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mbed library sources

Dependents:   Encrypted my_mbed lklk CyaSSL_DTLS_Cellular ... more

Superseded

This library was superseded by mbed-dev - https://os.mbed.com/users/mbed_official/code/mbed-dev/.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_NORDIC/TARGET_NRF51822/i2c_api.c@227:7bd0639b8911, 2014-06-11 (annotated)

Committer:
mbed_official
Date:
Wed Jun 11 16:00:09 2014 +0100
Revision:
227:7bd0639b8911
Parent:
177:d57c40a064c8 
Synchronized with git revision d58d532ebc0e0a96f4fffb8edefc082b71b964af



Full URL: https://github.com/mbedmicro/mbed/commit/d58d532ebc0e0a96f4fffb8edefc082b71b964af/

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 85:e1a8e879a6a9 1 /* mbed Microcontroller Library
mbed_official 104:a6a92e2e5a92 2 * Copyright (c) 2013 Nordic Semiconductor
mbed_official 85:e1a8e879a6a9 3 *
mbed_official 85:e1a8e879a6a9 4 * Licensed under the Apache License, Version 2.0 (the "License");
mbed_official 85:e1a8e879a6a9 5 * you may not use this file except in compliance with the License.
mbed_official 85:e1a8e879a6a9 6 * You may obtain a copy of the License at
mbed_official 85:e1a8e879a6a9 7 *
mbed_official 85:e1a8e879a6a9 8 * http://www.apache.org/licenses/LICENSE-2.0
mbed_official 85:e1a8e879a6a9 9 *
mbed_official 85:e1a8e879a6a9 10 * Unless required by applicable law or agreed to in writing, software
mbed_official 85:e1a8e879a6a9 11 * distributed under the License is distributed on an "AS IS" BASIS,
mbed_official 85:e1a8e879a6a9 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
mbed_official 85:e1a8e879a6a9 13 * See the License for the specific language governing permissions and
mbed_official 85:e1a8e879a6a9 14 * limitations under the License.
mbed_official 85:e1a8e879a6a9 15 */
mbed_official 227:7bd0639b8911 16 #include "mbed_assert.h"
mbed_official 85:e1a8e879a6a9 17 #include "i2c_api.h"
mbed_official 85:e1a8e879a6a9 18 #include "cmsis.h"
mbed_official 85:e1a8e879a6a9 19 #include "pinmap.h"
mbed_official 85:e1a8e879a6a9 20
mbed_official 85:e1a8e879a6a9 21 static const PinMap PinMap_I2C_SDA[] = {
mbed_official 85:e1a8e879a6a9 22 {p22, I2C_0, 1},
mbed_official 85:e1a8e879a6a9 23 {p13, I2C_1, 2},
mbed_official 85:e1a8e879a6a9 24 {NC , NC , 0}
mbed_official 85:e1a8e879a6a9 25 };
mbed_official 85:e1a8e879a6a9 26
mbed_official 85:e1a8e879a6a9 27 static const PinMap PinMap_I2C_SCL[] = {
mbed_official 85:e1a8e879a6a9 28 {p20, I2C_0, 1},
mbed_official 85:e1a8e879a6a9 29 {p15, I2C_1, 2},
mbed_official 85:e1a8e879a6a9 30 {NC , NC, 0}
mbed_official 85:e1a8e879a6a9 31 };
mbed_official 85:e1a8e879a6a9 32
mbed_official 85:e1a8e879a6a9 33 uint8_t addrSet=0;
mbed_official 85:e1a8e879a6a9 34
mbed_official 85:e1a8e879a6a9 35 void i2c_interface_enable(i2c_t *obj){
mbed_official 85:e1a8e879a6a9 36 obj->i2c->ENABLE = (TWI_ENABLE_ENABLE_Enabled << TWI_ENABLE_ENABLE_Pos);
mbed_official 85:e1a8e879a6a9 37 }
mbed_official 85:e1a8e879a6a9 38
mbed_official 85:e1a8e879a6a9 39 void twi_master_init(i2c_t *obj, PinName sda, PinName scl, int frequency) {
