mbed official / mbed-src

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Superseded

This library was superseded by mbed-dev - https://os.mbed.com/users/mbed_official/code/mbed-dev/.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@85:e1a8e879a6a9, 2014-02-07 (annotated)

Committer:
mbed_official
Date:
Fri Feb 07 18:00:11 2014 +0000
Revision:
85:e1a8e879a6a9
Child:
104:a6a92e2e5a92
Synchronized with git revision 4b2b368a6a3b1f0fd33d99917981c67436c4aebe



Full URL: https://github.com/mbedmicro/mbed/commit/4b2b368a6a3b1f0fd33d99917981c67436c4aebe/

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 85:e1a8e879a6a9 1 /* mbed Microcontroller Library
mbed_official 85:e1a8e879a6a9 2 * Copyright (c) 2006-2013 ARM Limited
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 85:e1a8e879a6a9 16 #include "i2c_api.h"
mbed_official 85:e1a8e879a6a9 17 #include "cmsis.h"
mbed_official 85:e1a8e879a6a9 18 #include "pinmap.h"
mbed_official 85:e1a8e879a6a9 19 #include "error.h"
mbed_official 85:e1a8e879a6a9 20
mbed_official 85:e1a8e879a6a9 21
mbed_official 85:e1a8e879a6a9 22
mbed_official 85:e1a8e879a6a9 23 static const PinMap PinMap_I2C_SDA[] = {
mbed_official 85:e1a8e879a6a9 24 {p22, I2C_0, 1},
mbed_official 85:e1a8e879a6a9 25 {p13, I2C_1, 2},
mbed_official 85:e1a8e879a6a9 26 {NC , NC , 0}
mbed_official 85:e1a8e879a6a9 27 };
mbed_official 85:e1a8e879a6a9 28
mbed_official 85:e1a8e879a6a9 29 static const PinMap PinMap_I2C_SCL[] = {
mbed_official 85:e1a8e879a6a9 30 {p20, I2C_0, 1},
mbed_official 85:e1a8e879a6a9 31 {p15, I2C_1, 2},
mbed_official 85:e1a8e879a6a9 32 {NC , NC, 0}
mbed_official 85:e1a8e879a6a9 33 };
mbed_official 85:e1a8e879a6a9 34
mbed_official 85:e1a8e879a6a9 35 uint8_t addrSet=0;
mbed_official 85:e1a8e879a6a9 36
mbed_official 85:e1a8e879a6a9 37 void i2c_interface_enable(i2c_t *obj){
mbed_official 85:e1a8e879a6a9 38 obj->i2c->ENABLE = (TWI_ENABLE_ENABLE_Enabled << TWI_ENABLE_ENABLE_Pos);
mbed_official 85:e1a8e879a6a9 39 }
mbed_official 85:e1a8e879a6a9 40
mbed_official 85:e1a8e879a6a9 41 void twi_master_init(i2c_t *obj, PinName sda, PinName scl, int frequency) {
mbed_official 85:e1a8e879a6a9 42 NRF_GPIO->PIN_CNF[scl] = ((GPIO_PIN_CNF_DIR_Input << GPIO_PIN_CNF_DIR_Pos) |
mbed_official 85:e1a8e879a6a9 43 (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) |
mbed_official 85:e1a8e879a6a9 44 (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos) |
mbed_official 85:e1a8e879a6a9 45 (GPIO_PIN_CNF_DRIVE_S0D1 << GPIO_PIN_CNF_DRIVE_Pos) |
mbed_official 85:e1a8e879a6a9 46 (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos));
mbed_official 85:e1a8e879a6a9 47
mbed_official 85:e1a8e879a6a9 48 NRF_GPIO->PIN_CNF[sda] = ((GPIO_PIN_CNF_DIR_Input << GPIO_PIN_CNF_DIR_Pos) |
mbed_official 85:e1a8e879a6a9 49 (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos) |
