MacroRat / MouseCode

Mouse code for the MacroRat

Dependencies:   ITG3200 QEI

mbed-dev/targets/TARGET_NXP/TARGET_LPC176X/i2c_api.c@18:6a4db94011d3, 2017-05-14 (annotated)

Committer:
sahilmgandhi
Date:
Sun May 14 23:18:57 2017 +0000
Revision:
18:6a4db94011d3
Publishing again

Who changed what in which revision?

UserRevisionLine numberNew contents of line
sahilmgandhi 18:6a4db94011d3 1 /* mbed Microcontroller Library
sahilmgandhi 18:6a4db94011d3 2 * Copyright (c) 2006-2013 ARM Limited
sahilmgandhi 18:6a4db94011d3 3 *
sahilmgandhi 18:6a4db94011d3 4 * Licensed under the Apache License, Version 2.0 (the "License");
sahilmgandhi 18:6a4db94011d3 5 * you may not use this file except in compliance with the License.
sahilmgandhi 18:6a4db94011d3 6 * You may obtain a copy of the License at
sahilmgandhi 18:6a4db94011d3 7 *
sahilmgandhi 18:6a4db94011d3 8 * http://www.apache.org/licenses/LICENSE-2.0
sahilmgandhi 18:6a4db94011d3 9 *
sahilmgandhi 18:6a4db94011d3 10 * Unless required by applicable law or agreed to in writing, software
sahilmgandhi 18:6a4db94011d3 11 * distributed under the License is distributed on an "AS IS" BASIS,
sahilmgandhi 18:6a4db94011d3 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
sahilmgandhi 18:6a4db94011d3 13 * See the License for the specific language governing permissions and
sahilmgandhi 18:6a4db94011d3 14 * limitations under the License.
sahilmgandhi 18:6a4db94011d3 15 */
sahilmgandhi 18:6a4db94011d3 16 #include "mbed_assert.h"
sahilmgandhi 18:6a4db94011d3 17 #include "i2c_api.h"
sahilmgandhi 18:6a4db94011d3 18 #include "cmsis.h"
sahilmgandhi 18:6a4db94011d3 19 #include "pinmap.h"
sahilmgandhi 18:6a4db94011d3 20
sahilmgandhi 18:6a4db94011d3 21 static const PinMap PinMap_I2C_SDA[] = {
sahilmgandhi 18:6a4db94011d3 22 {P0_0 , I2C_1, 3},
sahilmgandhi 18:6a4db94011d3 23 {P0_10, I2C_2, 2},
sahilmgandhi 18:6a4db94011d3 24 {P0_19, I2C_1, 3},
sahilmgandhi 18:6a4db94011d3 25 {P0_27, I2C_0, 1},
sahilmgandhi 18:6a4db94011d3 26 {NC , NC , 0}
sahilmgandhi 18:6a4db94011d3 27 };
sahilmgandhi 18:6a4db94011d3 28
sahilmgandhi 18:6a4db94011d3 29 static const PinMap PinMap_I2C_SCL[] = {
sahilmgandhi 18:6a4db94011d3 30 {P0_1 , I2C_1, 3},
sahilmgandhi 18:6a4db94011d3 31 {P0_11, I2C_2, 2},
sahilmgandhi 18:6a4db94011d3 32 {P0_20, I2C_1, 3},
sahilmgandhi 18:6a4db94011d3 33 {P0_28, I2C_0, 1},
sahilmgandhi 18:6a4db94011d3 34 {NC , NC, 0}
sahilmgandhi 18:6a4db94011d3 35 };
sahilmgandhi 18:6a4db94011d3 36
sahilmgandhi 18:6a4db94011d3 37 #define I2C_CONSET(x) (x->i2c->I2CONSET)
sahilmgandhi 18:6a4db94011d3 38 #define I2C_CONCLR(x) (x->i2c->I2CONCLR)
