mbed library sources
Dependents: frdm_kl05z_gpio_test
Fork of mbed-src by
targets/hal/TARGET_NXP/TARGET_LPC23XX/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:
- 13:0645d8841f51
Synchronized with git revision d58d532ebc0e0a96f4fffb8edefc082b71b964af
Full URL: https://github.com/mbedmicro/mbed/commit/d58d532ebc0e0a96f4fffb8edefc082b71b964af/
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
bogdanm | 13:0645d8841f51 | 1 | /* mbed Microcontroller Library |
bogdanm | 13:0645d8841f51 | 2 | * Copyright (c) 2006-2013 ARM Limited |
bogdanm | 13:0645d8841f51 | 3 | * |
bogdanm | 13:0645d8841f51 | 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
bogdanm | 13:0645d8841f51 | 5 | * you may not use this file except in compliance with the License. |
bogdanm | 13:0645d8841f51 | 6 | * You may obtain a copy of the License at |
bogdanm | 13:0645d8841f51 | 7 | * |
bogdanm | 13:0645d8841f51 | 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
bogdanm | 13:0645d8841f51 | 9 | * |
bogdanm | 13:0645d8841f51 | 10 | * Unless required by applicable law or agreed to in writing, software |
bogdanm | 13:0645d8841f51 | 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
bogdanm | 13:0645d8841f51 | 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
bogdanm | 13:0645d8841f51 | 13 | * See the License for the specific language governing permissions and |
bogdanm | 13:0645d8841f51 | 14 | * limitations under the License. |
bogdanm | 13:0645d8841f51 | 15 | */ |
bogdanm | 13:0645d8841f51 | 16 | #include "i2c_api.h" |
bogdanm | 13:0645d8841f51 | 17 | #include "cmsis.h" |
bogdanm | 13:0645d8841f51 | 18 | #include "pinmap.h" |
bogdanm | 13:0645d8841f51 | 19 | |
bogdanm | 13:0645d8841f51 | 20 | static const PinMap PinMap_I2C_SDA[] = { |
bogdanm | 13:0645d8841f51 | 21 | {P0_0 , I2C_1, 3}, |
bogdanm | 13:0645d8841f51 | 22 | {P0_10, I2C_2, 2}, |
bogdanm | 13:0645d8841f51 | 23 | {P0_19, I2C_1, 3}, |
bogdanm | 13:0645d8841f51 | 24 | {P0_27, I2C_0, 1}, |
bogdanm | 13:0645d8841f51 | 25 | {NC , NC , 0} |
bogdanm | 13:0645d8841f51 | 26 | }; |
bogdanm | 13:0645d8841f51 | 27 | |
bogdanm | 13:0645d8841f51 | 28 | static const PinMap PinMap_I2C_SCL[] = { |
bogdanm | 13:0645d8841f51 | 29 | {P0_1 , I2C_1, 3}, |
bogdanm | 13:0645d8841f51 | 30 | {P0_11, I2C_2, 2}, |
bogdanm | 13:0645d8841f51 | 31 | {P0_20, I2C_1, 3}, |
bogdanm | 13:0645d8841f51 | 32 | {P0_28, I2C_0, 1}, |
bogdanm | 13:0645d8841f51 | 33 | {NC , NC, 0} |
bogdanm | 13:0645d8841f51 | 34 | }; |
bogdanm | 13:0645d8841f51 | 35 | |
bogdanm | 13:0645d8841f51 | 36 | #define I2C_CONSET(x) (x->i2c->I2CONSET) |
bogdanm | 13:0645d8841f51 | 37 | #define I2C_CONCLR(x) (x->i2c->I2CONCLR) |
bogdanm | 13:0645d8841f51 | 38 | #define I2C_STAT(x) (x->i2c->I2STAT) |
bogdanm | 13:0645d8841f51 | 39 | #define I2C_DAT(x) (x->i2c->I2DAT) |
bogdanm | 13:0645d8841f51 | 40 | #define I2C_SCLL(x, val) (x->i2c->I2SCLL = val) |
