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mbed library sources

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Superseded

This library was superseded by mbed-dev - https://os.mbed.com/users/mbed_official/code/mbed-dev/.

Development branch of the mbed library sources. This library is kept in synch with the latest changes from the mbed SDK and it is not guaranteed to work.

If you are looking for a stable and tested release, please import one of the official mbed library releases:

Import librarymbed

The official Mbed 2 C/C++ SDK provides the software platform and libraries to build your applications.

Last commit 20 Feb 2019 by mbed official

targets/hal/TARGET_Freescale/TARGET_KLXX/i2c_api.c@111:ae4891ca7084, 2014-03-06 (annotated)

Committer:
mbed_official
Date:
Thu Mar 06 10:00:06 2014 +0000
Revision:
111:ae4891ca7084
Parent:
82:0b31dbcd4769
Child:
178:a873352662d8
Synchronized with git revision 955bd9a5c9e042f1cf30bbae2a99afaab8eb4cbf



Full URL: https://github.com/mbedmicro/mbed/commit/955bd9a5c9e042f1cf30bbae2a99afaab8eb4cbf/

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 82:0b31dbcd4769 1 /* mbed Microcontroller Library
mbed_official 82:0b31dbcd4769 2 * Copyright (c) 2006-2013 ARM Limited
mbed_official 82:0b31dbcd4769 3 *
mbed_official 82:0b31dbcd4769 4 * Licensed under the Apache License, Version 2.0 (the "License");
mbed_official 82:0b31dbcd4769 5 * you may not use this file except in compliance with the License.
mbed_official 82:0b31dbcd4769 6 * You may obtain a copy of the License at
mbed_official 82:0b31dbcd4769 7 *
mbed_official 82:0b31dbcd4769 8 * http://www.apache.org/licenses/LICENSE-2.0
mbed_official 82:0b31dbcd4769 9 *
mbed_official 82:0b31dbcd4769 10 * Unless required by applicable law or agreed to in writing, software
mbed_official 82:0b31dbcd4769 11 * distributed under the License is distributed on an "AS IS" BASIS,
mbed_official 82:0b31dbcd4769 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
mbed_official 82:0b31dbcd4769 13 * See the License for the specific language governing permissions and
mbed_official 82:0b31dbcd4769 14 * limitations under the License.
mbed_official 82:0b31dbcd4769 15 */
mbed_official 82:0b31dbcd4769 16 #include "i2c_api.h"
mbed_official 82:0b31dbcd4769 17
mbed_official 82:0b31dbcd4769 18 #include "cmsis.h"
mbed_official 82:0b31dbcd4769 19 #include "pinmap.h"
mbed_official 82:0b31dbcd4769 20 #include "error.h"
mbed_official 82:0b31dbcd4769 21 #include "clk_freqs.h"
mbed_official 82:0b31dbcd4769 22 #include "PeripheralPins.h"
mbed_official 82:0b31dbcd4769 23
mbed_official 82:0b31dbcd4769 24 static const uint16_t ICR[0x40] = {
mbed_official 82:0b31dbcd4769 25 20, 22, 24, 26, 28,
mbed_official 82:0b31dbcd4769 26 30, 34, 40, 28, 32,
mbed_official 82:0b31dbcd4769 27 36, 40, 44, 48, 56,
mbed_official 82:0b31dbcd4769 28 68, 48, 56, 64, 72,
mbed_official 82:0b31dbcd4769 29 80, 88, 104, 128, 80,