sahilmgandhi 18:6a4db94011d3 39 #define I2C_STAT(x) (x->i2c->I2STAT)
sahilmgandhi 18:6a4db94011d3 40 #define I2C_DAT(x) (x->i2c->I2DAT)
sahilmgandhi 18:6a4db94011d3 41 #define I2C_SCLL(x, val) (x->i2c->I2SCLL = val)
sahilmgandhi 18:6a4db94011d3 42 #define I2C_SCLH(x, val) (x->i2c->I2SCLH = val)
sahilmgandhi 18:6a4db94011d3 43
sahilmgandhi 18:6a4db94011d3 44 static const uint32_t I2C_addr_offset[2][4] = {
sahilmgandhi 18:6a4db94011d3 45 {0x0C, 0x20, 0x24, 0x28},
sahilmgandhi 18:6a4db94011d3 46 {0x30, 0x34, 0x38, 0x3C}
sahilmgandhi 18:6a4db94011d3 47 };
sahilmgandhi 18:6a4db94011d3 48
sahilmgandhi 18:6a4db94011d3 49 static inline void i2c_conclr(i2c_t *obj, int start, int stop, int interrupt, int acknowledge) {
sahilmgandhi 18:6a4db94011d3 50 I2C_CONCLR(obj) = (start << 5)
sahilmgandhi 18:6a4db94011d3 51 | (stop << 4)
sahilmgandhi 18:6a4db94011d3 52 | (interrupt << 3)
sahilmgandhi 18:6a4db94011d3 53 | (acknowledge << 2);
sahilmgandhi 18:6a4db94011d3 54 }
sahilmgandhi 18:6a4db94011d3 55
sahilmgandhi 18:6a4db94011d3 56 static inline void i2c_conset(i2c_t *obj, int start, int stop, int interrupt, int acknowledge) {
sahilmgandhi 18:6a4db94011d3 57 I2C_CONSET(obj) = (start << 5)
sahilmgandhi 18:6a4db94011d3 58 | (stop << 4)
sahilmgandhi 18:6a4db94011d3 59 | (interrupt << 3)
sahilmgandhi 18:6a4db94011d3 60 | (acknowledge << 2);
sahilmgandhi 18:6a4db94011d3 61 }
sahilmgandhi 18:6a4db94011d3 62
sahilmgandhi 18:6a4db94011d3 63 // Clear the Serial Interrupt (SI)
sahilmgandhi 18:6a4db94011d3 64 static inline void i2c_clear_SI(i2c_t *obj) {
sahilmgandhi 18:6a4db94011d3 65 i2c_conclr(obj, 0, 0, 1, 0);
sahilmgandhi 18:6a4db94011d3 66 }
sahilmgandhi 18:6a4db94011d3 67
sahilmgandhi 18:6a4db94011d3 68 static inline int i2c_status(i2c_t *obj) {
sahilmgandhi 18:6a4db94011d3 69 return I2C_STAT(obj);
sahilmgandhi 18:6a4db94011d3 70 }
sahilmgandhi 18:6a4db94011d3 71
sahilmgandhi 18:6a4db94011d3 72 // Wait until the Serial Interrupt (SI) is set
sahilmgandhi 18:6a4db94011d3 73 static int i2c_wait_SI(i2c_t *obj) {
sahilmgandhi 18:6a4db94011d3 74 int timeout = 0;
sahilmgandhi 18:6a4db94011d3 75 while (!(I2C_CONSET(obj) & (1 << 3))) {
sahilmgandhi 18:6a4db94011d3 76 timeout++;
sahilmgandhi 18:6a4db94011d3 77 if (timeout > 100000) return -1;
sahilmgandhi 18:6a4db94011d3 78 }
sahilmgandhi 18:6a4db94011d3 79 return 0;
sahilmgandhi 18:6a4db94011d3 80 }
sahilmgandhi 18:6a4db94011d3 81
sahilmgandhi 18:6a4db94011d3 82 static inline void i2c_interface_enable(i2c_t *obj) {
sahilmgandhi 18:6a4db94011d3 83 I2C_CONSET(obj) = 0x40;
sahilmgandhi 18:6a4db94011d3 84 }
sahilmgandhi 18:6a4db94011d3 85
sahilmgandhi 18:6a4db94011d3 86 static inline void i2c_power_enable(i2c_t *obj) {