bogdanm | 13:0645d8841f51 | 41 | #define I2C_SCLH(x, val) (x->i2c->I2SCLH = val) |
bogdanm | 13:0645d8841f51 | 42 | |
bogdanm | 13:0645d8841f51 | 43 | static const uint32_t I2C_addr_offset[2][4] = { |
bogdanm | 13:0645d8841f51 | 44 | {0x0C, 0x20, 0x24, 0x28}, |
bogdanm | 13:0645d8841f51 | 45 | {0x30, 0x34, 0x38, 0x3C} |
bogdanm | 13:0645d8841f51 | 46 | }; |
bogdanm | 13:0645d8841f51 | 47 | |
bogdanm | 13:0645d8841f51 | 48 | static inline void i2c_conclr(i2c_t *obj, int start, int stop, int interrupt, int acknowledge) { |
bogdanm | 13:0645d8841f51 | 49 | I2C_CONCLR(obj) = (start << 5) |
bogdanm | 13:0645d8841f51 | 50 | | (stop << 4) |
bogdanm | 13:0645d8841f51 | 51 | | (interrupt << 3) |
bogdanm | 13:0645d8841f51 | 52 | | (acknowledge << 2); |
bogdanm | 13:0645d8841f51 | 53 | } |
bogdanm | 13:0645d8841f51 | 54 | |
bogdanm | 13:0645d8841f51 | 55 | static inline void i2c_conset(i2c_t *obj, int start, int stop, int interrupt, int acknowledge) { |
bogdanm | 13:0645d8841f51 | 56 | I2C_CONSET(obj) = (start << 5) |
bogdanm | 13:0645d8841f51 | 57 | | (stop << 4) |
bogdanm | 13:0645d8841f51 | 58 | | (interrupt << 3) |
bogdanm | 13:0645d8841f51 | 59 | | (acknowledge << 2); |
bogdanm | 13:0645d8841f51 | 60 | } |
bogdanm | 13:0645d8841f51 | 61 | |
bogdanm | 13:0645d8841f51 | 62 | // Clear the Serial Interrupt (SI) |
bogdanm | 13:0645d8841f51 | 63 | static inline void i2c_clear_SI(i2c_t *obj) { |
bogdanm | 13:0645d8841f51 | 64 | i2c_conclr(obj, 0, 0, 1, 0); |
bogdanm | 13:0645d8841f51 | 65 | } |
bogdanm | 13:0645d8841f51 | 66 | |
bogdanm | 13:0645d8841f51 | 67 | static inline int i2c_status(i2c_t *obj) { |
bogdanm | 13:0645d8841f51 | 68 | return I2C_STAT(obj); |
bogdanm | 13:0645d8841f51 | 69 | } |
bogdanm | 13:0645d8841f51 | 70 | |
bogdanm | 13:0645d8841f51 | 71 | // Wait until the Serial Interrupt (SI) is set |
bogdanm | 13:0645d8841f51 | 72 | static int i2c_wait_SI(i2c_t *obj) { |
bogdanm | 13:0645d8841f51 | 73 | int timeout = 0; |
bogdanm | 13:0645d8841f51 | 74 | while (!(I2C_CONSET(obj) & (1 << 3))) { |
bogdanm | 13:0645d8841f51 | 75 | timeout++; |
bogdanm | 13:0645d8841f51 | 76 | if (timeout > 100000) return -1; |
bogdanm | 13:0645d8841f51 | 77 | } |
bogdanm | 13:0645d8841f51 | 78 | return 0; |
bogdanm | 13:0645d8841f51 | 79 | } |
bogdanm | 13:0645d8841f51 | 80 | |
bogdanm | 13:0645d8841f51 | 81 | static inline void i2c_interface_enable(i2c_t *obj) { |
bogdanm | 13:0645d8841f51 | 82 | I2C_CONSET(obj) = 0x40; |
bogdanm | 13:0645d8841f51 | 83 | } |
bogdanm | 13:0645d8841f51 | 84 | |
bogdanm | 13:0645d8841f51 | 85 | static inline void i2c_power_enable(i2c_t *obj) { |
bogdanm | 13:0645d8841f51 | 86 | switch ((int)obj->i2c) { |
bogdanm | 13:0645d8841f51 | 87 | case I2C_0: LPC_SC->PCONP |= 1 << 7; break; |
bogdanm | 13:0645d8841f51 | 88 | case I2C_1: LPC_SC->PCONP |= 1 << 19; break; |
