EL4121 Embedded System / mbed-os

Dependents:   cobaLCDJoyMotor_Thread odometry_omni_3roda_v3 odometry_omni_3roda_v1 odometry_omni_3roda_v2 ... more

targets/TARGET_NXP/TARGET_LPC13XX/i2c_api.c@0:b74591d5ab33, 2017-12-11 (annotated)

Committer:
be_bryan
Date:
Mon Dec 11 17:54:04 2017 +0000
Revision:
0:b74591d5ab33
motor ++

Who changed what in which revision?

UserRevisionLine numberNew contents of line
be_bryan 0:b74591d5ab33 1 /* mbed Microcontroller Library
be_bryan 0:b74591d5ab33 2 * Copyright (c) 2006-2013 ARM Limited
be_bryan 0:b74591d5ab33 3 *
be_bryan 0:b74591d5ab33 4 * Licensed under the Apache License, Version 2.0 (the "License");
be_bryan 0:b74591d5ab33 5 * you may not use this file except in compliance with the License.
be_bryan 0:b74591d5ab33 6 * You may obtain a copy of the License at
be_bryan 0:b74591d5ab33 7 *
be_bryan 0:b74591d5ab33 8 * http://www.apache.org/licenses/LICENSE-2.0
be_bryan 0:b74591d5ab33 9 *
be_bryan 0:b74591d5ab33 10 * Unless required by applicable law or agreed to in writing, software
be_bryan 0:b74591d5ab33 11 * distributed under the License is distributed on an "AS IS" BASIS,
be_bryan 0:b74591d5ab33 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
be_bryan 0:b74591d5ab33 13 * See the License for the specific language governing permissions and
be_bryan 0:b74591d5ab33 14 * limitations under the License.
be_bryan 0:b74591d5ab33 15 */
be_bryan 0:b74591d5ab33 16 #include "mbed_assert.h"
be_bryan 0:b74591d5ab33 17 #include "i2c_api.h"
be_bryan 0:b74591d5ab33 18 #include "cmsis.h"
be_bryan 0:b74591d5ab33 19 #include "pinmap.h"
be_bryan 0:b74591d5ab33 20 #include "mbed_error.h"
be_bryan 0:b74591d5ab33 21
be_bryan 0:b74591d5ab33 22 static const PinMap PinMap_I2C_SDA[] = {
be_bryan 0:b74591d5ab33 23 {P0_5, I2C_0, 1},
be_bryan 0:b74591d5ab33 24 {NC , NC , 0}
be_bryan 0:b74591d5ab33 25 };
be_bryan 0:b74591d5ab33 26
be_bryan 0:b74591d5ab33 27 static const PinMap PinMap_I2C_SCL[] = {
be_bryan 0:b74591d5ab33 28 {P0_4, I2C_0, 1},
be_bryan 0:b74591d5ab33 29 {NC , NC, 0}
be_bryan 0:b74591d5ab33 30 };
be_bryan 0:b74591d5ab33 31
be_bryan 0:b74591d5ab33 32 #define I2C_CONSET(x) (x->i2c->CONSET)
be_bryan 0:b74591d5ab33 33 #define I2C_CONCLR(x) (x->i2c->CONCLR)
be_bryan 0:b74591d5ab33 34 #define I2C_STAT(x) (x->i2c->STAT)
be_bryan 0:b74591d5ab33 35 #define I2C_DAT(x) (x->i2c->DAT)
be_bryan 0:b74591d5ab33 36 #define I2C_SCLL(x, val) (x->i2c->SCLL = val)
be_bryan 0:b74591d5ab33 37 #define I2C_SCLH(x, val) (x->i2c->SCLH = val)
be_bryan 0:b74591d5ab33 38
be_bryan 0:b74591d5ab33 39 static const uint32_t I2C_addr_offset[2][4] = {
be_bryan 0:b74591d5ab33 40 {0x0C, 0x20, 0x24, 0x28},
be_bryan 0:b74591d5ab33 41 {0x30, 0x34, 0x38, 0x3C}
be_bryan 0:b74591d5ab33 42 };
be_bryan 0:b74591d5ab33 43
be_bryan 0:b74591d5ab33 44 static inline void i2c_conclr(i2c_t *obj, int start, int stop, int interrupt, int acknowledge) {
be_bryan 0:b74591d5ab33 45 I2C_CONCLR(obj) = (start << 5)