mbed_official 85:e1a8e879a6a9 50 (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos) |
mbed_official 85:e1a8e879a6a9 51 (GPIO_PIN_CNF_DRIVE_S0D1 << GPIO_PIN_CNF_DRIVE_Pos) |
mbed_official 85:e1a8e879a6a9 52 (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos));
mbed_official 85:e1a8e879a6a9 53
mbed_official 85:e1a8e879a6a9 54 obj->i2c->PSELSCL = scl;
mbed_official 85:e1a8e879a6a9 55 obj->i2c->PSELSDA = sda;
mbed_official 85:e1a8e879a6a9 56 // set default frequency at 100k
mbed_official 85:e1a8e879a6a9 57 i2c_frequency(obj, frequency);
mbed_official 85:e1a8e879a6a9 58 i2c_interface_enable(obj);
mbed_official 85:e1a8e879a6a9 59 }
mbed_official 85:e1a8e879a6a9 60 void i2c_init(i2c_t *obj, PinName sda, PinName scl) {
mbed_official 85:e1a8e879a6a9 61 // determine the SPI to use
mbed_official 85:e1a8e879a6a9 62 I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA);
mbed_official 85:e1a8e879a6a9 63 I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL);
mbed_official 85:e1a8e879a6a9 64 I2CName i2c = (I2CName)pinmap_merge(i2c_sda,i2c_scl);
mbed_official 85:e1a8e879a6a9 65 obj->i2c = (NRF_TWI_Type *)i2c;
mbed_official 85:e1a8e879a6a9 66
mbed_official 85:e1a8e879a6a9 67 if ((int)obj->i2c == NC) {
mbed_official 85:e1a8e879a6a9 68 error("I2C pin mapping failed");
mbed_official 85:e1a8e879a6a9 69 }
mbed_official 85:e1a8e879a6a9 70
mbed_official 85:e1a8e879a6a9 71 obj->scl=scl;
mbed_official 85:e1a8e879a6a9 72 obj->sda=sda;
mbed_official 85:e1a8e879a6a9 73 obj->i2c->EVENTS_ERROR = 0;
mbed_official 85:e1a8e879a6a9 74 obj->i2c->ENABLE = TWI_ENABLE_ENABLE_Disabled << TWI_ENABLE_ENABLE_Pos;
mbed_official 85:e1a8e879a6a9 75 obj->i2c->POWER = 0;
mbed_official 85:e1a8e879a6a9 76
mbed_official 85:e1a8e879a6a9 77 for(int i=0;i<100;i++){
mbed_official 85:e1a8e879a6a9 78 }
mbed_official 85:e1a8e879a6a9 79
mbed_official 85:e1a8e879a6a9 80 obj->i2c->POWER = 1;
mbed_official 85:e1a8e879a6a9 81 twi_master_init(obj,sda,scl,100000);
mbed_official 85:e1a8e879a6a9 82 }
mbed_official 85:e1a8e879a6a9 83 void i2c_reset(i2c_t *obj) {
mbed_official 85:e1a8e879a6a9 84 obj->i2c->EVENTS_ERROR = 0;
mbed_official 85:e1a8e879a6a9 85 obj->i2c->ENABLE = TWI_ENABLE_ENABLE_Disabled << TWI_ENABLE_ENABLE_Pos;
mbed_official 85:e1a8e879a6a9 86 obj->i2c->POWER = 0;
mbed_official 85:e1a8e879a6a9 87 for(int i=0;i<100;i++){
mbed_official 85:e1a8e879a6a9 88 }
mbed_official 85:e1a8e879a6a9 89
mbed_official 85:e1a8e879a6a9 90 obj->i2c->POWER = 1;
mbed_official 85:e1a8e879a6a9 91 twi_master_init(obj,obj->sda,obj->scl,obj->freq);
mbed_official 85:e1a8e879a6a9 92 }
mbed_official 85:e1a8e879a6a9 93
mbed_official 85:e1a8e879a6a9 94 int i2c_start(i2c_t *obj) {
mbed_official 85:e1a8e879a6a9 95 int status = 0;
mbed_official 85:e1a8e879a6a9 96 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 97 addrSet=0;