bogdanm | 13:0645d8841f51 | 89 | case I2C_2: LPC_SC->PCONP |= 1 << 26; break; |
bogdanm | 13:0645d8841f51 | 90 | } |
bogdanm | 13:0645d8841f51 | 91 | } |
bogdanm | 13:0645d8841f51 | 92 | |
bogdanm | 13:0645d8841f51 | 93 | void i2c_init(i2c_t *obj, PinName sda, PinName scl) { |
bogdanm | 13:0645d8841f51 | 94 | // determine the SPI to use |
bogdanm | 13:0645d8841f51 | 95 | I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA); |
bogdanm | 13:0645d8841f51 | 96 | I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL); |
bogdanm | 13:0645d8841f51 | 97 | obj->i2c = (LPC_I2C_TypeDef *)pinmap_merge(i2c_sda, i2c_scl); |
mbed_official | 227:7bd0639b8911 | 98 | MBED_ASSERT((int)obj->i2c != NC); |
bogdanm | 13:0645d8841f51 | 99 | |
bogdanm | 13:0645d8841f51 | 100 | // enable power |
bogdanm | 13:0645d8841f51 | 101 | i2c_power_enable(obj); |
bogdanm | 13:0645d8841f51 | 102 | |
bogdanm | 13:0645d8841f51 | 103 | // set default frequency at 100k |
bogdanm | 13:0645d8841f51 | 104 | i2c_frequency(obj, 100000); |
bogdanm | 13:0645d8841f51 | 105 | i2c_conclr(obj, 1, 1, 1, 1); |
bogdanm | 13:0645d8841f51 | 106 | i2c_interface_enable(obj); |
bogdanm | 13:0645d8841f51 | 107 | |
bogdanm | 13:0645d8841f51 | 108 | pinmap_pinout(sda, PinMap_I2C_SDA); |
bogdanm | 13:0645d8841f51 | 109 | pinmap_pinout(scl, PinMap_I2C_SCL); |
bogdanm | 13:0645d8841f51 | 110 | } |
bogdanm | 13:0645d8841f51 | 111 | |
bogdanm | 13:0645d8841f51 | 112 | inline int i2c_start(i2c_t *obj) { |
bogdanm | 13:0645d8841f51 | 113 | int status = 0; |
bogdanm | 13:0645d8841f51 | 114 | // 8.1 Before master mode can be entered, I2CON must be initialised to: |
bogdanm | 13:0645d8841f51 | 115 | // - I2EN STA STO SI AA - - |
bogdanm | 13:0645d8841f51 | 116 | // - 1 0 0 0 x - - |
bogdanm | 13:0645d8841f51 | 117 | // if AA = 0, it can't enter slave mode |
bogdanm | 13:0645d8841f51 | 118 | i2c_conclr(obj, 1, 1, 1, 1); |
bogdanm | 13:0645d8841f51 | 119 | |
bogdanm | 13:0645d8841f51 | 120 | // The master mode may now be entered by setting the STA bit |
bogdanm | 13:0645d8841f51 | 121 | // this will generate a start condition when the bus becomes free |
bogdanm | 13:0645d8841f51 | 122 | i2c_conset(obj, 1, 0, 0, 1); |
bogdanm | 13:0645d8841f51 | 123 | |
bogdanm | 13:0645d8841f51 | 124 | i2c_wait_SI(obj); |
bogdanm | 13:0645d8841f51 | 125 | status = i2c_status(obj); |
bogdanm | 13:0645d8841f51 | 126 | |
bogdanm | 13:0645d8841f51 | 127 | // Clear start bit now transmitted, and interrupt bit |
bogdanm | 13:0645d8841f51 | 128 | i2c_conclr(obj, 1, 0, 0, 0); |
bogdanm | 13:0645d8841f51 | 129 | return status; |
bogdanm | 13:0645d8841f51 | 130 | } |
bogdanm | 13:0645d8841f51 | 131 | |
bogdanm | 13:0645d8841f51 | 132 | inline int i2c_stop(i2c_t *obj) { |
bogdanm | 13:0645d8841f51 | 133 | int timeout = 0; |
bogdanm | 13:0645d8841f51 | 134 | |
bogdanm | 13:0645d8841f51 | 135 | // write the stop bit |