mbed_official 85:e1a8e879a6a9 40 NRF_GPIO->PIN_CNF[scl] = ((GPIO_PIN_CNF_DIR_Input << GPIO_PIN_CNF_DIR_Pos) |
mbed_official 85:e1a8e879a6a9 41 (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) |
mbed_official 85:e1a8e879a6a9 42 (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos) |
mbed_official 85:e1a8e879a6a9 43 (GPIO_PIN_CNF_DRIVE_S0D1 << GPIO_PIN_CNF_DRIVE_Pos) |
mbed_official 85:e1a8e879a6a9 44 (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos));
mbed_official 85:e1a8e879a6a9 45
mbed_official 85:e1a8e879a6a9 46 NRF_GPIO->PIN_CNF[sda] = ((GPIO_PIN_CNF_DIR_Input << GPIO_PIN_CNF_DIR_Pos) |
mbed_official 85:e1a8e879a6a9 47 (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) |
mbed_official 85:e1a8e879a6a9 48 (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos) |
mbed_official 85:e1a8e879a6a9 49 (GPIO_PIN_CNF_DRIVE_S0D1 << GPIO_PIN_CNF_DRIVE_Pos) |
mbed_official 85:e1a8e879a6a9 50 (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos));
mbed_official 85:e1a8e879a6a9 51
mbed_official 85:e1a8e879a6a9 52 obj->i2c->PSELSCL = scl;
mbed_official 227:7bd0639b8911 53 obj->i2c->PSELSDA = sda;
mbed_official 85:e1a8e879a6a9 54 // set default frequency at 100k
mbed_official 85:e1a8e879a6a9 55 i2c_frequency(obj, frequency);
mbed_official 85:e1a8e879a6a9 56 i2c_interface_enable(obj);
mbed_official 85:e1a8e879a6a9 57 }
mbed_official 85:e1a8e879a6a9 58 void i2c_init(i2c_t *obj, PinName sda, PinName scl) {
mbed_official 85:e1a8e879a6a9 59 // determine the SPI to use
mbed_official 85:e1a8e879a6a9 60 I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA);
mbed_official 85:e1a8e879a6a9 61 I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL);
mbed_official 85:e1a8e879a6a9 62 I2CName i2c = (I2CName)pinmap_merge(i2c_sda,i2c_scl);
mbed_official 85:e1a8e879a6a9 63 obj->i2c = (NRF_TWI_Type *)i2c;
mbed_official 85:e1a8e879a6a9 64
mbed_official 227:7bd0639b8911 65 MBED_ASSERT((int)obj->i2c != NC);
mbed_official 85:e1a8e879a6a9 66
mbed_official 85:e1a8e879a6a9 67 obj->scl=scl;
mbed_official 85:e1a8e879a6a9 68 obj->sda=sda;
mbed_official 85:e1a8e879a6a9 69 obj->i2c->EVENTS_ERROR = 0;
mbed_official 227:7bd0639b8911 70 obj->i2c->ENABLE = TWI_ENABLE_ENABLE_Disabled << TWI_ENABLE_ENABLE_Pos;
mbed_official 227:7bd0639b8911 71 obj->i2c->POWER = 0;
mbed_official 85:e1a8e879a6a9 72
mbed_official 85:e1a8e879a6a9 73 for(int i=0;i<100;i++){
mbed_official 85:e1a8e879a6a9 74 }
mbed_official 85:e1a8e879a6a9 75
mbed_official 227:7bd0639b8911 76 obj->i2c->POWER = 1;
mbed_official 85:e1a8e879a6a9 77 twi_master_init(obj,sda,scl,100000);
mbed_official 85:e1a8e879a6a9 78 }
mbed_official 85:e1a8e879a6a9 79 void i2c_reset(i2c_t *obj) {
mbed_official 85:e1a8e879a6a9 80 obj->i2c->EVENTS_ERROR = 0;
mbed_official 227:7bd0639b8911 81 obj->i2c->ENABLE = TWI_ENABLE_ENABLE_Disabled << TWI_ENABLE_ENABLE_Pos;
mbed_official 227:7bd0639b8911 82 obj->i2c->POWER = 0;
mbed_official 85:e1a8e879a6a9 83 for(int i=0;i<100;i++){
mbed_official 85:e1a8e879a6a9 84 }
mbed_official 85:e1a8e879a6a9 85
mbed_official 227:7bd0639b8911 86 obj->i2c->POWER = 1;
mbed_official 85:e1a8e879a6a9 87 twi_master_init(obj,obj->sda,obj->scl,obj->freq);