be_bryan 0:b74591d5ab33 46 | (stop << 4)
be_bryan 0:b74591d5ab33 47 | (interrupt << 3)
be_bryan 0:b74591d5ab33 48 | (acknowledge << 2);
be_bryan 0:b74591d5ab33 49 }
be_bryan 0:b74591d5ab33 50
be_bryan 0:b74591d5ab33 51 static inline void i2c_conset(i2c_t *obj, int start, int stop, int interrupt, int acknowledge) {
be_bryan 0:b74591d5ab33 52 I2C_CONSET(obj) = (start << 5)
be_bryan 0:b74591d5ab33 53 | (stop << 4)
be_bryan 0:b74591d5ab33 54 | (interrupt << 3)
be_bryan 0:b74591d5ab33 55 | (acknowledge << 2);
be_bryan 0:b74591d5ab33 56 }
be_bryan 0:b74591d5ab33 57
be_bryan 0:b74591d5ab33 58 // Clear the Serial Interrupt (SI)
be_bryan 0:b74591d5ab33 59 static inline void i2c_clear_SI(i2c_t *obj) {
be_bryan 0:b74591d5ab33 60 i2c_conclr(obj, 0, 0, 1, 0);
be_bryan 0:b74591d5ab33 61 }
be_bryan 0:b74591d5ab33 62
be_bryan 0:b74591d5ab33 63 static inline int i2c_status(i2c_t *obj) {
be_bryan 0:b74591d5ab33 64 return I2C_STAT(obj);
be_bryan 0:b74591d5ab33 65 }
be_bryan 0:b74591d5ab33 66
be_bryan 0:b74591d5ab33 67 // Wait until the Serial Interrupt (SI) is set
be_bryan 0:b74591d5ab33 68 static int i2c_wait_SI(i2c_t *obj) {
be_bryan 0:b74591d5ab33 69 int timeout = 0;
be_bryan 0:b74591d5ab33 70 while (!(I2C_CONSET(obj) & (1 << 3))) {
be_bryan 0:b74591d5ab33 71 timeout++;
be_bryan 0:b74591d5ab33 72 if (timeout > 100000) return -1;
be_bryan 0:b74591d5ab33 73 }
be_bryan 0:b74591d5ab33 74 return 0;
be_bryan 0:b74591d5ab33 75 }
be_bryan 0:b74591d5ab33 76
be_bryan 0:b74591d5ab33 77 static inline void i2c_interface_enable(i2c_t *obj) {
be_bryan 0:b74591d5ab33 78 I2C_CONSET(obj) = 0x40;
be_bryan 0:b74591d5ab33 79 }
be_bryan 0:b74591d5ab33 80
be_bryan 0:b74591d5ab33 81 static inline void i2c_power_enable(i2c_t *obj) {
be_bryan 0:b74591d5ab33 82 LPC_SYSCON->SYSAHBCLKCTRL |= (1 << 5);
be_bryan 0:b74591d5ab33 83 LPC_SYSCON->PRESETCTRL |= 1 << 1;
be_bryan 0:b74591d5ab33 84 }
be_bryan 0:b74591d5ab33 85
be_bryan 0:b74591d5ab33 86 void i2c_init(i2c_t *obj, PinName sda, PinName scl) {
be_bryan 0:b74591d5ab33 87 // determine the SPI to use
be_bryan 0:b74591d5ab33 88 I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA);
be_bryan 0:b74591d5ab33 89 I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL);
be_bryan 0:b74591d5ab33 90 obj->i2c = (LPC_I2C_Type *)pinmap_merge(i2c_sda, i2c_scl);
be_bryan 0:b74591d5ab33 91 MBED_ASSERT((int)obj->i2c != NC);
be_bryan 0:b74591d5ab33 92
be_bryan 0:b74591d5ab33 93 // enable power
be_bryan 0:b74591d5ab33 94 i2c_power_enable(obj);
be_bryan 0:b74591d5ab33 95
be_bryan 0:b74591d5ab33 96 // set default frequency at 100k
be_bryan 0:b74591d5ab33 97 i2c_frequency(obj, 100000);
be_bryan 0:b74591d5ab33 98 i2c_conclr(obj, 1, 1, 1, 1);
be_bryan 0:b74591d5ab33 99 i2c_interface_enable(obj);
be_bryan 0:b74591d5ab33 100
be_bryan 0:b74591d5ab33 101 pinmap_pinout(sda, PinMap_I2C_SDA);
be_bryan 0:b74591d5ab33 102 pinmap_pinout(scl, PinMap_I2C_SCL);