sahilmgandhi 18:6a4db94011d3 87 switch ((int)obj->i2c) {
sahilmgandhi 18:6a4db94011d3 88 case I2C_0: LPC_SC->PCONP |= 1 << 7; break;
sahilmgandhi 18:6a4db94011d3 89 case I2C_1: LPC_SC->PCONP |= 1 << 19; break;
sahilmgandhi 18:6a4db94011d3 90 case I2C_2: LPC_SC->PCONP |= 1 << 26; break;
sahilmgandhi 18:6a4db94011d3 91 }
sahilmgandhi 18:6a4db94011d3 92 }
sahilmgandhi 18:6a4db94011d3 93
sahilmgandhi 18:6a4db94011d3 94 void i2c_init(i2c_t *obj, PinName sda, PinName scl) {
sahilmgandhi 18:6a4db94011d3 95 // determine the SPI to use
sahilmgandhi 18:6a4db94011d3 96 I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA);
sahilmgandhi 18:6a4db94011d3 97 I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL);
sahilmgandhi 18:6a4db94011d3 98 obj->i2c = (LPC_I2C_TypeDef *)pinmap_merge(i2c_sda, i2c_scl);
sahilmgandhi 18:6a4db94011d3 99 MBED_ASSERT((int)obj->i2c != NC);
sahilmgandhi 18:6a4db94011d3 100
sahilmgandhi 18:6a4db94011d3 101 // enable power
sahilmgandhi 18:6a4db94011d3 102 i2c_power_enable(obj);
sahilmgandhi 18:6a4db94011d3 103
sahilmgandhi 18:6a4db94011d3 104 // set default frequency at 100k
sahilmgandhi 18:6a4db94011d3 105 i2c_frequency(obj, 100000);
sahilmgandhi 18:6a4db94011d3 106 i2c_conclr(obj, 1, 1, 1, 1);
sahilmgandhi 18:6a4db94011d3 107 i2c_interface_enable(obj);
sahilmgandhi 18:6a4db94011d3 108
sahilmgandhi 18:6a4db94011d3 109 pinmap_pinout(sda, PinMap_I2C_SDA);
sahilmgandhi 18:6a4db94011d3 110 pinmap_pinout(scl, PinMap_I2C_SCL);
sahilmgandhi 18:6a4db94011d3 111 }
sahilmgandhi 18:6a4db94011d3 112
sahilmgandhi 18:6a4db94011d3 113 inline int i2c_start(i2c_t *obj) {
sahilmgandhi 18:6a4db94011d3 114 int status = 0;
sahilmgandhi 18:6a4db94011d3 115 int isInterrupted = I2C_CONSET(obj) & (1 << 3);
sahilmgandhi 18:6a4db94011d3 116
sahilmgandhi 18:6a4db94011d3 117 // 8.1 Before master mode can be entered, I2CON must be initialised to:
sahilmgandhi 18:6a4db94011d3 118 // - I2EN STA STO SI AA - -
sahilmgandhi 18:6a4db94011d3 119 // - 1 0 0 x x - -
sahilmgandhi 18:6a4db94011d3 120 // if AA = 0, it can't enter slave mode
sahilmgandhi 18:6a4db94011d3 121 i2c_conclr(obj, 1, 1, 0, 1);
sahilmgandhi 18:6a4db94011d3 122
sahilmgandhi 18:6a4db94011d3 123 // The master mode may now be entered by setting the STA bit
sahilmgandhi 18:6a4db94011d3 124 // this will generate a start condition when the bus becomes free
sahilmgandhi 18:6a4db94011d3 125 i2c_conset(obj, 1, 0, 0, 1);
sahilmgandhi 18:6a4db94011d3 126 // Clearing SI bit when it wasn't set on entry can jump past state
sahilmgandhi 18:6a4db94011d3 127 // 0x10 or 0x08 and erroneously send uninitialized slave address.