mbed_official 85:e1a8e879a6a9 88 }
mbed_official 85:e1a8e879a6a9 89
mbed_official 85:e1a8e879a6a9 90 int i2c_start(i2c_t *obj) {
mbed_official 85:e1a8e879a6a9 91 int status = 0;
mbed_official 85:e1a8e879a6a9 92 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 93 addrSet=0;
mbed_official 85:e1a8e879a6a9 94 return status;
mbed_official 85:e1a8e879a6a9 95 }
mbed_official 85:e1a8e879a6a9 96
mbed_official 85:e1a8e879a6a9 97 int i2c_stop(i2c_t *obj) {
mbed_official 85:e1a8e879a6a9 98 int timeOut = 100000;
mbed_official 85:e1a8e879a6a9 99 obj->i2c->EVENTS_STOPPED = 0;
mbed_official 85:e1a8e879a6a9 100 // write the stop bit
mbed_official 85:e1a8e879a6a9 101 obj->i2c->TASKS_STOP = 1;
mbed_official 85:e1a8e879a6a9 102 while(!obj->i2c->EVENTS_STOPPED){
mbed_official 85:e1a8e879a6a9 103 timeOut--;
mbed_official 85:e1a8e879a6a9 104 if(timeOut<0)
mbed_official 85:e1a8e879a6a9 105 return 1;
mbed_official 227:7bd0639b8911 106 }
mbed_official 85:e1a8e879a6a9 107 addrSet = 0;
mbed_official 85:e1a8e879a6a9 108 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 109 return 0;
mbed_official 85:e1a8e879a6a9 110 }
mbed_official 85:e1a8e879a6a9 111
mbed_official 85:e1a8e879a6a9 112
mbed_official 85:e1a8e879a6a9 113 int i2c_do_write(i2c_t *obj, int value) {
mbed_official 85:e1a8e879a6a9 114 int timeOut = 100000;
mbed_official 85:e1a8e879a6a9 115 obj->i2c->TXD = value;
mbed_official 85:e1a8e879a6a9 116 while(!obj->i2c->EVENTS_TXDSENT){
mbed_official 85:e1a8e879a6a9 117 timeOut--;
mbed_official 85:e1a8e879a6a9 118 if(timeOut<0)
mbed_official 85:e1a8e879a6a9 119 return 1;
mbed_official 85:e1a8e879a6a9 120 }
mbed_official 227:7bd0639b8911 121 obj->i2c->EVENTS_TXDSENT = 0;
mbed_official 85:e1a8e879a6a9 122 return 0;
mbed_official 85:e1a8e879a6a9 123 }
mbed_official 85:e1a8e879a6a9 124
mbed_official 85:e1a8e879a6a9 125 int i2c_do_read(i2c_t *obj, char * data, int last) {
mbed_official 85:e1a8e879a6a9 126 int timeOut = 100000;
mbed_official 177:d57c40a064c8 127
mbed_official 177:d57c40a064c8 128 if (last){
mbed_official 177:d57c40a064c8 129 obj->i2c->TASKS_STOP = 1;
mbed_official 177:d57c40a064c8 130 }
mbed_official 85:e1a8e879a6a9 131 while(!obj->i2c->EVENTS_RXDREADY){
mbed_official 85:e1a8e879a6a9 132 timeOut--;
mbed_official 85:e1a8e879a6a9 133 if(timeOut<0)
mbed_official 85:e1a8e879a6a9 134 return 1;
mbed_official 85:e1a8e879a6a9 135 }
mbed_official 85:e1a8e879a6a9 136 obj->i2c->EVENTS_RXDREADY = 0;
mbed_official 177:d57c40a064c8 137
mbed_official 85:e1a8e879a6a9 138 *data = obj->i2c->RXD;
mbed_official 85:e1a8e879a6a9 139
mbed_official 85:e1a8e879a6a9 140 for(int i=0;i<320;i++){
mbed_official 85:e1a8e879a6a9 141 }
mbed_official 85:e1a8e879a6a9 142
mbed_official 85:e1a8e879a6a9 143 obj->i2c->TASKS_RESUME = 1;
mbed_official 85:e1a8e879a6a9 144
mbed_official 85:e1a8e879a6a9 145 return 0;
mbed_official 85:e1a8e879a6a9 146 }
mbed_official 85:e1a8e879a6a9 147
mbed_official 85:e1a8e879a6a9 148
mbed_official 85:e1a8e879a6a9 149 void i2c_frequency(i2c_t *obj, int hz) {
mbed_official 85:e1a8e879a6a9 150 if(hz<250000){
mbed_official 85:e1a8e879a6a9 151 obj->freq = 100000;