be_bryan 0:b74591d5ab33 103 }
be_bryan 0:b74591d5ab33 104
be_bryan 0:b74591d5ab33 105 inline int i2c_start(i2c_t *obj) {
be_bryan 0:b74591d5ab33 106 int status = 0;
be_bryan 0:b74591d5ab33 107 int isInterrupted = I2C_CONSET(obj) & (1 << 3);
be_bryan 0:b74591d5ab33 108
be_bryan 0:b74591d5ab33 109 // 8.1 Before master mode can be entered, I2CON must be initialised to:
be_bryan 0:b74591d5ab33 110 // - I2EN STA STO SI AA - -
be_bryan 0:b74591d5ab33 111 // - 1 0 0 x x - -
be_bryan 0:b74591d5ab33 112 // if AA = 0, it can't enter slave mode
be_bryan 0:b74591d5ab33 113 i2c_conclr(obj, 1, 1, 0, 1);
be_bryan 0:b74591d5ab33 114
be_bryan 0:b74591d5ab33 115 // The master mode may now be entered by setting the STA bit
be_bryan 0:b74591d5ab33 116 // this will generate a start condition when the bus becomes free
be_bryan 0:b74591d5ab33 117 i2c_conset(obj, 1, 0, 0, 1);
be_bryan 0:b74591d5ab33 118 // Clearing SI bit when it wasn't set on entry can jump past state
be_bryan 0:b74591d5ab33 119 // 0x10 or 0x08 and erroneously send uninitialized slave address.
be_bryan 0:b74591d5ab33 120 if (isInterrupted)
be_bryan 0:b74591d5ab33 121 i2c_clear_SI(obj);
be_bryan 0:b74591d5ab33 122
be_bryan 0:b74591d5ab33 123 i2c_wait_SI(obj);
be_bryan 0:b74591d5ab33 124 status = i2c_status(obj);
be_bryan 0:b74591d5ab33 125
be_bryan 0:b74591d5ab33 126 // Clear start bit now that it's transmitted
be_bryan 0:b74591d5ab33 127 i2c_conclr(obj, 1, 0, 0, 0);
be_bryan 0:b74591d5ab33 128 return status;
be_bryan 0:b74591d5ab33 129 }
be_bryan 0:b74591d5ab33 130
be_bryan 0:b74591d5ab33 131 inline int i2c_stop(i2c_t *obj) {
be_bryan 0:b74591d5ab33 132 int timeout = 0;
be_bryan 0:b74591d5ab33 133
be_bryan 0:b74591d5ab33 134 // write the stop bit
be_bryan 0:b74591d5ab33 135 i2c_conset(obj, 0, 1, 0, 0);
be_bryan 0:b74591d5ab33 136 i2c_clear_SI(obj);
be_bryan 0:b74591d5ab33 137
be_bryan 0:b74591d5ab33 138 // wait for STO bit to reset
be_bryan 0:b74591d5ab33 139 while(I2C_CONSET(obj) & (1 << 4)) {
be_bryan 0:b74591d5ab33 140 timeout ++;
be_bryan 0:b74591d5ab33 141 if (timeout > 100000) return 1;
be_bryan 0:b74591d5ab33 142 }
be_bryan 0:b74591d5ab33 143
be_bryan 0:b74591d5ab33 144 return 0;
be_bryan 0:b74591d5ab33 145 }
be_bryan 0:b74591d5ab33 146
be_bryan 0:b74591d5ab33 147
be_bryan 0:b74591d5ab33 148 static inline int i2c_do_write(i2c_t *obj, int value, uint8_t addr) {
be_bryan 0:b74591d5ab33 149 // write the data
be_bryan 0:b74591d5ab33 150 I2C_DAT(obj) = value;
be_bryan 0:b74591d5ab33 151
be_bryan 0:b74591d5ab33 152 // clear SI to init a send
be_bryan 0:b74591d5ab33 153 i2c_clear_SI(obj);
be_bryan 0:b74591d5ab33 154
be_bryan 0:b74591d5ab33 155 // wait and return status
be_bryan 0:b74591d5ab33 156 i2c_wait_SI(obj);
be_bryan 0:b74591d5ab33 157 return i2c_status(obj);
be_bryan 0:b74591d5ab33 158 }
be_bryan 0:b74591d5ab33 159
be_bryan 0:b74591d5ab33 160 static inline int i2c_do_read(i2c_t *obj, int last) {