sahilmgandhi 18:6a4db94011d3 128 if (isInterrupted)
sahilmgandhi 18:6a4db94011d3 129 i2c_clear_SI(obj);
sahilmgandhi 18:6a4db94011d3 130
sahilmgandhi 18:6a4db94011d3 131 i2c_wait_SI(obj);
sahilmgandhi 18:6a4db94011d3 132 status = i2c_status(obj);
sahilmgandhi 18:6a4db94011d3 133
sahilmgandhi 18:6a4db94011d3 134 // Clear start bit now that it's transmitted
sahilmgandhi 18:6a4db94011d3 135 i2c_conclr(obj, 1, 0, 0, 0);
sahilmgandhi 18:6a4db94011d3 136 return status;
sahilmgandhi 18:6a4db94011d3 137 }
sahilmgandhi 18:6a4db94011d3 138
sahilmgandhi 18:6a4db94011d3 139 inline int i2c_stop(i2c_t *obj) {
sahilmgandhi 18:6a4db94011d3 140 int timeout = 0;
sahilmgandhi 18:6a4db94011d3 141
sahilmgandhi 18:6a4db94011d3 142 // write the stop bit
sahilmgandhi 18:6a4db94011d3 143 i2c_conset(obj, 0, 1, 0, 0);
sahilmgandhi 18:6a4db94011d3 144 i2c_clear_SI(obj);
sahilmgandhi 18:6a4db94011d3 145
sahilmgandhi 18:6a4db94011d3 146 // wait for STO bit to reset
sahilmgandhi 18:6a4db94011d3 147 while(I2C_CONSET(obj) & (1 << 4)) {
sahilmgandhi 18:6a4db94011d3 148 timeout ++;
sahilmgandhi 18:6a4db94011d3 149 if (timeout > 100000) return 1;
sahilmgandhi 18:6a4db94011d3 150 }
sahilmgandhi 18:6a4db94011d3 151
sahilmgandhi 18:6a4db94011d3 152 return 0;
sahilmgandhi 18:6a4db94011d3 153 }
sahilmgandhi 18:6a4db94011d3 154
sahilmgandhi 18:6a4db94011d3 155 static inline int i2c_do_write(i2c_t *obj, int value, uint8_t addr) {
sahilmgandhi 18:6a4db94011d3 156 // write the data
sahilmgandhi 18:6a4db94011d3 157 I2C_DAT(obj) = value;
sahilmgandhi 18:6a4db94011d3 158
sahilmgandhi 18:6a4db94011d3 159 // clear SI to init a send
sahilmgandhi 18:6a4db94011d3 160 i2c_clear_SI(obj);
sahilmgandhi 18:6a4db94011d3 161
sahilmgandhi 18:6a4db94011d3 162 // wait and return status
sahilmgandhi 18:6a4db94011d3 163 i2c_wait_SI(obj);
sahilmgandhi 18:6a4db94011d3 164 return i2c_status(obj);
sahilmgandhi 18:6a4db94011d3 165 }
sahilmgandhi 18:6a4db94011d3 166
sahilmgandhi 18:6a4db94011d3 167 static inline int i2c_do_read(i2c_t *obj, int last) {
sahilmgandhi 18:6a4db94011d3 168 // we are in state 0x40 (SLA+R tx'd) or 0x50 (data rx'd and ack)
sahilmgandhi 18:6a4db94011d3 169 if(last) {
sahilmgandhi 18:6a4db94011d3 170 i2c_conclr(obj, 0, 0, 0, 1); // send a NOT ACK
sahilmgandhi 18:6a4db94011d3 171 } else {
sahilmgandhi 18:6a4db94011d3 172 i2c_conset(obj, 0, 0, 0, 1); // send a ACK
sahilmgandhi 18:6a4db94011d3 173 }
sahilmgandhi 18:6a4db94011d3 174
sahilmgandhi 18:6a4db94011d3 175 // accept byte
sahilmgandhi 18:6a4db94011d3 176 i2c_clear_SI(obj);
sahilmgandhi 18:6a4db94011d3 177
sahilmgandhi 18:6a4db94011d3 178 // wait for it to arrive
sahilmgandhi 18:6a4db94011d3 179 i2c_wait_SI(obj);
sahilmgandhi 18:6a4db94011d3 180
sahilmgandhi 18:6a4db94011d3 181 // return the data
sahilmgandhi 18:6a4db94011d3 182 return (I2C_DAT(obj) & 0xFF);
sahilmgandhi 18:6a4db94011d3 183 }
sahilmgandhi 18:6a4db94011d3 184
sahilmgandhi 18:6a4db94011d3 185 void i2c_frequency(i2c_t *obj, int hz) {
sahilmgandhi 18:6a4db94011d3 186 // [TODO] set pclk to /4
sahilmgandhi 18:6a4db94011d3 187 uint32_t PCLK = SystemCoreClock / 4;
sahilmgandhi 18:6a4db94011d3 188
sahilmgandhi 18:6a4db94011d3 189 uint32_t pulse = PCLK / (hz * 2);
sahilmgandhi 18:6a4db94011d3 190
sahilmgandhi 18:6a4db94011d3 191 // I2C Rate
