t *obj) {
demayer 0:6bf0743ece18 332 int status;
demayer 0:6bf0743ece18 333 int retval;
demayer 0:6bf0743ece18 334
demayer 0:6bf0743ece18 335 status = i2c_status(obj);
demayer 0:6bf0743ece18 336 switch(status) {
demayer 0:6bf0743ece18 337 case 0x60: retval = 3; break;
demayer 0:6bf0743ece18 338 case 0x70: retval = 2; break;
demayer 0:6bf0743ece18 339 case 0xA8: retval = 1; break;
demayer 0:6bf0743ece18 340 default : retval = 0; break;
demayer 0:6bf0743ece18 341 }
demayer 0:6bf0743ece18 342
demayer 0:6bf0743ece18 343 return(retval);
demayer 0:6bf0743ece18 344 }
demayer 0:6bf0743ece18 345
demayer 0:6bf0743ece18 346 int i2c_slave_read(i2c_t *obj, char *data, int length) {
demayer 0:6bf0743ece18 347 int count = 0;
demayer 0:6bf0743ece18 348 int status;
demayer 0:6bf0743ece18 349
demayer 0:6bf0743ece18 350 do {
demayer 0:6bf0743ece18 351 i2c_clear_SI(obj);
demayer 0:6bf0743ece18 352 i2c_wait_SI(obj);
demayer 0:6bf0743ece18 353 status = i2c_status(obj);
demayer 0:6bf0743ece18 354 if((status == 0x80) || (status == 0x90)) {
demayer 0:6bf0743ece18 355 data[count] = I2C_DAT(obj) & 0xFF;
demayer 0:6bf0743ece18 356 }
demayer 0:6bf0743ece18 357 count++;
demayer 0:6bf0743ece18 358 } while (((status == 0x80) || (status == 0x90) ||
demayer 0:6bf0743ece18 359 (status == 0x060) || (status == 0x70)) && (count < length));
demayer 0:6bf0743ece18 360
demayer 0:6bf0743ece18 361 if(status != 0xA0) {
demayer 0:6bf0743ece18 362 i2c_stop(obj);
demayer 0:6bf0743ece18 363 }
demayer 0:6bf0743ece18 364
demayer 0:6bf0743ece18 365 i2c_clear_SI(obj);
demayer 0:6bf0743ece18 366
demayer 0:6bf0743ece18 367 return count;
demayer 0:6bf0743ece18 368 }
demayer 0:6bf0743ece18 369
demayer 0:6bf0743ece18 370 int i2c_slave_write(i2c_t *obj, const char *data, int length) {
demayer 0:6bf0743ece18 371 int count = 0;
demayer 0:6bf0743ece18 372 int status;
demayer 0:6bf0743ece18 373
demayer 0:6bf0743ece18 374 if(length <= 0) {
demayer 0:6bf0743ece18 375 return(0);
demayer 0:6bf0743ece18 376 }
demayer 0:6bf0743ece18 377
demayer 0:6bf0743ece18 378 do {
demayer 0:6bf0743ece18 379 status = i2c_do_write(obj, data[count], 0);
demayer 0:6bf0743ece18 380 count++;
demayer 0:6bf0743ece18 381 } while ((count < length) && (status == 0xB8));
demayer 0:6bf0743ece18 382
demayer 0:6bf0743ece18 383 if ((status != 0xC0) && (status != 0xC8)) {
demayer 0:6bf0743ece18 384 i2c_stop(obj);
demayer 0:6bf0743ece18 385 }
demayer 0:6bf0743ece18 386
demayer 0:6bf0743ece18 387 i2c_clear_SI(obj);
demayer 0:6bf0743ece18 388
demayer 0:6bf0743ece18 389 return(count);
demayer 0:6bf0743ece18 390 }
demayer 0:6bf0743ece18 391
demayer 0:6bf0743ece18 392 void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask) {
demayer 0:6bf0743ece18 393 uint32_t addr;
demayer 0:6bf0743ece18 394
demayer 0:6bf0743ece18 395 if ((idx >= 0) && (idx <= 3)) {
demayer 0:6bf0743ece18 396 addr = ((uint32_t)obj->i2c) + I2C_addr_offset[0][idx];
demayer 0:6bf0743ece18 397 *((uint32_t *) addr) = address & 0xFF;
demayer 0:6bf0743ece18 398 addr = ((uint32_t)obj->i2c) + I2C_addr_offset[1][idx];
demayer 0:6bf0743ece18 399 *((uint32_t *) addr) = mask & 0xFE;
demayer 0:6bf0743ece18 400 }
demayer 0:6bf0743ece18 401 }