bogdanm | 13:0645d8841f51 | 136 | i2c_conset(obj, 0, 1, 0, 0); |
bogdanm | 13:0645d8841f51 | 137 | i2c_clear_SI(obj); |
bogdanm | 13:0645d8841f51 | 138 | |
bogdanm | 13:0645d8841f51 | 139 | // wait for STO bit to reset |
bogdanm | 13:0645d8841f51 | 140 | while (I2C_CONSET(obj) & (1 << 4)) { |
bogdanm | 13:0645d8841f51 | 141 | timeout ++; |
bogdanm | 13:0645d8841f51 | 142 | if (timeout > 100000) return 1; |
bogdanm | 13:0645d8841f51 | 143 | } |
bogdanm | 13:0645d8841f51 | 144 | |
bogdanm | 13:0645d8841f51 | 145 | return 0; |
bogdanm | 13:0645d8841f51 | 146 | } |
bogdanm | 13:0645d8841f51 | 147 | |
bogdanm | 13:0645d8841f51 | 148 | static inline int i2c_do_write(i2c_t *obj, int value, uint8_t addr) { |
bogdanm | 13:0645d8841f51 | 149 | // write the data |
bogdanm | 13:0645d8841f51 | 150 | I2C_DAT(obj) = value; |
bogdanm | 13:0645d8841f51 | 151 | |
bogdanm | 13:0645d8841f51 | 152 | // clear SI to init a send |
bogdanm | 13:0645d8841f51 | 153 | i2c_clear_SI(obj); |
bogdanm | 13:0645d8841f51 | 154 | |
bogdanm | 13:0645d8841f51 | 155 | // wait and return status |
bogdanm | 13:0645d8841f51 | 156 | i2c_wait_SI(obj); |
bogdanm | 13:0645d8841f51 | 157 | return i2c_status(obj); |
bogdanm | 13:0645d8841f51 | 158 | } |
bogdanm | 13:0645d8841f51 | 159 | |
bogdanm | 13:0645d8841f51 | 160 | static inline int i2c_do_read(i2c_t *obj, int last) { |
bogdanm | 13:0645d8841f51 | 161 | // we are in state 0x40 (SLA+R tx'd) or 0x50 (data rx'd and ack) |
bogdanm | 13:0645d8841f51 | 162 | if (last) { |
bogdanm | 13:0645d8841f51 | 163 | i2c_conclr(obj, 0, 0, 0, 1); // send a NOT ACK |
bogdanm | 13:0645d8841f51 | 164 | } else { |
bogdanm | 13:0645d8841f51 | 165 | i2c_conset(obj, 0, 0, 0, 1); // send a ACK |
bogdanm | 13:0645d8841f51 | 166 | } |
bogdanm | 13:0645d8841f51 | 167 | |
bogdanm | 13:0645d8841f51 | 168 | // accept byte |
bogdanm | 13:0645d8841f51 | 169 | i2c_clear_SI(obj); |
bogdanm | 13:0645d8841f51 | 170 | |
bogdanm | 13:0645d8841f51 | 171 | // wait for it to arrive |
bogdanm | 13:0645d8841f51 | 172 | i2c_wait_SI(obj); |
bogdanm | 13:0645d8841f51 | 173 | |
bogdanm | 13:0645d8841f51 | 174 | // return the data |
bogdanm | 13:0645d8841f51 | 175 | return (I2C_DAT(obj) & 0xFF); |
bogdanm | 13:0645d8841f51 | 176 | } |
bogdanm | 13:0645d8841f51 | 177 | |
bogdanm | 13:0645d8841f51 | 178 | void i2c_frequency(i2c_t *obj, int hz) { |
bogdanm | 13:0645d8841f51 | 179 | // [TODO] set pclk to /4 |
bogdanm | 13:0645d8841f51 | 180 | uint32_t PCLK = SystemCoreClock / 4; |
bogdanm | 13:0645d8841f51 | 181 | |
bogdanm | 13:0645d8841f51 | 182 | uint32_t pulse = PCLK / (hz * 2); |
bogdanm | 13:0645d8841f51 | 183 | |
bogdanm | 13:0645d8841f51 | 184 | // I2C Rate |
bogdanm | 13:0645d8841f51 | 185 | I2C_SCLL(obj, pulse); |
bogdanm | 13:0645d8841f51 | 186 | I2C_SCLH(obj, pulse); |
bogdanm | 13:0645d8841f51 | 187 | } |
bogdanm | 13:0645d8841f51 | 188 | |