sahilmgandhi 18:6a4db94011d3 192 I2C_SCLL(obj, pulse);
sahilmgandhi 18:6a4db94011d3 193 I2C_SCLH(obj, pulse);
sahilmgandhi 18:6a4db94011d3 194 }
sahilmgandhi 18:6a4db94011d3 195
sahilmgandhi 18:6a4db94011d3 196 // The I2C does a read or a write as a whole operation
sahilmgandhi 18:6a4db94011d3 197 // There are two types of error conditions it can encounter
sahilmgandhi 18:6a4db94011d3 198 // 1) it can not obtain the bus
sahilmgandhi 18:6a4db94011d3 199 // 2) it gets error responses at part of the transmission
sahilmgandhi 18:6a4db94011d3 200 //
sahilmgandhi 18:6a4db94011d3 201 // We tackle them as follows:
sahilmgandhi 18:6a4db94011d3 202 // 1) we retry until we get the bus. we could have a "timeout" if we can not get it
sahilmgandhi 18:6a4db94011d3 203 // which basically turns it in to a 2)
sahilmgandhi 18:6a4db94011d3 204 // 2) on error, we use the standard error mechanisms to report/debug
sahilmgandhi 18:6a4db94011d3 205 //
sahilmgandhi 18:6a4db94011d3 206 // Therefore an I2C transaction should always complete. If it doesn't it is usually
sahilmgandhi 18:6a4db94011d3 207 // because something is setup wrong (e.g. wiring), and we don't need to programatically
sahilmgandhi 18:6a4db94011d3 208 // check for that
sahilmgandhi 18:6a4db94011d3 209
sahilmgandhi 18:6a4db94011d3 210 int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) {
sahilmgandhi 18:6a4db94011d3 211 int count, status;
sahilmgandhi 18:6a4db94011d3 212
sahilmgandhi 18:6a4db94011d3 213 status = i2c_start(obj);
sahilmgandhi 18:6a4db94011d3 214
sahilmgandhi 18:6a4db94011d3 215 if ((status != 0x10) && (status != 0x08)) {
sahilmgandhi 18:6a4db94011d3 216 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 217 return I2C_ERROR_BUS_BUSY;
sahilmgandhi 18:6a4db94011d3 218 }
sahilmgandhi 18:6a4db94011d3 219
sahilmgandhi 18:6a4db94011d3 220 status = i2c_do_write(obj, (address | 0x01), 1);
sahilmgandhi 18:6a4db94011d3 221 if (status != 0x40) {
sahilmgandhi 18:6a4db94011d3 222 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 223 return I2C_ERROR_NO_SLAVE;
sahilmgandhi 18:6a4db94011d3 224 }
sahilmgandhi 18:6a4db94011d3 225
sahilmgandhi 18:6a4db94011d3 226 // Read in all except last byte
sahilmgandhi 18:6a4db94011d3 227 for (count = 0; count < (length - 1); count++) {
sahilmgandhi 18:6a4db94011d3 228 int value = i2c_do_read(obj, 0);
sahilmgandhi 18:6a4db94011d3 229 status = i2c_status(obj);
sahilmgandhi 18:6a4db94011d3 230 if (status != 0x50) {
sahilmgandhi 18:6a4db94011d3 231 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 232 return count;
sahilmgandhi 18:6a4db94011d3 233 }
sahilmgandhi 18:6a4db94011d3 234 data[count] = (char) value;
sahilmgandhi 18:6a4db94011d3 235 }
sahilmgandhi 18:6a4db94011d3 236
sahilmgandhi 18:6a4db94011d3 237 // read in last byte
sahilmgandhi 18:6a4db94011d3 238 int value = i2c_do_read(obj, 1);
sahilmgandhi 18:6a4db94011d3 239 status = i2c_status(obj);
sahilmgandhi 18:6a4db94011d3 240 if (status != 0x58) {
sahilmgandhi 18:6a4db94011d3 241 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 242 return length - 1;
sahilmgandhi 18:6a4db94011d3 243 }
sahilmgandhi 18:6a4db94011d3 244
sahilmgandhi 18:6a4db94011d3 245 data[count] = (char) value;
sahilmgandhi 18:6a4db94011d3 246
sahilmgandhi 18:6a4db94011d3 247 // If not repeated start, send stop.