mbed_official 85:e1a8e879a6a9 98 return status;
mbed_official 85:e1a8e879a6a9 99 }
mbed_official 85:e1a8e879a6a9 100
mbed_official 85:e1a8e879a6a9 101 int i2c_stop(i2c_t *obj) {
mbed_official 85:e1a8e879a6a9 102 int timeOut = 100000;
mbed_official 85:e1a8e879a6a9 103 obj->i2c->EVENTS_STOPPED = 0;
mbed_official 85:e1a8e879a6a9 104 // write the stop bit
mbed_official 85:e1a8e879a6a9 105 obj->i2c->TASKS_STOP = 1;
mbed_official 85:e1a8e879a6a9 106 while(!obj->i2c->EVENTS_STOPPED){
mbed_official 85:e1a8e879a6a9 107 timeOut--;
mbed_official 85:e1a8e879a6a9 108 if(timeOut<0)
mbed_official 85:e1a8e879a6a9 109 return 1;
mbed_official 85:e1a8e879a6a9 110 }
mbed_official 85:e1a8e879a6a9 111 addrSet = 0;
mbed_official 85:e1a8e879a6a9 112 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 113 return 0;
mbed_official 85:e1a8e879a6a9 114 }
mbed_official 85:e1a8e879a6a9 115
mbed_official 85:e1a8e879a6a9 116
mbed_official 85:e1a8e879a6a9 117 int i2c_do_write(i2c_t *obj, int value) {
mbed_official 85:e1a8e879a6a9 118 int timeOut = 100000;
mbed_official 85:e1a8e879a6a9 119 obj->i2c->TXD = value;
mbed_official 85:e1a8e879a6a9 120 while(!obj->i2c->EVENTS_TXDSENT){
mbed_official 85:e1a8e879a6a9 121 timeOut--;
mbed_official 85:e1a8e879a6a9 122 if(timeOut<0)
mbed_official 85:e1a8e879a6a9 123 return 1;
mbed_official 85:e1a8e879a6a9 124 }
mbed_official 85:e1a8e879a6a9 125 obj->i2c->EVENTS_TXDSENT = 0;
mbed_official 85:e1a8e879a6a9 126 return 0;
mbed_official 85:e1a8e879a6a9 127 }
mbed_official 85:e1a8e879a6a9 128
mbed_official 85:e1a8e879a6a9 129 int i2c_do_read(i2c_t *obj, char * data, int last) {
mbed_official 85:e1a8e879a6a9 130 int timeOut = 100000;
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 85:e1a8e879a6a9 137
mbed_official 85:e1a8e879a6a9 138 if (last){
mbed_official 85:e1a8e879a6a9 139 obj->i2c->TASKS_STOP = 1;
mbed_official 85:e1a8e879a6a9 140 }
mbed_official 85:e1a8e879a6a9 141 *data = obj->i2c->RXD;
mbed_official 85:e1a8e879a6a9 142
mbed_official 85:e1a8e879a6a9 143 for(int i=0;i<320;i++){
mbed_official 85:e1a8e879a6a9 144 }
mbed_official 85:e1a8e879a6a9 145
mbed_official 85:e1a8e879a6a9 146 obj->i2c->TASKS_RESUME = 1;
mbed_official 85:e1a8e879a6a9 147
mbed_official 85:e1a8e879a6a9 148 return 0;
mbed_official 85:e1a8e879a6a9 149 }
mbed_official 85:e1a8e879a6a9 150
mbed_official 85:e1a8e879a6a9 151
mbed_official 85:e1a8e879a6a9 152 void i2c_frequency(i2c_t *obj, int hz) {
mbed_official 85:e1a8e879a6a9 153 if(hz<250000){
mbed_official 85:e1a8e879a6a9 154 obj->freq = 100000;
mbed_official 85:e1a8e879a6a9 155 obj->i2c->FREQUENCY = (TWI_FREQUENCY_FREQUENCY_K100 << TWI_FREQUENCY_FREQUENCY_Pos);
mbed_official 85:e1a8e879a6a9 156 }
mbed_official 85:e1a8e879a6a9 157 else if(hz<400000){
mbed_official 85:e1a8e879a6a9 158 obj->freq = 250000;