mbed_official 82:0b31dbcd4769 30 96, 112, 128, 144, 160,
mbed_official 82:0b31dbcd4769 31 192, 240, 160, 192, 224,
mbed_official 82:0b31dbcd4769 32 256, 288, 320, 384, 480,
mbed_official 82:0b31dbcd4769 33 320, 384, 448, 512, 576,
mbed_official 82:0b31dbcd4769 34 640, 768, 960, 640, 768,
mbed_official 82:0b31dbcd4769 35 896, 1024, 1152, 1280, 1536,
mbed_official 82:0b31dbcd4769 36 1920, 1280, 1536, 1792, 2048,
mbed_official 82:0b31dbcd4769 37 2304, 2560, 3072, 3840
mbed_official 82:0b31dbcd4769 38 };
mbed_official 82:0b31dbcd4769 39
mbed_official 82:0b31dbcd4769 40 static uint8_t first_read;
mbed_official 82:0b31dbcd4769 41
mbed_official 82:0b31dbcd4769 42
mbed_official 82:0b31dbcd4769 43 void i2c_init(i2c_t *obj, PinName sda, PinName scl) {
mbed_official 82:0b31dbcd4769 44 // determine the I2C to use
mbed_official 82:0b31dbcd4769 45 I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA);
mbed_official 82:0b31dbcd4769 46 I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL);
mbed_official 82:0b31dbcd4769 47 obj->i2c = (I2C_Type*)pinmap_merge(i2c_sda, i2c_scl);
mbed_official 82:0b31dbcd4769 48 if ((int)obj->i2c == NC) {
mbed_official 82:0b31dbcd4769 49 error("I2C pin mapping failed");
mbed_official 82:0b31dbcd4769 50 }
mbed_official 82:0b31dbcd4769 51
mbed_official 82:0b31dbcd4769 52 // enable power
mbed_official 82:0b31dbcd4769 53 switch ((int)obj->i2c) {
mbed_official 82:0b31dbcd4769 54 case I2C_0: SIM->SCGC5 |= 1 << 13; SIM->SCGC4 |= 1 << 6; break;
mbed_official 82:0b31dbcd4769 55 case I2C_1: SIM->SCGC5 |= 1 << 11; SIM->SCGC4 |= 1 << 7; break;
mbed_official 82:0b31dbcd4769 56 }
mbed_official 82:0b31dbcd4769 57
mbed_official 82:0b31dbcd4769 58 // set default frequency at 100k
mbed_official 82:0b31dbcd4769 59 i2c_frequency(obj, 100000);
mbed_official 82:0b31dbcd4769 60
mbed_official 82:0b31dbcd4769 61 // enable I2C interface
mbed_official 82:0b31dbcd4769 62 obj->i2c->C1 |= 0x80;
mbed_official 82:0b31dbcd4769 63
mbed_official 82:0b31dbcd4769 64 pinmap_pinout(sda, PinMap_I2C_SDA);
mbed_official 82:0b31dbcd4769 65 pinmap_pinout(scl, PinMap_I2C_SCL);
mbed_official 82:0b31dbcd4769 66
mbed_official 82:0b31dbcd4769 67 first_read = 1;
mbed_official 82:0b31dbcd4769 68 }
mbed_official 82:0b31dbcd4769 69
mbed_official 82:0b31dbcd4769 70 int i2c_start(i2c_t *obj) {
mbed_official 82:0b31dbcd4769 71 uint8_t temp;
mbed_official 82:0b31dbcd4769 72 volatile int i;
mbed_official 82:0b31dbcd4769 73 // if we are in the middle of a transaction
mbed_official 82:0b31dbcd4769 74 // activate the repeat_start flag
mbed_official 82:0b31dbcd4769 75 if (obj->i2c->S & I2C_S_BUSY_MASK) {
mbed_official 82:0b31dbcd4769 76 // KL25Z errata sheet: repeat start cannot be generated if the
mbed_official 82:0b31dbcd4769 77 // I2Cx_F[MULT] field is set to a non-zero value
mbed_official 82:0b31dbcd4769 78 temp = obj->i2c->F >> 6;
mbed_official 82:0b31dbcd4769 79 obj->i2c->F &= 0x3F;