sahilmgandhi 18:6a4db94011d3 248 if (stop) {
sahilmgandhi 18:6a4db94011d3 249 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 250 }
sahilmgandhi 18:6a4db94011d3 251
sahilmgandhi 18:6a4db94011d3 252 return length;
sahilmgandhi 18:6a4db94011d3 253 }
sahilmgandhi 18:6a4db94011d3 254
sahilmgandhi 18:6a4db94011d3 255 int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) {
sahilmgandhi 18:6a4db94011d3 256 int i, status;
sahilmgandhi 18:6a4db94011d3 257
sahilmgandhi 18:6a4db94011d3 258 status = i2c_start(obj);
sahilmgandhi 18:6a4db94011d3 259
sahilmgandhi 18:6a4db94011d3 260 if ((status != 0x10) && (status != 0x08)) {
sahilmgandhi 18:6a4db94011d3 261 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 262 return I2C_ERROR_BUS_BUSY;
sahilmgandhi 18:6a4db94011d3 263 }
sahilmgandhi 18:6a4db94011d3 264
sahilmgandhi 18:6a4db94011d3 265 status = i2c_do_write(obj, (address & 0xFE), 1);
sahilmgandhi 18:6a4db94011d3 266 if (status != 0x18) {
sahilmgandhi 18:6a4db94011d3 267 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 268 return I2C_ERROR_NO_SLAVE;
sahilmgandhi 18:6a4db94011d3 269 }
sahilmgandhi 18:6a4db94011d3 270
sahilmgandhi 18:6a4db94011d3 271 for (i=0; i<length; i++) {
sahilmgandhi 18:6a4db94011d3 272 status = i2c_do_write(obj, data[i], 0);
sahilmgandhi 18:6a4db94011d3 273 if(status != 0x28) {
sahilmgandhi 18:6a4db94011d3 274 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 275 return i;
sahilmgandhi 18:6a4db94011d3 276 }
sahilmgandhi 18:6a4db94011d3 277 }
sahilmgandhi 18:6a4db94011d3 278
sahilmgandhi 18:6a4db94011d3 279 // clearing the serial interrupt here might cause an unintended rewrite of the last byte
sahilmgandhi 18:6a4db94011d3 280 // see also issue report https://mbed.org/users/mbed_official/code/mbed/issues/1
sahilmgandhi 18:6a4db94011d3 281 // i2c_clear_SI(obj);
sahilmgandhi 18:6a4db94011d3 282
sahilmgandhi 18:6a4db94011d3 283 // If not repeated start, send stop.
