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Dependents: Seeed_Barometer_Sensor_Example
Fork of mbed-src by
targets/hal/TARGET_NXP/TARGET_LPC408X/i2c_api.c@34:a3c7023e45de, 2013-10-11 (annotated)
- Committer:
- mbed_official
- Date:
- Fri Oct 11 13:30:08 2013 +0100
- Revision:
- 34:a3c7023e45de
- Parent:
- 15:4892fe388435
- Child:
- 227:7bd0639b8911
Synchronized with git revision eaafc74ae29c565a716b8c5f9d5899ef7d680b8b
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| bogdanm | 15:4892fe388435 | 1 | /* mbed Microcontroller Library |
| bogdanm | 15:4892fe388435 | 2 | * Copyright (c) 2006-2013 ARM Limited |
| bogdanm | 15:4892fe388435 | 3 | * |
| bogdanm | 15:4892fe388435 | 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| bogdanm | 15:4892fe388435 | 5 | * you may not use this file except in compliance with the License. |
| bogdanm | 15:4892fe388435 | 6 | * You may obtain a copy of the License at |
| bogdanm | 15:4892fe388435 | 7 | * |
| bogdanm | 15:4892fe388435 | 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| bogdanm | 15:4892fe388435 | 9 | * |
| bogdanm | 15:4892fe388435 | 10 | * Unless required by applicable law or agreed to in writing, software |
| bogdanm | 15:4892fe388435 | 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| bogdanm | 15:4892fe388435 | 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| bogdanm | 15:4892fe388435 | 13 | * See the License for the specific language governing permissions and |
| bogdanm | 15:4892fe388435 | 14 | * limitations under the License. |
| bogdanm | 15:4892fe388435 | 15 | */ |
| bogdanm | 15:4892fe388435 | 16 | #include "i2c_api.h" |
| bogdanm | 15:4892fe388435 | 17 | #include "cmsis.h" |
| bogdanm | 15:4892fe388435 | 18 | #include "pinmap.h" |
| bogdanm | 15:4892fe388435 | 19 | #include "error.h" |
| bogdanm | 15:4892fe388435 | 20 | |
| bogdanm | 15:4892fe388435 | 21 | static const PinMap PinMap_I2C_SDA[] = { |
| bogdanm | 15:4892fe388435 | 22 | {P0_0 , I2C_1, 3}, |
| bogdanm | 15:4892fe388435 | 23 | {P0_10, I2C_2, 2}, |
| bogdanm | 15:4892fe388435 | 24 | {P0_19, I2C_1, 3}, |
| bogdanm | 15:4892fe388435 | 25 | {P0_27, I2C_0, 1}, |
| bogdanm | 15:4892fe388435 | 26 | {P1_15, I2C_2, 3}, |
| bogdanm | 15:4892fe388435 | 27 | {P1_30, I2C_0, 4}, |
| bogdanm | 15:4892fe388435 | 28 | {P2_14, I2C_1, 2}, |
| bogdanm | 15:4892fe388435 | 29 | {P2_30, I2C_2, 2}, |
| bogdanm | 15:4892fe388435 | 30 | {P4_20, I2C_2, 4}, |
| bogdanm | 15:4892fe388435 | 31 | {P5_2, I2C_0, 5}, |
| bogdanm | 15:4892fe388435 | 32 | {NC , NC , 0} |
| bogdanm | 15:4892fe388435 | 33 | }; |
| bogdanm | 15:4892fe388435 | 34 | |
| bogdanm | 15:4892fe388435 | 35 | static const PinMap PinMap_I2C_SCL[] = { |
| bogdanm | 15:4892fe388435 | 36 | {P0_1 , I2C_1, 3}, |
| bogdanm | 15:4892fe388435 | 37 | {P0_11, I2C_2, 2}, |
| bogdanm | 15:4892fe388435 | 38 | {P0_20, I2C_1, 3}, |
| bogdanm | 15:4892fe388435 | 39 | {P0_28, I2C_0, 1}, |
| bogdanm | 15:4892fe388435 | 40 | {P1_31, I2C_0, 4}, |
| bogdanm | 15:4892fe388435 | 41 | {P2_15, I2C_1, 2}, |
| bogdanm | 15:4892fe388435 | 42 | {P2_31, I2C_2, 2}, |
| bogdanm | 15:4892fe388435 | 43 | {P4_21, I2C_2, 2}, |
| bogdanm | 15:4892fe388435 | 44 | {P4_29, I2C_2, 4}, |
| bogdanm | 15:4892fe388435 | 45 | {P5_3, I2C_0, 5}, |
| bogdanm | 15:4892fe388435 | 46 | {NC , NC, 0} |
| bogdanm | 15:4892fe388435 | 47 | }; |
| bogdanm | 15:4892fe388435 | 48 | |