mbed_official 85:e1a8e879a6a9 159 obj->i2c->FREQUENCY = (TWI_FREQUENCY_FREQUENCY_K250 << TWI_FREQUENCY_FREQUENCY_Pos);
mbed_official 85:e1a8e879a6a9 160 }
mbed_official 85:e1a8e879a6a9 161 else{
mbed_official 85:e1a8e879a6a9 162 obj->freq = 400000;
mbed_official 85:e1a8e879a6a9 163 obj->i2c->FREQUENCY = (TWI_FREQUENCY_FREQUENCY_K400 << TWI_FREQUENCY_FREQUENCY_Pos);
mbed_official 85:e1a8e879a6a9 164 }
mbed_official 85:e1a8e879a6a9 165 }
mbed_official 85:e1a8e879a6a9 166
mbed_official 85:e1a8e879a6a9 167 int checkError(i2c_t *obj){
mbed_official 85:e1a8e879a6a9 168 if (obj->i2c->EVENTS_ERROR == 1){
mbed_official 85:e1a8e879a6a9 169 if (obj->i2c->ERRORSRC & TWI_ERRORSRC_ANACK_Msk){
mbed_official 85:e1a8e879a6a9 170 obj->i2c->EVENTS_ERROR = 0;
mbed_official 85:e1a8e879a6a9 171 obj->i2c->TASKS_STOP = 1;
mbed_official 85:e1a8e879a6a9 172 return I2C_ERROR_BUS_BUSY;
mbed_official 85:e1a8e879a6a9 173 }
mbed_official 85:e1a8e879a6a9 174
mbed_official 85:e1a8e879a6a9 175 obj->i2c->EVENTS_ERROR = 0;
mbed_official 85:e1a8e879a6a9 176 obj->i2c->TASKS_STOP = 1;
mbed_official 85:e1a8e879a6a9 177 return I2C_ERROR_NO_SLAVE;
mbed_official 85:e1a8e879a6a9 178 }
mbed_official 85:e1a8e879a6a9 179 return 0;
mbed_official 85:e1a8e879a6a9 180 }
mbed_official 85:e1a8e879a6a9 181
mbed_official 85:e1a8e879a6a9 182 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) {
mbed_official 85:e1a8e879a6a9 183 int status,count,errorResult;
mbed_official 85:e1a8e879a6a9 184 obj->i2c->ADDRESS = (address>>1);
mbed_official 85:e1a8e879a6a9 185 obj->i2c->SHORTS = 0;
mbed_official 85:e1a8e879a6a9 186 obj->i2c->EVENTS_RXDREADY = 0;
mbed_official 85:e1a8e879a6a9 187 obj->i2c->TASKS_STARTRX = 1;
mbed_official 85:e1a8e879a6a9 188
mbed_official 85:e1a8e879a6a9 189 // Read in all except last byte
mbed_official 85:e1a8e879a6a9 190 for (count = 0; count < (length - 1); count++) {
mbed_official 85:e1a8e879a6a9 191 status = i2c_do_read(obj,&data[count], 0);
mbed_official 85:e1a8e879a6a9 192 if (status) {
mbed_official 85:e1a8e879a6a9 193 errorResult = checkError(obj);
mbed_official 85:e1a8e879a6a9 194 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 195 if(errorResult<0){
mbed_official 85:e1a8e879a6a9 196 return errorResult;
mbed_official 85:e1a8e879a6a9 197 }
mbed_official 85:e1a8e879a6a9 198 return count;
mbed_official 85:e1a8e879a6a9 199 }
mbed_official 85:e1a8e879a6a9 200 }
mbed_official 85:e1a8e879a6a9 201
mbed_official 85:e1a8e879a6a9 202 // read in last byte
mbed_official 85:e1a8e879a6a9 203 status = i2c_do_read(obj,&data[length-1], 1);
mbed_official 85:e1a8e879a6a9 204 if (status) {
mbed_official 85:e1a8e879a6a9 205 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 206 return length - 1;
mbed_official 85:e1a8e879a6a9 207 }
mbed_official 85:e1a8e879a6a9 208 // If not repeated start, send stop.