be_bryan 0:b74591d5ab33 161 // we are in state 0x40 (SLA+R tx'd) or 0x50 (data rx'd and ack)
be_bryan 0:b74591d5ab33 162 if (last) {
be_bryan 0:b74591d5ab33 163 i2c_conclr(obj, 0, 0, 0, 1); // send a NOT ACK
be_bryan 0:b74591d5ab33 164 } else {
be_bryan 0:b74591d5ab33 165 i2c_conset(obj, 0, 0, 0, 1); // send a ACK
be_bryan 0:b74591d5ab33 166 }
be_bryan 0:b74591d5ab33 167
be_bryan 0:b74591d5ab33 168 // accept byte
be_bryan 0:b74591d5ab33 169 i2c_clear_SI(obj);
be_bryan 0:b74591d5ab33 170
be_bryan 0:b74591d5ab33 171 // wait for it to arrive
be_bryan 0:b74591d5ab33 172 i2c_wait_SI(obj);
be_bryan 0:b74591d5ab33 173
be_bryan 0:b74591d5ab33 174 // return the data
be_bryan 0:b74591d5ab33 175 return (I2C_DAT(obj) & 0xFF);
be_bryan 0:b74591d5ab33 176 }
be_bryan 0:b74591d5ab33 177
be_bryan 0:b74591d5ab33 178 void i2c_frequency(i2c_t *obj, int hz) {
be_bryan 0:b74591d5ab33 179 // No peripheral clock divider on the M0
be_bryan 0:b74591d5ab33 180 uint32_t PCLK = SystemCoreClock;
be_bryan 0:b74591d5ab33 181
be_bryan 0:b74591d5ab33 182 uint32_t pulse = PCLK / (hz * 2);
be_bryan 0:b74591d5ab33 183
be_bryan 0:b74591d5ab33 184 // I2C Rate
be_bryan 0:b74591d5ab33 185 I2C_SCLL(obj, pulse);
be_bryan 0:b74591d5ab33 186 I2C_SCLH(obj, pulse);
be_bryan 0:b74591d5ab33 187 }
be_bryan 0:b74591d5ab33 188
be_bryan 0:b74591d5ab33 189 // The I2C does a read or a write as a whole operation
be_bryan 0:b74591d5ab33 190 // There are two types of error conditions it can encounter
be_bryan 0:b74591d5ab33 191 // 1) it can not obtain the bus
be_bryan 0:b74591d5ab33 192 // 2) it gets error responses at part of the transmission
be_bryan 0:b74591d5ab33 193 //
be_bryan 0:b74591d5ab33 194 // We tackle them as follows:
be_bryan 0:b74591d5ab33 195 // 1) we retry until we get the bus. we could have a "timeout" if we can not get it
be_bryan 0:b74591d5ab33 196 // which basically turns it in to a 2)
be_bryan 0:b74591d5ab33 197 // 2) on error, we use the standard error mechanisms to report/debug
be_bryan 0:b74591d5ab33 198 //
be_bryan 0:b74591d5ab33 199 // Therefore an I2C transaction should always complete. If it doesn't it is usually
be_bryan 0:b74591d5ab33 200 // because something is setup wrong (e.g. wiring), and we don't need to programatically
be_bryan 0:b74591d5ab33 201 // check for that
be_bryan 0:b74591d5ab33 202
be_bryan 0:b74591d5ab33 203 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) {
be_bryan 0:b74591d5ab33 204 int count, status;
be_bryan 0:b74591d5ab33 205
be_bryan 0:b74591d5ab33 206 status = i2c_start(obj);
be_bryan 0:b74591d5ab33 207
be_bryan 0:b74591d5ab33 208 if ((status != 0x10) && (status != 0x08)) {
be_bryan 0:b74591d5ab33 209 i2c_stop(obj);
be_bryan 0:b74591d5ab33 210 return I2C_ERROR_BUS_BUSY;
be_bryan 0:b74591d5ab33 211 }
be_bryan 0:b74591d5ab33 212
be_bryan 0:b74591d5ab33 213 status = i2c_do_write(obj, (address | 0x01), 1);
be_bryan 0:b74591d5ab33 214 if (status != 0x40) {