bogdanm | 13:0645d8841f51 | 189 | // The I2C does a read or a write as a whole operation |
bogdanm | 13:0645d8841f51 | 190 | // There are two types of error conditions it can encounter |
bogdanm | 13:0645d8841f51 | 191 | // 1) it can not obtain the bus |
bogdanm | 13:0645d8841f51 | 192 | // 2) it gets error responses at part of the transmission |
bogdanm | 13:0645d8841f51 | 193 | // |
bogdanm | 13:0645d8841f51 | 194 | // We tackle them as follows: |
bogdanm | 13:0645d8841f51 | 195 | // 1) we retry until we get the bus. we could have a "timeout" if we can not get it |
bogdanm | 13:0645d8841f51 | 196 | // which basically turns it in to a 2) |
bogdanm | 13:0645d8841f51 | 197 | // 2) on error, we use the standard error mechanisms to report/debug |
bogdanm | 13:0645d8841f51 | 198 | // |
bogdanm | 13:0645d8841f51 | 199 | // Therefore an I2C transaction should always complete. If it doesn't it is usually |
bogdanm | 13:0645d8841f51 | 200 | // because something is setup wrong (e.g. wiring), and we don't need to programatically |
bogdanm | 13:0645d8841f51 | 201 | // check for that |
bogdanm | 13:0645d8841f51 | 202 | int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) { |
bogdanm | 13:0645d8841f51 | 203 | int count, status; |
bogdanm | 13:0645d8841f51 | 204 | |
bogdanm | 13:0645d8841f51 | 205 | status = i2c_start(obj); |
bogdanm | 13:0645d8841f51 | 206 | |
bogdanm | 13:0645d8841f51 | 207 | if ((status != 0x10) && (status != 0x08)) { |
bogdanm | 13:0645d8841f51 | 208 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 209 | return I2C_ERROR_BUS_BUSY; |
bogdanm | 13:0645d8841f51 | 210 | } |
bogdanm | 13:0645d8841f51 | 211 | |
bogdanm | 13:0645d8841f51 | 212 | status = i2c_do_write(obj, (address | 0x01), 1); |
bogdanm | 13:0645d8841f51 | 213 | if (status != 0x40) { |
bogdanm | 13:0645d8841f51 | 214 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 215 | return I2C_ERROR_NO_SLAVE; |
bogdanm | 13:0645d8841f51 | 216 | } |
bogdanm | 13:0645d8841f51 | 217 | |
bogdanm | 13:0645d8841f51 | 218 | // Read in all except last byte |
bogdanm | 13:0645d8841f51 | 219 | for (count = 0; count < (length - 1); count++) { |
bogdanm | 13:0645d8841f51 | 220 | int value = i2c_do_read(obj, 0); |
bogdanm | 13:0645d8841f51 | 221 | status = i2c_status(obj); |
bogdanm | 13:0645d8841f51 | 222 | if (status != 0x50) { |
bogdanm | 13:0645d8841f51 | 223 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 224 | return count; |
bogdanm | 13:0645d8841f51 | 225 | } |
bogdanm | 13:0645d8841f51 | 226 | data[count] = (char) value; |
bogdanm | 13:0645d8841f51 | 227 | } |
bogdanm | 13:0645d8841f51 | 228 | |
bogdanm | 13:0645d8841f51 | 229 | // read in last byte |
bogdanm | 13:0645d8841f51 | 230 | int value = i2c_do_read(obj, 1); |
bogdanm | 13:0645d8841f51 | 231 | status = i2c_status(obj); |
bogdanm | 13:0645d8841f51 | 232 | if (status != 0x58) { |