mbed_official 82:0b31dbcd4769 80 obj->i2c->C1 |= 0x04;
mbed_official 82:0b31dbcd4769 81 for (i = 0; i < 100; i ++) __NOP();
mbed_official 82:0b31dbcd4769 82 obj->i2c->F |= temp << 6;
mbed_official 82:0b31dbcd4769 83 } else {
mbed_official 82:0b31dbcd4769 84 obj->i2c->C1 |= I2C_C1_MST_MASK;
mbed_official 82:0b31dbcd4769 85 obj->i2c->C1 |= I2C_C1_TX_MASK;
mbed_official 82:0b31dbcd4769 86 }
mbed_official 82:0b31dbcd4769 87 first_read = 1;
mbed_official 82:0b31dbcd4769 88 return 0;
mbed_official 82:0b31dbcd4769 89 }
mbed_official 82:0b31dbcd4769 90
mbed_official 82:0b31dbcd4769 91 int i2c_stop(i2c_t *obj) {
mbed_official 82:0b31dbcd4769 92 volatile uint32_t n = 0;
mbed_official 82:0b31dbcd4769 93 obj->i2c->C1 &= ~I2C_C1_MST_MASK;
mbed_official 82:0b31dbcd4769 94 obj->i2c->C1 &= ~I2C_C1_TX_MASK;
mbed_official 82:0b31dbcd4769 95
mbed_official 82:0b31dbcd4769 96 // It seems that there are timing problems
mbed_official 82:0b31dbcd4769 97 // when there is no waiting time after a STOP.
mbed_official 82:0b31dbcd4769 98 // This wait is also included on the samples
mbed_official 82:0b31dbcd4769 99 // code provided with the freedom board
mbed_official 82:0b31dbcd4769 100 for (n = 0; n < 100; n++) __NOP();
mbed_official 82:0b31dbcd4769 101 first_read = 1;
mbed_official 82:0b31dbcd4769 102 return 0;
mbed_official 82:0b31dbcd4769 103 }
mbed_official 82:0b31dbcd4769 104
mbed_official 82:0b31dbcd4769 105 static int timeout_status_poll(i2c_t *obj, uint32_t mask) {
mbed_official 82:0b31dbcd4769 106 uint32_t i, timeout = 1000;
mbed_official 82:0b31dbcd4769 107
mbed_official 82:0b31dbcd4769 108 for (i = 0; i < timeout; i++) {
mbed_official 82:0b31dbcd4769 109 if (obj->i2c->S & mask)
mbed_official 82:0b31dbcd4769 110 return 0;
mbed_official 82:0b31dbcd4769 111 }
mbed_official 82:0b31dbcd4769 112
mbed_official 82:0b31dbcd4769 113 return 1;
mbed_official 82:0b31dbcd4769 114 }
mbed_official 82:0b31dbcd4769 115
mbed_official 82:0b31dbcd4769 116 // this function waits the end of a tx transfer and return the status of the transaction:
mbed_official 82:0b31dbcd4769 117 // 0: OK ack received
mbed_official 82:0b31dbcd4769 118 // 1: OK ack not received
mbed_official 82:0b31dbcd4769 119 // 2: failure
mbed_official 82:0b31dbcd4769 120 static int i2c_wait_end_tx_transfer(i2c_t *obj) {
mbed_official 82:0b31dbcd4769 121
mbed_official 82:0b31dbcd4769 122 // wait for the interrupt flag
mbed_official 82:0b31dbcd4769 123 if (timeout_status_poll(obj, I2C_S_IICIF_MASK)) {
mbed_official 82:0b31dbcd4769 124 return 2;
mbed_official 82:0b31dbcd4769 125 }
mbed_official 82:0b31dbcd4769 126
mbed_official 82:0b31dbcd4769 127 obj->i2c->S |= I2C_S_IICIF_MASK;
mbed_official 82:0b31dbcd4769 128
mbed_official 82:0b31dbcd4769 129 // wait transfer complete
mbed_official 82:0b31dbcd4769 130 if (timeout_status_poll(obj, I2C_S_TCF_MASK)) {
mbed_official 82:0b31dbcd4769 131 return 2;