be_bryan 0:b74591d5ab33 215 i2c_stop(obj);
be_bryan 0:b74591d5ab33 216 return I2C_ERROR_NO_SLAVE;
be_bryan 0:b74591d5ab33 217 }
be_bryan 0:b74591d5ab33 218
be_bryan 0:b74591d5ab33 219 // Read in all except last byte
be_bryan 0:b74591d5ab33 220 for (count = 0; count < (length - 1); count++) {
be_bryan 0:b74591d5ab33 221 int value = i2c_do_read(obj, 0);
be_bryan 0:b74591d5ab33 222 status = i2c_status(obj);
be_bryan 0:b74591d5ab33 223 if (status != 0x50) {
be_bryan 0:b74591d5ab33 224 i2c_stop(obj);
be_bryan 0:b74591d5ab33 225 return count;
be_bryan 0:b74591d5ab33 226 }
be_bryan 0:b74591d5ab33 227 data[count] = (char) value;
be_bryan 0:b74591d5ab33 228 }
be_bryan 0:b74591d5ab33 229
be_bryan 0:b74591d5ab33 230 // read in last byte
be_bryan 0:b74591d5ab33 231 int value = i2c_do_read(obj, 1);
be_bryan 0:b74591d5ab33 232 status = i2c_status(obj);
be_bryan 0:b74591d5ab33 233 if (status != 0x58) {
be_bryan 0:b74591d5ab33 234 i2c_stop(obj);
be_bryan 0:b74591d5ab33 235 return length - 1;
be_bryan 0:b74591d5ab33 236 }
be_bryan 0:b74591d5ab33 237
be_bryan 0:b74591d5ab33 238 data[count] = (char) value;
be_bryan 0:b74591d5ab33 239
be_bryan 0:b74591d5ab33 240 // If not repeated start, send stop.
be_bryan 0:b74591d5ab33 241 if (stop) {
be_bryan 0:b74591d5ab33 242 i2c_stop(obj);
be_bryan 0:b74591d5ab33 243 }
be_bryan 0:b74591d5ab33 244
be_bryan 0:b74591d5ab33 245 return length;
be_bryan 0:b74591d5ab33 246 }
be_bryan 0:b74591d5ab33 247
be_bryan 0:b74591d5ab33 248 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) {
be_bryan 0:b74591d5ab33 249 int i, status;
be_bryan 0:b74591d5ab33 250
be_bryan 0:b74591d5ab33 251 status = i2c_start(obj);
be_bryan 0:b74591d5ab33 252
be_bryan 0:b74591d5ab33 253 if ((status != 0x10) && (status != 0x08)) {
be_bryan 0:b74591d5ab33 254 i2c_stop(obj);
be_bryan 0:b74591d5ab33 255 return I2C_ERROR_BUS_BUSY;
be_bryan 0:b74591d5ab33 256 }
be_bryan 0:b74591d5ab33 257
be_bryan 0:b74591d5ab33 258 status = i2c_do_write(obj, (address & 0xFE), 1);
be_bryan 0:b74591d5ab33 259 if (status != 0x18) {
be_bryan 0:b74591d5ab33 260 i2c_stop(obj);
be_bryan 0:b74591d5ab33 261 return I2C_ERROR_NO_SLAVE;
be_bryan 0:b74591d5ab33 262 }
be_bryan 0:b74591d5ab33 263
be_bryan 0:b74591d5ab33 264 for (i=0; i<length; i++) {
be_bryan 0:b74591d5ab33 265 status = i2c_do_write(obj, data[i], 0);
be_bryan 0:b74591d5ab33 266 if(status != 0x28) {
be_bryan 0:b74591d5ab33 267 i2c_stop(obj);
be_bryan 0:b74591d5ab33 268 return i;
be_bryan 0:b74591d5ab33 269 }
be_bryan 0:b74591d5ab33 270 }
be_bryan 0:b74591d5ab33 271
be_bryan 0:b74591d5ab33 272 // clearing the serial interrupt here might cause an unintended rewrite of the last byte
be_bryan 0:b74591d5ab33 273 // see also issue report https://mbed.org/users/mbed_official/code/mbed/issues/1
be_bryan 0:b74591d5ab33 274 // i2c_clear_SI(obj);
be_bryan 0:b74591d5ab33 275
be_bryan 0:b74591d5ab33 276 // If not repeated start, send stop.