bogdanm | 13:0645d8841f51 | 233 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 234 | return length - 1; |
bogdanm | 13:0645d8841f51 | 235 | } |
bogdanm | 13:0645d8841f51 | 236 | |
bogdanm | 13:0645d8841f51 | 237 | data[count] = (char) value; |
bogdanm | 13:0645d8841f51 | 238 | |
bogdanm | 13:0645d8841f51 | 239 | // If not repeated start, send stop. |
bogdanm | 13:0645d8841f51 | 240 | if (stop) { |
bogdanm | 13:0645d8841f51 | 241 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 242 | } |
bogdanm | 13:0645d8841f51 | 243 | |
bogdanm | 13:0645d8841f51 | 244 | return length; |
bogdanm | 13:0645d8841f51 | 245 | } |
bogdanm | 13:0645d8841f51 | 246 | |
bogdanm | 13:0645d8841f51 | 247 | int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) { |
bogdanm | 13:0645d8841f51 | 248 | int i, status; |
bogdanm | 13:0645d8841f51 | 249 | |
bogdanm | 13:0645d8841f51 | 250 | status = i2c_start(obj); |
bogdanm | 13:0645d8841f51 | 251 | |
bogdanm | 13:0645d8841f51 | 252 | if ((status != 0x10) && (status != 0x08)) { |
bogdanm | 13:0645d8841f51 | 253 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 254 | return I2C_ERROR_BUS_BUSY; |
bogdanm | 13:0645d8841f51 | 255 | } |
bogdanm | 13:0645d8841f51 | 256 | |
bogdanm | 13:0645d8841f51 | 257 | status = i2c_do_write(obj, (address & 0xFE), 1); |
bogdanm | 13:0645d8841f51 | 258 | if (status != 0x18) { |
bogdanm | 13:0645d8841f51 | 259 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 260 | return I2C_ERROR_NO_SLAVE; |
bogdanm | 13:0645d8841f51 | 261 | } |
bogdanm | 13:0645d8841f51 | 262 | |
bogdanm | 13:0645d8841f51 | 263 | for (i=0; i<length; i++) { |
bogdanm | 13:0645d8841f51 | 264 | status = i2c_do_write(obj, data[i], 0); |
bogdanm | 13:0645d8841f51 | 265 | if (status != 0x28) { |
bogdanm | 13:0645d8841f51 | 266 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 267 | return i; |
bogdanm | 13:0645d8841f51 | 268 | } |
bogdanm | 13:0645d8841f51 | 269 | } |
bogdanm | 13:0645d8841f51 | 270 | |
bogdanm | 13:0645d8841f51 | 271 | // clearing the serial interrupt here might cause an unintended rewrite of the last byte |
bogdanm | 13:0645d8841f51 | 272 | // see also issue report https://mbed.org/users/mbed_official/code/mbed/issues/1 |
bogdanm | 13:0645d8841f51 | 273 | // i2c_clear_SI(obj); |
bogdanm | 13:0645d8841f51 | 274 | |
bogdanm | 13:0645d8841f51 | 275 | // If not repeated start, send stop. |
bogdanm | 13:0645d8841f51 | 276 | if (stop) { |
bogdanm | 13:0645d8841f51 | 277 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 278 | } |
bogdanm | 13:0645d8841f51 | 279 | |
bogdanm | 13:0645d8841f51 | 280 | return length; |
bogdanm | 13:0645d8841f51 | 281 | } |
bogdanm | 13:0645d8841f51 | 282 | |
bogdanm | 13:0645d8841f51 | 283 | void i2c_reset(i2c_t *obj) { |
bogdanm | 13:0645d8841f51 | 284 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 285 | } |