mbed_official 82:0b31dbcd4769 132 }
mbed_official 82:0b31dbcd4769 133
mbed_official 82:0b31dbcd4769 134 // check if we received the ACK or not
mbed_official 82:0b31dbcd4769 135 return obj->i2c->S & I2C_S_RXAK_MASK ? 1 : 0;
mbed_official 82:0b31dbcd4769 136 }
mbed_official 82:0b31dbcd4769 137
mbed_official 82:0b31dbcd4769 138 // this function waits the end of a rx transfer and return the status of the transaction:
mbed_official 82:0b31dbcd4769 139 // 0: OK
mbed_official 82:0b31dbcd4769 140 // 1: failure
mbed_official 82:0b31dbcd4769 141 static int i2c_wait_end_rx_transfer(i2c_t *obj) {
mbed_official 82:0b31dbcd4769 142 // wait for the end of the rx transfer
mbed_official 82:0b31dbcd4769 143 if (timeout_status_poll(obj, I2C_S_IICIF_MASK)) {
mbed_official 82:0b31dbcd4769 144 return 1;
mbed_official 82:0b31dbcd4769 145 }
mbed_official 82:0b31dbcd4769 146
mbed_official 82:0b31dbcd4769 147 obj->i2c->S |= I2C_S_IICIF_MASK;
mbed_official 82:0b31dbcd4769 148
mbed_official 82:0b31dbcd4769 149 return 0;
mbed_official 82:0b31dbcd4769 150 }
mbed_official 82:0b31dbcd4769 151
mbed_official 82:0b31dbcd4769 152 static void i2c_send_nack(i2c_t *obj) {
mbed_official 82:0b31dbcd4769 153 obj->i2c->C1 |= I2C_C1_TXAK_MASK; // NACK
mbed_official 82:0b31dbcd4769 154 }
mbed_official 82:0b31dbcd4769 155
mbed_official 82:0b31dbcd4769 156 static void i2c_send_ack(i2c_t *obj) {
mbed_official 82:0b31dbcd4769 157 obj->i2c->C1 &= ~I2C_C1_TXAK_MASK; // ACK
mbed_official 82:0b31dbcd4769 158 }
mbed_official 82:0b31dbcd4769 159
mbed_official 82:0b31dbcd4769 160 static int i2c_do_write(i2c_t *obj, int value) {
mbed_official 82:0b31dbcd4769 161 // write the data
mbed_official 82:0b31dbcd4769 162 obj->i2c->D = value;
mbed_official 82:0b31dbcd4769 163
mbed_official 82:0b31dbcd4769 164 // init and wait the end of the transfer
mbed_official 82:0b31dbcd4769 165 return i2c_wait_end_tx_transfer(obj);
mbed_official 82:0b31dbcd4769 166 }
mbed_official 82:0b31dbcd4769 167
mbed_official 82:0b31dbcd4769 168 static int i2c_do_read(i2c_t *obj, char * data, int last) {
mbed_official 82:0b31dbcd4769 169 if (last)
mbed_official 82:0b31dbcd4769 170 i2c_send_nack(obj);
mbed_official 82:0b31dbcd4769 171 else
mbed_official 82:0b31dbcd4769 172 i2c_send_ack(obj);
mbed_official 82:0b31dbcd4769 173
mbed_official 82:0b31dbcd4769 174 *data = (obj->i2c->D & 0xFF);
mbed_official 82:0b31dbcd4769 175
mbed_official 82:0b31dbcd4769 176 // start rx transfer and wait the end of the transfer
mbed_official 82:0b31dbcd4769 177 return i2c_wait_end_rx_transfer(obj);
mbed_official 82:0b31dbcd4769 178 }
mbed_official 82:0b31dbcd4769 179
mbed_official 82:0b31dbcd4769 180 void i2c_frequency(i2c_t *obj, int hz) {
mbed_official 82:0b31dbcd4769 181 uint8_t icr = 0;
mbed_official 82:0b31dbcd4769 182 uint8_t mult = 0;
mbed_official 82:0b31dbcd4769 183 uint32_t error = 0;
mbed_official 82:0b31dbcd4769 184 uint32_t p_error = 0xffffffff;