be_bryan 0:b74591d5ab33 277 if (stop) {
be_bryan 0:b74591d5ab33 278 i2c_stop(obj);
be_bryan 0:b74591d5ab33 279 }
be_bryan 0:b74591d5ab33 280
be_bryan 0:b74591d5ab33 281 return length;
be_bryan 0:b74591d5ab33 282 }
be_bryan 0:b74591d5ab33 283
be_bryan 0:b74591d5ab33 284 void i2c_reset(i2c_t *obj) {
be_bryan 0:b74591d5ab33 285 i2c_stop(obj);
be_bryan 0:b74591d5ab33 286 }
be_bryan 0:b74591d5ab33 287
be_bryan 0:b74591d5ab33 288 int i2c_byte_read(i2c_t *obj, int last) {
be_bryan 0:b74591d5ab33 289 return (i2c_do_read(obj, last) & 0xFF);
be_bryan 0:b74591d5ab33 290 }
be_bryan 0:b74591d5ab33 291
be_bryan 0:b74591d5ab33 292 int i2c_byte_write(i2c_t *obj, int data) {
be_bryan 0:b74591d5ab33 293 int ack;
be_bryan 0:b74591d5ab33 294 int status = i2c_do_write(obj, (data & 0xFF), 0);
be_bryan 0:b74591d5ab33 295
be_bryan 0:b74591d5ab33 296 switch(status) {
be_bryan 0:b74591d5ab33 297 case 0x18: case 0x28: // Master transmit ACKs
be_bryan 0:b74591d5ab33 298 ack = 1;
be_bryan 0:b74591d5ab33 299 break;
be_bryan 0:b74591d5ab33 300 case 0x40: // Master receive address transmitted ACK
be_bryan 0:b74591d5ab33 301 ack = 1;
be_bryan 0:b74591d5ab33 302 break;
be_bryan 0:b74591d5ab33 303 case 0xB8: // Slave transmit ACK
be_bryan 0:b74591d5ab33 304 ack = 1;
be_bryan 0:b74591d5ab33 305 break;
be_bryan 0:b74591d5ab33 306 default:
be_bryan 0:b74591d5ab33 307 ack = 0;
be_bryan 0:b74591d5ab33 308 break;
be_bryan 0:b74591d5ab33 309 }
be_bryan 0:b74591d5ab33 310
be_bryan 0:b74591d5ab33 311 return ack;
be_bryan 0:b74591d5ab33 312 }
be_bryan 0:b74591d5ab33 313
be_bryan 0:b74591d5ab33 314 void i2c_slave_mode(i2c_t *obj, int enable_slave) {
be_bryan 0:b74591d5ab33 315 if (enable_slave != 0) {
be_bryan 0:b74591d5ab33 316 i2c_conclr(obj, 1, 1, 1, 0);
be_bryan 0:b74591d5ab33 317 i2c_conset(obj, 0, 0, 0, 1);
be_bryan 0:b74591d5ab33 318 } else {
be_bryan 0:b74591d5ab33 319 i2c_conclr(obj, 1, 1, 1, 1);
be_bryan 0:b74591d5ab33 320 }
be_bryan 0:b74591d5ab33 321 }
be_bryan 0:b74591d5ab33 322
be_bryan 0:b74591d5ab33 323 int i2c_slave_receive(i2c_t *obj) {
be_bryan 0:b74591d5ab33 324 int status;
be_bryan 0:b74591d5ab33 325 int retval;
be_bryan 0:b74591d5ab33 326
be_bryan 0:b74591d5ab33 327 status = i2c_status(obj);
be_bryan 0:b74591d5ab33 328 switch(status) {
be_bryan 0:b74591d5ab33 329 case 0x60: retval = 3; break;
be_bryan 0:b74591d5ab33 330 case 0x70: retval = 2; break;
be_bryan 0:b74591d5ab33 331 case 0xA8: retval = 1; break;
be_bryan 0:b74591d5ab33 332 default : retval = 0; break;
be_bryan 0:b74591d5ab33 333 }
be_bryan 0:b74591d5ab33 334