mbed_official 85:e1a8e879a6a9 152 obj->i2c->FREQUENCY = (TWI_FREQUENCY_FREQUENCY_K100 << TWI_FREQUENCY_FREQUENCY_Pos);
mbed_official 85:e1a8e879a6a9 153 }
mbed_official 85:e1a8e879a6a9 154 else if(hz<400000){
mbed_official 85:e1a8e879a6a9 155 obj->freq = 250000;
mbed_official 85:e1a8e879a6a9 156 obj->i2c->FREQUENCY = (TWI_FREQUENCY_FREQUENCY_K250 << TWI_FREQUENCY_FREQUENCY_Pos);
mbed_official 85:e1a8e879a6a9 157 }
mbed_official 85:e1a8e879a6a9 158 else{
mbed_official 85:e1a8e879a6a9 159 obj->freq = 400000;
mbed_official 85:e1a8e879a6a9 160 obj->i2c->FREQUENCY = (TWI_FREQUENCY_FREQUENCY_K400 << TWI_FREQUENCY_FREQUENCY_Pos);
mbed_official 85:e1a8e879a6a9 161 }
mbed_official 85:e1a8e879a6a9 162 }
mbed_official 85:e1a8e879a6a9 163
mbed_official 85:e1a8e879a6a9 164 int checkError(i2c_t *obj){
mbed_official 227:7bd0639b8911 165 if (obj->i2c->EVENTS_ERROR == 1){
mbed_official 227:7bd0639b8911 166 if (obj->i2c->ERRORSRC & TWI_ERRORSRC_ANACK_Msk){
mbed_official 85:e1a8e879a6a9 167 obj->i2c->EVENTS_ERROR = 0;
mbed_official 227:7bd0639b8911 168 obj->i2c->TASKS_STOP = 1;
mbed_official 85:e1a8e879a6a9 169 return I2C_ERROR_BUS_BUSY;
mbed_official 85:e1a8e879a6a9 170 }
mbed_official 85:e1a8e879a6a9 171
mbed_official 85:e1a8e879a6a9 172 obj->i2c->EVENTS_ERROR = 0;
mbed_official 85:e1a8e879a6a9 173 obj->i2c->TASKS_STOP = 1;
mbed_official 227:7bd0639b8911 174 return I2C_ERROR_NO_SLAVE;
mbed_official 227:7bd0639b8911 175 }
mbed_official 85:e1a8e879a6a9 176 return 0;
mbed_official 85:e1a8e879a6a9 177 }
mbed_official 85:e1a8e879a6a9 178
mbed_official 85:e1a8e879a6a9 179 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) {
mbed_official 85:e1a8e879a6a9 180 int status,count,errorResult;
mbed_official 85:e1a8e879a6a9 181 obj->i2c->ADDRESS = (address>>1);
mbed_official 85:e1a8e879a6a9 182 obj->i2c->SHORTS = 0;
mbed_official 85:e1a8e879a6a9 183 obj->i2c->EVENTS_RXDREADY = 0;
mbed_official 85:e1a8e879a6a9 184 obj->i2c->TASKS_STARTRX = 1;
mbed_official 85:e1a8e879a6a9 185
mbed_official 85:e1a8e879a6a9 186 // Read in all except last byte
mbed_official 85:e1a8e879a6a9 187 for (count = 0; count < (length - 1); count++) {
mbed_official 85:e1a8e879a6a9 188 status = i2c_do_read(obj,&data[count], 0);
mbed_official 227:7bd0639b8911 189 if (status) {
mbed_official 85:e1a8e879a6a9 190 errorResult = checkError(obj);
mbed_official 85:e1a8e879a6a9 191 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 192 if(errorResult<0){
mbed_official 85:e1a8e879a6a9 193 return errorResult;
mbed_official 85:e1a8e879a6a9 194 }
mbed_official 85:e1a8e879a6a9 195 return count;
mbed_official 85:e1a8e879a6a9 196 }
mbed_official 85:e1a8e879a6a9 197 }
mbed_official 85:e1a8e879a6a9 198
mbed_official 85:e1a8e879a6a9 199 // read in last byte
mbed_official 85:e1a8e879a6a9 200 status = i2c_do_read(obj,&data[length-1], 1);
mbed_official 85:e1a8e879a6a9 201 if (status) {
mbed_official 85:e1a8e879a6a9 202 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 203 return length - 1;
mbed_official 85:e1a8e879a6a9 204 }
mbed_official 85:e1a8e879a6a9 205 // If not repeated start, send stop.