mbed_official 82:0b31dbcd4769 185 uint32_t ref = 0;
mbed_official 82:0b31dbcd4769 186 uint8_t i, j;
mbed_official 82:0b31dbcd4769 187 // bus clk
mbed_official 82:0b31dbcd4769 188 uint32_t PCLK = bus_frequency();
mbed_official 82:0b31dbcd4769 189 uint32_t pulse = PCLK / (hz * 2);
mbed_official 82:0b31dbcd4769 190
mbed_official 82:0b31dbcd4769 191 // we look for the values that minimize the error
mbed_official 82:0b31dbcd4769 192
mbed_official 82:0b31dbcd4769 193 // test all the MULT values
mbed_official 82:0b31dbcd4769 194 for (i = 1; i < 5; i*=2) {
mbed_official 82:0b31dbcd4769 195 for (j = 0; j < 0x40; j++) {
mbed_official 82:0b31dbcd4769 196 ref = PCLK / (i*ICR[j]);
mbed_official 82:0b31dbcd4769 197 if (ref > (uint32_t)hz)
mbed_official 82:0b31dbcd4769 198 continue;
mbed_official 82:0b31dbcd4769 199 error = hz - ref;
mbed_official 82:0b31dbcd4769 200 if (error < p_error) {
mbed_official 82:0b31dbcd4769 201 icr = j;
mbed_official 82:0b31dbcd4769 202 mult = i/2;
mbed_official 82:0b31dbcd4769 203 p_error = error;
mbed_official 82:0b31dbcd4769 204 }
mbed_official 82:0b31dbcd4769 205 }
mbed_official 82:0b31dbcd4769 206 }
mbed_official 82:0b31dbcd4769 207 pulse = icr | (mult << 6);
mbed_official 82:0b31dbcd4769 208
mbed_official 82:0b31dbcd4769 209 // I2C Rate
mbed_official 82:0b31dbcd4769 210 obj->i2c->F = pulse;
mbed_official 82:0b31dbcd4769 211 }
mbed_official 82:0b31dbcd4769 212
mbed_official 82:0b31dbcd4769 213 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) {
mbed_official 82:0b31dbcd4769 214 int count;
mbed_official 82:0b31dbcd4769 215 char dummy_read, *ptr;
mbed_official 82:0b31dbcd4769 216
mbed_official 82:0b31dbcd4769 217 if (i2c_start(obj)) {
mbed_official 82:0b31dbcd4769 218 i2c_stop(obj);
mbed_official 82:0b31dbcd4769 219 return I2C_ERROR_BUS_BUSY;
mbed_official 82:0b31dbcd4769 220 }
mbed_official 82:0b31dbcd4769 221
mbed_official 82:0b31dbcd4769 222 if (i2c_do_write(obj, (address | 0x01))) {
mbed_official 82:0b31dbcd4769 223 i2c_stop(obj);
mbed_official 82:0b31dbcd4769 224 return I2C_ERROR_NO_SLAVE;
mbed_official 82:0b31dbcd4769 225 }
mbed_official 82:0b31dbcd4769 226
mbed_official 82:0b31dbcd4769 227 // set rx mode
mbed_official 82:0b31dbcd4769 228 obj->i2c->C1 &= ~I2C_C1_TX_MASK;
mbed_official 82:0b31dbcd4769 229
mbed_official 82:0b31dbcd4769 230 // Read in bytes
mbed_official 82:0b31dbcd4769 231 for (count = 0; count < (length); count++) {
mbed_official 82:0b31dbcd4769 232 ptr = (count == 0) ? &dummy_read : &data[count - 1];
mbed_official 82:0b31dbcd4769 233 uint8_t stop_ = (count == (length - 1)) ? 1 : 0;
mbed_official 82:0b31dbcd4769 234 if (i2c_do_read(obj, ptr, stop_)) {
mbed_official 82:0b31dbcd4769 235 i2c_stop(obj);
mbed_official 82:0b31dbcd4769 236 return count;
mbed_official 82:0b31dbcd4769 237 }
mbed_official 82:0b31dbcd4769 238 }
mbed_official 82:0b31dbcd4769 239
mbed_official 82:0b31dbcd4769 240 // If not repeated start, send stop.