bogdanm | 13:0645d8841f51 | 286 | |
bogdanm | 13:0645d8841f51 | 287 | int i2c_byte_read(i2c_t *obj, int last) { |
bogdanm | 13:0645d8841f51 | 288 | return (i2c_do_read(obj, last) & 0xFF); |
bogdanm | 13:0645d8841f51 | 289 | } |
bogdanm | 13:0645d8841f51 | 290 | |
bogdanm | 13:0645d8841f51 | 291 | int i2c_byte_write(i2c_t *obj, int data) { |
bogdanm | 13:0645d8841f51 | 292 | int ack; |
bogdanm | 13:0645d8841f51 | 293 | int status = i2c_do_write(obj, (data & 0xFF), 0); |
bogdanm | 13:0645d8841f51 | 294 | |
bogdanm | 13:0645d8841f51 | 295 | switch(status) { |
bogdanm | 13:0645d8841f51 | 296 | case 0x18: case 0x28: // Master transmit ACKs |
bogdanm | 13:0645d8841f51 | 297 | ack = 1; |
bogdanm | 13:0645d8841f51 | 298 | break; |
bogdanm | 13:0645d8841f51 | 299 | |
bogdanm | 13:0645d8841f51 | 300 | case 0x40: // Master receive address transmitted ACK |
bogdanm | 13:0645d8841f51 | 301 | ack = 1; |
bogdanm | 13:0645d8841f51 | 302 | break; |
bogdanm | 13:0645d8841f51 | 303 | |
bogdanm | 13:0645d8841f51 | 304 | case 0xB8: // Slave transmit ACK |
bogdanm | 13:0645d8841f51 | 305 | ack = 1; |
bogdanm | 13:0645d8841f51 | 306 | break; |
bogdanm | 13:0645d8841f51 | 307 | |
bogdanm | 13:0645d8841f51 | 308 | default: |
bogdanm | 13:0645d8841f51 | 309 | ack = 0; |
bogdanm | 13:0645d8841f51 | 310 | break; |
bogdanm | 13:0645d8841f51 | 311 | } |
bogdanm | 13:0645d8841f51 | 312 | |
bogdanm | 13:0645d8841f51 | 313 | return ack; |
bogdanm | 13:0645d8841f51 | 314 | } |
bogdanm | 13:0645d8841f51 | 315 | |
bogdanm | 13:0645d8841f51 | 316 | void i2c_slave_mode(i2c_t *obj, int enable_slave) { |
bogdanm | 13:0645d8841f51 | 317 | if (enable_slave != 0) { |
bogdanm | 13:0645d8841f51 | 318 | i2c_conclr(obj, 1, 1, 1, 0); |
bogdanm | 13:0645d8841f51 | 319 | i2c_conset(obj, 0, 0, 0, 1); |
bogdanm | 13:0645d8841f51 | 320 | } else { |
bogdanm | 13:0645d8841f51 | 321 | i2c_conclr(obj, 1, 1, 1, 1); |
bogdanm | 13:0645d8841f51 | 322 | } |
bogdanm | 13:0645d8841f51 | 323 | } |
bogdanm | 13:0645d8841f51 | 324 | |
bogdanm | 13:0645d8841f51 | 325 | int i2c_slave_receive(i2c_t *obj) { |
bogdanm | 13:0645d8841f51 | 326 | int status; |
bogdanm | 13:0645d8841f51 | 327 | int retval; |
bogdanm | 13:0645d8841f51 | 328 | |
bogdanm | 13:0645d8841f51 | 329 | status = i2c_status(obj); |
bogdanm | 13:0645d8841f51 | 330 | switch(status) { |
bogdanm | 13:0645d8841f51 | 331 | case 0x60: retval = 3; break; |
bogdanm | 13:0645d8841f51 | 332 | case 0x70: retval = 2; break; |
bogdanm | 13:0645d8841f51 | 333 | case 0xA8: retval = 1; break; |
bogdanm | 13:0645d8841f51 | 334 | default : retval = 0; break; |
bogdanm | 13:0645d8841f51 | 335 | } |
bogdanm | 13:0645d8841f51 | 336 | |
bogdanm | 13:0645d8841f51 | 337 | return(retval); |
bogdanm | 13:0645d8841f51 | 338 | } |
bogdanm | 13:0645d8841f51 | 339 | |
bogdanm | 13:0645d8841f51 | 340 | int i2c_slave_read(i2c_t *obj, char *data, int length) { |