be_bryan 0:b74591d5ab33 335 return(retval);
be_bryan 0:b74591d5ab33 336 }
be_bryan 0:b74591d5ab33 337
be_bryan 0:b74591d5ab33 338 int i2c_slave_read(i2c_t *obj, char *data, int length) {
be_bryan 0:b74591d5ab33 339 int count = 0;
be_bryan 0:b74591d5ab33 340 int status;
be_bryan 0:b74591d5ab33 341
be_bryan 0:b74591d5ab33 342 do {
be_bryan 0:b74591d5ab33 343 i2c_clear_SI(obj);
be_bryan 0:b74591d5ab33 344 i2c_wait_SI(obj);
be_bryan 0:b74591d5ab33 345 status = i2c_status(obj);
be_bryan 0:b74591d5ab33 346 if((status == 0x80) || (status == 0x90)) {
be_bryan 0:b74591d5ab33 347 data[count] = I2C_DAT(obj) & 0xFF;
be_bryan 0:b74591d5ab33 348 }
be_bryan 0:b74591d5ab33 349 count++;
be_bryan 0:b74591d5ab33 350 } while (((status == 0x80) || (status == 0x90) ||
be_bryan 0:b74591d5ab33 351 (status == 0x060) || (status == 0x70)) && (count < length));
be_bryan 0:b74591d5ab33 352
be_bryan 0:b74591d5ab33 353 if(status != 0xA0) {
be_bryan 0:b74591d5ab33 354 i2c_stop(obj);
be_bryan 0:b74591d5ab33 355 }
be_bryan 0:b74591d5ab33 356
be_bryan 0:b74591d5ab33 357 i2c_clear_SI(obj);
be_bryan 0:b74591d5ab33 358
be_bryan 0:b74591d5ab33 359 return count;
be_bryan 0:b74591d5ab33 360 }
be_bryan 0:b74591d5ab33 361
be_bryan 0:b74591d5ab33 362 int i2c_slave_write(i2c_t *obj, const char *data, int length) {
be_bryan 0:b74591d5ab33 363 int count = 0;
be_bryan 0:b74591d5ab33 364 int status;
be_bryan 0:b74591d5ab33 365
be_bryan 0:b74591d5ab33 366 if(length <= 0) {
be_bryan 0:b74591d5ab33 367 return(0);
be_bryan 0:b74591d5ab33 368 }
be_bryan 0:b74591d5ab33 369
be_bryan 0:b74591d5ab33 370 do {
be_bryan 0:b74591d5ab33 371 status = i2c_do_write(obj, data[count], 0);
be_bryan 0:b74591d5ab33 372 count++;
be_bryan 0:b74591d5ab33 373 } while ((count < length) && (status == 0xB8));
be_bryan 0:b74591d5ab33 374
be_bryan 0:b74591d5ab33 375 if((status != 0xC0) && (status != 0xC8)) {
be_bryan 0:b74591d5ab33 376 i2c_stop(obj);
be_bryan 0:b74591d5ab33 377 }
be_bryan 0:b74591d5ab33 378
be_bryan 0:b74591d5ab33 379 i2c_clear_SI(obj);
be_bryan 0:b74591d5ab33 380
be_bryan 0:b74591d5ab33 381 return(count);
be_bryan 0:b74591d5ab33 382 }
be_bryan 0:b74591d5ab33 383
be_bryan 0:b74591d5ab33 384 void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask) {
be_bryan 0:b74591d5ab33 385 uint32_t addr;
be_bryan 0:b74591d5ab33 386
be_bryan 0:b74591d5ab33 387 if ((idx >= 0) && (idx <= 3)) {
be_bryan 0:b74591d5ab33 388 addr = ((uint32_t)obj->i2c) + I2C_addr_offset[0][idx];
be_bryan 0:b74591d5ab33 389 *((uint32_t *) addr) = address & 0xFF;
be_bryan 0:b74591d5ab33 390 }
be_bryan 0:b74591d5ab33 391 }