mbed_official 82:0b31dbcd4769 241 if (stop) {
mbed_official 82:0b31dbcd4769 242 i2c_stop(obj);
mbed_official 82:0b31dbcd4769 243 }
mbed_official 82:0b31dbcd4769 244
mbed_official 82:0b31dbcd4769 245 // last read
mbed_official 82:0b31dbcd4769 246 data[count-1] = obj->i2c->D;
mbed_official 82:0b31dbcd4769 247
mbed_official 82:0b31dbcd4769 248 return length;
mbed_official 82:0b31dbcd4769 249 }
mbed_official 82:0b31dbcd4769 250 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) {
mbed_official 82:0b31dbcd4769 251 int i;
mbed_official 82:0b31dbcd4769 252
mbed_official 82:0b31dbcd4769 253 if (i2c_start(obj)) {
mbed_official 82:0b31dbcd4769 254 i2c_stop(obj);
mbed_official 82:0b31dbcd4769 255 return I2C_ERROR_BUS_BUSY;
mbed_official 82:0b31dbcd4769 256 }
mbed_official 82:0b31dbcd4769 257
mbed_official 82:0b31dbcd4769 258 if (i2c_do_write(obj, (address & 0xFE))) {
mbed_official 82:0b31dbcd4769 259 i2c_stop(obj);
mbed_official 82:0b31dbcd4769 260 return I2C_ERROR_NO_SLAVE;
mbed_official 82:0b31dbcd4769 261 }
mbed_official 82:0b31dbcd4769 262
mbed_official 82:0b31dbcd4769 263 for (i = 0; i < length; i++) {
mbed_official 82:0b31dbcd4769 264 if(i2c_do_write(obj, data[i])) {
mbed_official 82:0b31dbcd4769 265 i2c_stop(obj);
mbed_official 82:0b31dbcd4769 266 return i;
mbed_official 82:0b31dbcd4769 267 }
mbed_official 82:0b31dbcd4769 268 }
mbed_official 82:0b31dbcd4769 269
mbed_official 82:0b31dbcd4769 270 if (stop) {
mbed_official 82:0b31dbcd4769 271 i2c_stop(obj);
mbed_official 82:0b31dbcd4769 272 }
mbed_official 82:0b31dbcd4769 273
mbed_official 82:0b31dbcd4769 274 return length;
mbed_official 82:0b31dbcd4769 275 }
mbed_official 82:0b31dbcd4769 276
mbed_official 82:0b31dbcd4769 277 void i2c_reset(i2c_t *obj) {
mbed_official 82:0b31dbcd4769 278 i2c_stop(obj);
mbed_official 82:0b31dbcd4769 279 }
mbed_official 82:0b31dbcd4769 280
mbed_official 82:0b31dbcd4769 281 int i2c_byte_read(i2c_t *obj, int last) {
mbed_official 82:0b31dbcd4769 282 char data;
mbed_official 82:0b31dbcd4769 283
mbed_official 82:0b31dbcd4769 284 // set rx mode
mbed_official 82:0b31dbcd4769 285 obj->i2c->C1 &= ~I2C_C1_TX_MASK;
mbed_official 82:0b31dbcd4769 286
mbed_official 82:0b31dbcd4769 287 if(first_read) {
mbed_official 82:0b31dbcd4769 288 // first dummy read
mbed_official 82:0b31dbcd4769 289 i2c_do_read(obj, &data, 0);
mbed_official 82:0b31dbcd4769 290 first_read = 0;
mbed_official 82:0b31dbcd4769 291 }
mbed_official 82:0b31dbcd4769 292
mbed_official 82:0b31dbcd4769 293 if (last) {
mbed_official 82:0b31dbcd4769 294 // set tx mode
mbed_official 82:0b31dbcd4769 295 obj->i2c->C1 |= I2C_C1_TX_MASK;
mbed_official 82:0b31dbcd4769 296 return obj->i2c->D;