bogdanm | 13:0645d8841f51 | 341 | int count = 0; |
bogdanm | 13:0645d8841f51 | 342 | int status; |
bogdanm | 13:0645d8841f51 | 343 | |
bogdanm | 13:0645d8841f51 | 344 | do { |
bogdanm | 13:0645d8841f51 | 345 | i2c_clear_SI(obj); |
bogdanm | 13:0645d8841f51 | 346 | i2c_wait_SI(obj); |
bogdanm | 13:0645d8841f51 | 347 | status = i2c_status(obj); |
bogdanm | 13:0645d8841f51 | 348 | if((status == 0x80) || (status == 0x90)) { |
bogdanm | 13:0645d8841f51 | 349 | data[count] = I2C_DAT(obj) & 0xFF; |
bogdanm | 13:0645d8841f51 | 350 | } |
bogdanm | 13:0645d8841f51 | 351 | count++; |
bogdanm | 13:0645d8841f51 | 352 | } while (((status == 0x80) || (status == 0x90) || |
bogdanm | 13:0645d8841f51 | 353 | (status == 0x060) || (status == 0x70)) && (count < length)); |
bogdanm | 13:0645d8841f51 | 354 | |
bogdanm | 13:0645d8841f51 | 355 | if(status != 0xA0) { |
bogdanm | 13:0645d8841f51 | 356 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 357 | } |
bogdanm | 13:0645d8841f51 | 358 | |
bogdanm | 13:0645d8841f51 | 359 | i2c_clear_SI(obj); |
bogdanm | 13:0645d8841f51 | 360 | |
bogdanm | 13:0645d8841f51 | 361 | return count; |
bogdanm | 13:0645d8841f51 | 362 | } |
bogdanm | 13:0645d8841f51 | 363 | |
bogdanm | 13:0645d8841f51 | 364 | int i2c_slave_write(i2c_t *obj, const char *data, int length) { |
bogdanm | 13:0645d8841f51 | 365 | int count = 0; |
bogdanm | 13:0645d8841f51 | 366 | int status; |
bogdanm | 13:0645d8841f51 | 367 | |
bogdanm | 13:0645d8841f51 | 368 | if(length <= 0) { |
bogdanm | 13:0645d8841f51 | 369 | return(0); |
bogdanm | 13:0645d8841f51 | 370 | } |
bogdanm | 13:0645d8841f51 | 371 | |
bogdanm | 13:0645d8841f51 | 372 | do { |
bogdanm | 13:0645d8841f51 | 373 | status = i2c_do_write(obj, data[count], 0); |
bogdanm | 13:0645d8841f51 | 374 | count++; |
bogdanm | 13:0645d8841f51 | 375 | } while ((count < length) && (status == 0xB8)); |
bogdanm | 13:0645d8841f51 | 376 | |
bogdanm | 13:0645d8841f51 | 377 | if((status != 0xC0) && (status != 0xC8)) { |
bogdanm | 13:0645d8841f51 | 378 | i2c_stop(obj); |
bogdanm | 13:0645d8841f51 | 379 | } |
bogdanm | 13:0645d8841f51 | 380 | |
bogdanm | 13:0645d8841f51 | 381 | i2c_clear_SI(obj); |
bogdanm | 13:0645d8841f51 | 382 | |
bogdanm | 13:0645d8841f51 | 383 | return(count); |
bogdanm | 13:0645d8841f51 | 384 | } |
bogdanm | 13:0645d8841f51 | 385 | |
bogdanm | 13:0645d8841f51 | 386 | void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask) { |
bogdanm | 13:0645d8841f51 | 387 | uint32_t addr; |
bogdanm | 13:0645d8841f51 | 388 | |
bogdanm | 13:0645d8841f51 | 389 | if ((idx >= 0) && (idx <= 3)) { |
bogdanm | 13:0645d8841f51 | 390 | addr = ((uint32_t)obj->i2c) + I2C_addr_offset[0][idx]; |
bogdanm | 13:0645d8841f51 | 391 | *((uint32_t *) addr) = address & 0xFF; |
bogdanm | 13:0645d8841f51 | 392 | } |
bogdanm | 13:0645d8841f51 | 393 | } |