mbed_official 85:e1a8e879a6a9 206 if (stop) {
mbed_official 85:e1a8e879a6a9 207 while(!obj->i2c->EVENTS_STOPPED){
mbed_official 85:e1a8e879a6a9 208 }
mbed_official 85:e1a8e879a6a9 209 obj->i2c->EVENTS_STOPPED = 0;
mbed_official 227:7bd0639b8911 210 }
mbed_official 85:e1a8e879a6a9 211 return length;
mbed_official 85:e1a8e879a6a9 212 }
mbed_official 85:e1a8e879a6a9 213
mbed_official 85:e1a8e879a6a9 214 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) {
mbed_official 85:e1a8e879a6a9 215 int status, errorResult;
mbed_official 85:e1a8e879a6a9 216 obj->i2c->ADDRESS = (address>>1);
mbed_official 85:e1a8e879a6a9 217 obj->i2c->SHORTS = 0;
mbed_official 227:7bd0639b8911 218 obj->i2c->TASKS_STARTTX = 1;
mbed_official 85:e1a8e879a6a9 219
mbed_official 85:e1a8e879a6a9 220 for (int i=0; i<length; i++) {
mbed_official 85:e1a8e879a6a9 221 status = i2c_do_write(obj, data[i]);
mbed_official 85:e1a8e879a6a9 222 if(status) {
mbed_official 85:e1a8e879a6a9 223 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 224 errorResult = checkError(obj);
mbed_official 85:e1a8e879a6a9 225 if(errorResult<0){
mbed_official 85:e1a8e879a6a9 226 return errorResult;
mbed_official 85:e1a8e879a6a9 227 }
mbed_official 85:e1a8e879a6a9 228 return i;
mbed_official 85:e1a8e879a6a9 229 }
mbed_official 85:e1a8e879a6a9 230 }
mbed_official 85:e1a8e879a6a9 231
mbed_official 85:e1a8e879a6a9 232 // If not repeated start, send stop.
mbed_official 85:e1a8e879a6a9 233 if (stop) {
mbed_official 85:e1a8e879a6a9 234 if(i2c_stop(obj)){
mbed_official 85:e1a8e879a6a9 235 return I2C_ERROR_NO_SLAVE;
mbed_official 85:e1a8e879a6a9 236 }
mbed_official 85:e1a8e879a6a9 237 }
mbed_official 85:e1a8e879a6a9 238 return length;
mbed_official 85:e1a8e879a6a9 239 }
mbed_official 85:e1a8e879a6a9 240
mbed_official 85:e1a8e879a6a9 241 int i2c_byte_read(i2c_t *obj, int last) {
mbed_official 85:e1a8e879a6a9 242 char data;
mbed_official 85:e1a8e879a6a9 243 int status;
mbed_official 85:e1a8e879a6a9 244
mbed_official 85:e1a8e879a6a9 245 status = i2c_do_read(obj,&data, last);
mbed_official 85:e1a8e879a6a9 246 if (status) {
mbed_official 85:e1a8e879a6a9 247 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 248 }
mbed_official 85:e1a8e879a6a9 249 return data;
mbed_official 85:e1a8e879a6a9 250 }
mbed_official 85:e1a8e879a6a9 251
mbed_official 85:e1a8e879a6a9 252 int i2c_byte_write(i2c_t *obj, int data) {
mbed_official 85:e1a8e879a6a9 253 int status = 0;
mbed_official 85:e1a8e879a6a9 254 if(!addrSet){
mbed_official 85:e1a8e879a6a9 255 addrSet = 1;
mbed_official 85:e1a8e879a6a9 256 obj->i2c->ADDRESS = (data>>1);
mbed_official 85:e1a8e879a6a9 257
mbed_official 85:e1a8e879a6a9 258 if(data&1){
mbed_official 85:e1a8e879a6a9 259 obj->i2c->EVENTS_RXDREADY = 0;
mbed_official 85:e1a8e879a6a9 260 obj->i2c->TASKS_STARTRX = 1;
mbed_official 85:e1a8e879a6a9 261 }
mbed_official 85:e1a8e879a6a9 262 else{
mbed_official 227:7bd0639b8911 263 obj->i2c->TASKS_STARTTX = 1;
mbed_official 85:e1a8e879a6a9 264 }
mbed_official 85:e1a8e879a6a9 265 }
mbed_official 85:e1a8e879a6a9 266 else{
mbed_official 85:e1a8e879a6a9 267 status = i2c_do_write(obj, data);
mbed_official 85:e1a8e879a6a9 268 if(status) {
mbed_official 85:e1a8e879a6a9 269 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 270 }
mbed_official 85:e1a8e879a6a9 271 }
mbed_official 85:e1a8e879a6a9 272 return (1-status);
mbed_official 85:e1a8e879a6a9 273 }