mbed_official 82:0b31dbcd4769 297 }
mbed_official 82:0b31dbcd4769 298
mbed_official 82:0b31dbcd4769 299 i2c_do_read(obj, &data, last);
mbed_official 82:0b31dbcd4769 300
mbed_official 82:0b31dbcd4769 301 return data;
mbed_official 82:0b31dbcd4769 302 }
mbed_official 82:0b31dbcd4769 303
mbed_official 82:0b31dbcd4769 304 int i2c_byte_write(i2c_t *obj, int data) {
mbed_official 82:0b31dbcd4769 305 first_read = 1;
mbed_official 82:0b31dbcd4769 306
mbed_official 82:0b31dbcd4769 307 // set tx mode
mbed_official 82:0b31dbcd4769 308 obj->i2c->C1 |= I2C_C1_TX_MASK;
mbed_official 82:0b31dbcd4769 309
mbed_official 82:0b31dbcd4769 310 return !i2c_do_write(obj, (data & 0xFF));
mbed_official 82:0b31dbcd4769 311 }
mbed_official 82:0b31dbcd4769 312
mbed_official 82:0b31dbcd4769 313
mbed_official 82:0b31dbcd4769 314 #if DEVICE_I2CSLAVE
mbed_official 82:0b31dbcd4769 315 void i2c_slave_mode(i2c_t *obj, int enable_slave) {
mbed_official 82:0b31dbcd4769 316 if (enable_slave) {
mbed_official 82:0b31dbcd4769 317 // set slave mode
mbed_official 82:0b31dbcd4769 318 obj->i2c->C1 &= ~I2C_C1_MST_MASK;
mbed_official 82:0b31dbcd4769 319 obj->i2c->C1 |= I2C_C1_IICIE_MASK;
mbed_official 82:0b31dbcd4769 320 } else {
mbed_official 82:0b31dbcd4769 321 // set master mode
mbed_official 82:0b31dbcd4769 322 obj->i2c->C1 |= I2C_C1_MST_MASK;
mbed_official 82:0b31dbcd4769 323 }
mbed_official 82:0b31dbcd4769 324 }
mbed_official 82:0b31dbcd4769 325
mbed_official 82:0b31dbcd4769 326 int i2c_slave_receive(i2c_t *obj) {
mbed_official 82:0b31dbcd4769 327 switch(obj->i2c->S) {
mbed_official 82:0b31dbcd4769 328 // read addressed
mbed_official 82:0b31dbcd4769 329 case 0xE6: return 1;
mbed_official 82:0b31dbcd4769 330
mbed_official 82:0b31dbcd4769 331 // write addressed
mbed_official 82:0b31dbcd4769 332 case 0xE2: return 3;
mbed_official 82:0b31dbcd4769 333
mbed_official 82:0b31dbcd4769 334 default: return 0;
mbed_official 82:0b31dbcd4769 335 }
mbed_official 82:0b31dbcd4769 336 }
mbed_official 82:0b31dbcd4769 337
mbed_official 82:0b31dbcd4769 338 int i2c_slave_read(i2c_t *obj, char *data, int length) {
mbed_official 82:0b31dbcd4769 339 uint8_t dummy_read;
mbed_official 82:0b31dbcd4769 340 uint8_t * ptr;
mbed_official 82:0b31dbcd4769 341 int count;
mbed_official 82:0b31dbcd4769 342
mbed_official 82:0b31dbcd4769 343 // set rx mode
mbed_official 82:0b31dbcd4769 344 obj->i2c->C1 &= ~I2C_C1_TX_MASK;
mbed_official 82:0b31dbcd4769 345
mbed_official 82:0b31dbcd4769 346 // first dummy read
mbed_official 82:0b31dbcd4769 347 dummy_read = obj->i2c->D;
mbed_official 82:0b31dbcd4769 348 if(i2c_wait_end_rx_transfer(obj)) {
mbed_official 82:0b31dbcd4769 349 return 0;
mbed_official 82:0b31dbcd4769 350 }