sahilmgandhi 18:6a4db94011d3 284 if (stop) {
sahilmgandhi 18:6a4db94011d3 285 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 286 }
sahilmgandhi 18:6a4db94011d3 287
sahilmgandhi 18:6a4db94011d3 288 return length;
sahilmgandhi 18:6a4db94011d3 289 }
sahilmgandhi 18:6a4db94011d3 290
sahilmgandhi 18:6a4db94011d3 291 void i2c_reset(i2c_t *obj) {
sahilmgandhi 18:6a4db94011d3 292 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 293 }
sahilmgandhi 18:6a4db94011d3 294
sahilmgandhi 18:6a4db94011d3 295 int i2c_byte_read(i2c_t *obj, int last) {
sahilmgandhi 18:6a4db94011d3 296 return (i2c_do_read(obj, last) & 0xFF);
sahilmgandhi 18:6a4db94011d3 297 }
sahilmgandhi 18:6a4db94011d3 298
sahilmgandhi 18:6a4db94011d3 299 int i2c_byte_write(i2c_t *obj, int data) {
sahilmgandhi 18:6a4db94011d3 300 int ack;
sahilmgandhi 18:6a4db94011d3 301 int status = i2c_do_write(obj, (data & 0xFF), 0);
sahilmgandhi 18:6a4db94011d3 302
sahilmgandhi 18:6a4db94011d3 303 switch(status) {
sahilmgandhi 18:6a4db94011d3 304 case 0x18: case 0x28: // Master transmit ACKs
sahilmgandhi 18:6a4db94011d3 305 ack = 1;
sahilmgandhi 18:6a4db94011d3 306 break;
sahilmgandhi 18:6a4db94011d3 307 case 0x40: // Master receive address transmitted ACK
sahilmgandhi 18:6a4db94011d3 308 ack = 1;
sahilmgandhi 18:6a4db94011d3 309 break;
sahilmgandhi 18:6a4db94011d3 310 case 0xB8: // Slave transmit ACK
sahilmgandhi 18:6a4db94011d3 311 ack = 1;
sahilmgandhi 18:6a4db94011d3 312 break;
sahilmgandhi 18:6a4db94011d3 313 default:
sahilmgandhi 18:6a4db94011d3 314 ack = 0;
sahilmgandhi 18:6a4db94011d3 315 break;
sahilmgandhi 18:6a4db94011d3 316 }
sahilmgandhi 18:6a4db94011d3 317
sahilmgandhi 18:6a4db94011d3 318 return ack;
sahilmgandhi 18:6a4db94011d3 319 }
sahilmgandhi 18:6a4db94011d3 320
sahilmgandhi 18:6a4db94011d3 321 void i2c_slave_mode(i2c_t *obj, int enable_slave) {
sahilmgandhi 18:6a4db94011d3 322 if (enable_slave != 0) {
sahilmgandhi 18:6a4db94011d3 323 i2c_conclr(obj, 1, 1, 1, 0);
sahilmgandhi 18:6a4db94011d3 324 i2c_conset(obj, 0, 0, 0, 1);
sahilmgandhi 18:6a4db94011d3 325 } else {
sahilmgandhi 18:6a4db94011d3 326 i2c_conclr(obj, 1, 1, 1, 1);
sahilmgandhi 18:6a4db94011d3 327 }
sahilmgandhi 18:6a4db94011d3 328 }
sahilmgandhi 18:6a4db94011d3 329
sahilmgandhi 18:6a4db94011d3 330 int i2c_slave_receive(i2c_t *obj) {
sahilmgandhi 18:6a4db94011d3 331 int status;
sahilmgandhi 18:6a4db94011d3 332 int retval;
sahilmgandhi 18:6a4db94011d3 333
sahilmgandhi 18:6a4db94011d3 334 status = i2c_status(obj);
sahilmgandhi 18:6a4db94011d3 335 switch(status) {
sahilmgandhi 18:6a4db94011d3 336 case 0x60: retval = 3; break;
sahilmgandhi 18:6a4db94011d3 337 case 0x70: retval = 2; break;
sahilmgandhi 18:6a4db94011d3 338 case 0xA8: retval = 1; break;
sahilmgandhi 18:6a4db94011d3 339 default : retval = 0; break;
sahilmgandhi 18:6a4db94011d3 340 }
sahilmgandhi 18:6a4db94011d3 341
sahilmgandhi 18:6a4db94011d3 342 return(retval);
sahilmgandhi 18:6a4db94011d3 343 }
sahilmgandhi 18:6a4db94011d3 344
sahilmgandhi 18:6a4db94011d3 345 int i2c_slave_read(i2c_t *obj, char *data, int length) {
sahilmgandhi 18:6a4db94011d3 346 int count = 0;
sahilmgandhi 18:6a4db94011d3 347 int status;
sahilmgandhi 18:6a4db94011d3 348
sahilmgandhi 18:6a4db94011d3 349 do {
sahilmgandhi 18:6a4db94011d3 350 i2c_clear_SI(obj);
sahilmgandhi 18:6a4db94011d3 351 i2c_wait_SI(obj);
sahilmgandhi 18:6a4db94011d3 352 status = i2c_status(obj);
sahilmgandhi 18:6a4db94011d3 353 if((status == 0x80) || (status == 0x90)) {
sahilmgandhi 18:6a4db94011d3 354 data[count] = I2C_DAT(obj) & 0xFF;
sahilmgandhi 18:6a4db94011d3 355 }
sahilmgandhi 18:6a4db94011d3 356 count++;
sahilmgandhi 18:6a4db94011d3 357 } while (((status == 0x80) || (status == 0x90) ||
sahilmgandhi 18:6a4db94011d3 358 (status == 0x060) || (status == 0x70)) && (count < length));
sahilmgandhi 18:6a4db94011d3 359
sahilmgandhi 18:6a4db94011d3 360 // Clear old status and wait for Serial Interrupt.