mbed_official 85:e1a8e879a6a9 209 if (stop) {
mbed_official 85:e1a8e879a6a9 210 while(!obj->i2c->EVENTS_STOPPED){
mbed_official 85:e1a8e879a6a9 211 }
mbed_official 85:e1a8e879a6a9 212 obj->i2c->EVENTS_STOPPED = 0;
mbed_official 85:e1a8e879a6a9 213 }
mbed_official 85:e1a8e879a6a9 214 return length;
mbed_official 85:e1a8e879a6a9 215 }
mbed_official 85:e1a8e879a6a9 216
mbed_official 85:e1a8e879a6a9 217 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) {
mbed_official 85:e1a8e879a6a9 218 int status, errorResult;
mbed_official 85:e1a8e879a6a9 219 obj->i2c->ADDRESS = (address>>1);
mbed_official 85:e1a8e879a6a9 220 obj->i2c->SHORTS = 0;
mbed_official 85:e1a8e879a6a9 221 obj->i2c->TASKS_STARTTX = 1;
mbed_official 85:e1a8e879a6a9 222
mbed_official 85:e1a8e879a6a9 223 for (int i=0; i<length; i++) {
mbed_official 85:e1a8e879a6a9 224 status = i2c_do_write(obj, data[i]);
mbed_official 85:e1a8e879a6a9 225 if(status) {
mbed_official 85:e1a8e879a6a9 226 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 227 errorResult = checkError(obj);
mbed_official 85:e1a8e879a6a9 228 if(errorResult<0){
mbed_official 85:e1a8e879a6a9 229 return errorResult;
mbed_official 85:e1a8e879a6a9 230 }
mbed_official 85:e1a8e879a6a9 231 return i;
mbed_official 85:e1a8e879a6a9 232 }
mbed_official 85:e1a8e879a6a9 233 }
mbed_official 85:e1a8e879a6a9 234
mbed_official 85:e1a8e879a6a9 235 // If not repeated start, send stop.
mbed_official 85:e1a8e879a6a9 236 if (stop) {
mbed_official 85:e1a8e879a6a9 237 if(i2c_stop(obj)){
mbed_official 85:e1a8e879a6a9 238 return I2C_ERROR_NO_SLAVE;
mbed_official 85:e1a8e879a6a9 239 }
mbed_official 85:e1a8e879a6a9 240 }
mbed_official 85:e1a8e879a6a9 241 return length;
mbed_official 85:e1a8e879a6a9 242 }
mbed_official 85:e1a8e879a6a9 243
mbed_official 85:e1a8e879a6a9 244 int i2c_byte_read(i2c_t *obj, int last) {
mbed_official 85:e1a8e879a6a9 245 char data;
mbed_official 85:e1a8e879a6a9 246 int status;
mbed_official 85:e1a8e879a6a9 247
mbed_official 85:e1a8e879a6a9 248 status = i2c_do_read(obj,&data, last);
mbed_official 85:e1a8e879a6a9 249 if (status) {
mbed_official 85:e1a8e879a6a9 250 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 251 }
mbed_official 85:e1a8e879a6a9 252 return data;
mbed_official 85:e1a8e879a6a9 253 }
mbed_official 85:e1a8e879a6a9 254
mbed_official 85:e1a8e879a6a9 255 int i2c_byte_write(i2c_t *obj, int data) {
mbed_official 85:e1a8e879a6a9 256 int status = 0;
mbed_official 85:e1a8e879a6a9 257 if(!addrSet){
mbed_official 85:e1a8e879a6a9 258 addrSet = 1;
mbed_official 85:e1a8e879a6a9 259 obj->i2c->ADDRESS = (data>>1);
mbed_official 85:e1a8e879a6a9 260
mbed_official 85:e1a8e879a6a9 261 if(data&1){
mbed_official 85:e1a8e879a6a9 262 obj->i2c->EVENTS_RXDREADY = 0;
mbed_official 85:e1a8e879a6a9 263 obj->i2c->TASKS_STARTRX = 1;
mbed_official 85:e1a8e879a6a9 264 }
mbed_official 85:e1a8e879a6a9 265 else{
mbed_official 85:e1a8e879a6a9 266 obj->i2c->TASKS_STARTTX = 1;
mbed_official 85:e1a8e879a6a9 267 }
mbed_official 85:e1a8e879a6a9 268 }
mbed_official 85:e1a8e879a6a9 269 else{
mbed_official 85:e1a8e879a6a9 270 status = i2c_do_write(obj, data);
mbed_official 85:e1a8e879a6a9 271 if(status) {
mbed_official 85:e1a8e879a6a9 272 i2c_reset(obj);
mbed_official 85:e1a8e879a6a9 273 }
mbed_official 85:e1a8e879a6a9 274 }
mbed_official 85:e1a8e879a6a9 275 return (1-status);
mbed_official 85:e1a8e879a6a9 276 }