mbed_official 82:0b31dbcd4769 351
mbed_official 82:0b31dbcd4769 352 // read address
mbed_official 82:0b31dbcd4769 353 dummy_read = obj->i2c->D;
mbed_official 82:0b31dbcd4769 354 if(i2c_wait_end_rx_transfer(obj)) {
mbed_official 82:0b31dbcd4769 355 return 0;
mbed_official 82:0b31dbcd4769 356 }
mbed_official 82:0b31dbcd4769 357
mbed_official 82:0b31dbcd4769 358 // read (length - 1) bytes
mbed_official 82:0b31dbcd4769 359 for (count = 0; count < (length - 1); count++) {
mbed_official 82:0b31dbcd4769 360 data[count] = obj->i2c->D;
mbed_official 82:0b31dbcd4769 361 if(i2c_wait_end_rx_transfer(obj)) {
mbed_official 82:0b31dbcd4769 362 return count;
mbed_official 82:0b31dbcd4769 363 }
mbed_official 82:0b31dbcd4769 364 }
mbed_official 82:0b31dbcd4769 365
mbed_official 82:0b31dbcd4769 366 // read last byte
mbed_official 82:0b31dbcd4769 367 ptr = (length == 0) ? &dummy_read : (uint8_t *)&data[count];
mbed_official 82:0b31dbcd4769 368 *ptr = obj->i2c->D;
mbed_official 82:0b31dbcd4769 369
mbed_official 82:0b31dbcd4769 370 return (length) ? (count + 1) : 0;
mbed_official 82:0b31dbcd4769 371 }
mbed_official 82:0b31dbcd4769 372
mbed_official 82:0b31dbcd4769 373 int i2c_slave_write(i2c_t *obj, const char *data, int length) {
mbed_official 82:0b31dbcd4769 374 int i, count = 0;
mbed_official 82:0b31dbcd4769 375
mbed_official 82:0b31dbcd4769 376 // set tx mode
mbed_official 82:0b31dbcd4769 377 obj->i2c->C1 |= I2C_C1_TX_MASK;
mbed_official 82:0b31dbcd4769 378
mbed_official 82:0b31dbcd4769 379 for (i = 0; i < length; i++) {
mbed_official 82:0b31dbcd4769 380 if(i2c_do_write(obj, data[count++]) == 2) {
mbed_official 82:0b31dbcd4769 381 return i;
mbed_official 82:0b31dbcd4769 382 }
mbed_official 82:0b31dbcd4769 383 }
mbed_official 82:0b31dbcd4769 384
mbed_official 82:0b31dbcd4769 385 // set rx mode
mbed_official 82:0b31dbcd4769 386 obj->i2c->C1 &= ~I2C_C1_TX_MASK;
mbed_official 82:0b31dbcd4769 387
mbed_official 82:0b31dbcd4769 388 // dummy rx transfer needed
mbed_official 82:0b31dbcd4769 389 // otherwise the master cannot generate a stop bit
mbed_official 82:0b31dbcd4769 390 obj->i2c->D;
mbed_official 82:0b31dbcd4769 391 if(i2c_wait_end_rx_transfer(obj) == 2) {
mbed_official 82:0b31dbcd4769 392 return count;
mbed_official 82:0b31dbcd4769 393 }
mbed_official 82:0b31dbcd4769 394
mbed_official 82:0b31dbcd4769 395 return count;
mbed_official 82:0b31dbcd4769 396 }
mbed_official 82:0b31dbcd4769 397
mbed_official 82:0b31dbcd4769 398 void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask) {
mbed_official 82:0b31dbcd4769 399 obj->i2c->A1 = address & 0xfe;
mbed_official 82:0b31dbcd4769 400 }
mbed_official 82:0b31dbcd4769 401 #endif
mbed_official 82:0b31dbcd4769 402