sahilmgandhi 18:6a4db94011d3 361 i2c_clear_SI(obj);
sahilmgandhi 18:6a4db94011d3 362 i2c_wait_SI(obj);
sahilmgandhi 18:6a4db94011d3 363
sahilmgandhi 18:6a4db94011d3 364 // Obtain new status.
sahilmgandhi 18:6a4db94011d3 365 status = i2c_status(obj);
sahilmgandhi 18:6a4db94011d3 366
sahilmgandhi 18:6a4db94011d3 367 if(status != 0xA0) {
sahilmgandhi 18:6a4db94011d3 368 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 369 }
sahilmgandhi 18:6a4db94011d3 370
sahilmgandhi 18:6a4db94011d3 371 i2c_clear_SI(obj);
sahilmgandhi 18:6a4db94011d3 372
sahilmgandhi 18:6a4db94011d3 373 return count;
sahilmgandhi 18:6a4db94011d3 374 }
sahilmgandhi 18:6a4db94011d3 375
sahilmgandhi 18:6a4db94011d3 376 int i2c_slave_write(i2c_t *obj, const char *data, int length) {
sahilmgandhi 18:6a4db94011d3 377 int count = 0;
sahilmgandhi 18:6a4db94011d3 378 int status;
sahilmgandhi 18:6a4db94011d3 379
sahilmgandhi 18:6a4db94011d3 380 if(length <= 0) {
sahilmgandhi 18:6a4db94011d3 381 return(0);
sahilmgandhi 18:6a4db94011d3 382 }
sahilmgandhi 18:6a4db94011d3 383
sahilmgandhi 18:6a4db94011d3 384 do {
sahilmgandhi 18:6a4db94011d3 385 status = i2c_do_write(obj, data[count], 0);
sahilmgandhi 18:6a4db94011d3 386 count++;
sahilmgandhi 18:6a4db94011d3 387 } while ((count < length) && (status == 0xB8));
sahilmgandhi 18:6a4db94011d3 388
sahilmgandhi 18:6a4db94011d3 389 if ((status != 0xC0) && (status != 0xC8)) {
sahilmgandhi 18:6a4db94011d3 390 i2c_stop(obj);
sahilmgandhi 18:6a4db94011d3 391 }
sahilmgandhi 18:6a4db94011d3 392
sahilmgandhi 18:6a4db94011d3 393 i2c_clear_SI(obj);
sahilmgandhi 18:6a4db94011d3 394
sahilmgandhi 18:6a4db94011d3 395 return(count);
sahilmgandhi 18:6a4db94011d3 396 }
sahilmgandhi 18:6a4db94011d3 397
sahilmgandhi 18:6a4db94011d3 398 void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask) {
sahilmgandhi 18:6a4db94011d3 399 uint32_t addr;
sahilmgandhi 18:6a4db94011d3 400
sahilmgandhi 18:6a4db94011d3 401 if ((idx >= 0) && (idx <= 3)) {
sahilmgandhi 18:6a4db94011d3 402 addr = ((uint32_t)obj->i2c) + I2C_addr_offset[0][idx];
sahilmgandhi 18:6a4db94011d3 403 *((uint32_t *) addr) = address & 0xFF;
sahilmgandhi 18:6a4db94011d3 404 addr = ((uint32_t)obj->i2c) + I2C_addr_offset[1][idx];
sahilmgandhi 18:6a4db94011d3 405 *((uint32_t *) addr) = mask & 0xFE;
sahilmgandhi 18:6a4db94011d3 406 }
sahilmgandhi 18:6a4db94011d3 407 }