| bogdanm | 15:4892fe388435 | 49 | #define I2C_CONSET(x) (x->i2c->CONSET) |
| bogdanm | 15:4892fe388435 | 50 | #define I2C_CONCLR(x) (x->i2c->CONCLR) |
| bogdanm | 15:4892fe388435 | 51 | #define I2C_STAT(x) (x->i2c->STAT) |
| bogdanm | 15:4892fe388435 | 52 | #define I2C_DAT(x) (x->i2c->DAT) |
| bogdanm | 15:4892fe388435 | 53 | #define I2C_SCLL(x, val) (x->i2c->SCLL = val) |
| bogdanm | 15:4892fe388435 | 54 | #define I2C_SCLH(x, val) (x->i2c->SCLH = val) |
| bogdanm | 15:4892fe388435 | 55 | |
| bogdanm | 15:4892fe388435 | 56 | static const uint32_t I2C_addr_offset[2][4] = { |
| bogdanm | 15:4892fe388435 | 57 | {0x0C, 0x20, 0x24, 0x28}, |
| bogdanm | 15:4892fe388435 | 58 | {0x30, 0x34, 0x38, 0x3C} |
| bogdanm | 15:4892fe388435 | 59 | }; |
| bogdanm | 15:4892fe388435 | 60 | |
| bogdanm | 15:4892fe388435 | 61 | static inline void i2c_conclr(i2c_t *obj, int start, int stop, int interrupt, int acknowledge) { |
| bogdanm | 15:4892fe388435 | 62 | I2C_CONCLR(obj) = (start << 5) |
| bogdanm | 15:4892fe388435 | 63 | | (stop << 4) |
| bogdanm | 15:4892fe388435 | 64 | | (interrupt << 3) |
| bogdanm | 15:4892fe388435 | 65 | | (acknowledge << 2); |
| bogdanm | 15:4892fe388435 | 66 | } |
| bogdanm | 15:4892fe388435 | 67 | |
| bogdanm | 15:4892fe388435 | 68 | static inline void i2c_conset(i2c_t *obj, int start, int stop, int interrupt, int acknowledge) { |
| bogdanm | 15:4892fe388435 | 69 | I2C_CONSET(obj) = (start << 5) |
| bogdanm | 15:4892fe388435 | 70 | | (stop << 4) |
| bogdanm | 15:4892fe388435 | 71 | | (interrupt << 3) |
| bogdanm | 15:4892fe388435 | 72 | | (acknowledge << 2); |
| bogdanm | 15:4892fe388435 | 73 | } |
| bogdanm | 15:4892fe388435 | 74 | |
| bogdanm | 15:4892fe388435 | 75 | // Clear the Serial Interrupt (SI) |
| bogdanm | 15:4892fe388435 | 76 | static inline void i2c_clear_SI(i2c_t *obj) { |
| bogdanm | 15:4892fe388435 | 77 | i2c_conclr(obj, 0, 0, 1, 0); |
| bogdanm | 15:4892fe388435 | 78 | } |
| bogdanm | 15:4892fe388435 | 79 | |
| bogdanm | 15:4892fe388435 | 80 | static inline int i2c_status(i2c_t *obj) { |
| bogdanm | 15:4892fe388435 | 81 | return I2C_STAT(obj); |
| bogdanm | 15:4892fe388435 | 82 | } |
| bogdanm | 15:4892fe388435 | 83 | |
| bogdanm | 15:4892fe388435 | 84 | // Wait until the Serial Interrupt (SI) is set |
| bogdanm | 15:4892fe388435 | 85 | static int i2c_wait_SI(i2c_t *obj) { |
| bogdanm | 15:4892fe388435 | 86 | int timeout = 0; |
| bogdanm | 15:4892fe388435 | 87 | while (!(I2C_CONSET(obj) & (1 << 3))) { |
| bogdanm | 15:4892fe388435 | 88 | timeout++; |
| bogdanm | 15:4892fe388435 | 89 | if (timeout > 100000) return -1; |
| bogdanm | 15:4892fe388435 | 90 | } |
| bogdanm | 15:4892fe388435 | 91 | return 0; |
| bogdanm | 15:4892fe388435 | 92 | } |
| bogdanm | 15:4892fe388435 | 93 | |
| bogdanm | 15:4892fe388435 | 94 | static inline void i2c_interface_enable(i2c_t *obj) { |
| bogdanm | 15:4892fe388435 | 95 | I2C_CONSET(obj) = 0x40; |
| bogdanm | 15:4892fe388435 | 96 | } |
| bogdanm | 15:4892fe388435 | 97 | |
| bogdanm | 15:4892fe388435 | 98 | static inline void i2c_power_enable(i2c_t *obj) { |
| bogdanm | 15:4892fe388435 | 99 | switch ((int)obj->i2c) { |
| bogdanm | 15:4892fe388435 | 100 | case I2C_0: LPC_SC->PCONP |= 1 << 7; break; |
| bogdanm | 15:4892fe388435 | 101 | case I2C_1: LPC_SC->PCONP |= 1 << 19; break; |
| bogdanm | 15:4892fe388435 | 102 | case I2C_2: LPC_SC->PCONP |= 1 << 26; break; |
| bogdanm | 15:4892fe388435 | 103 | } |
| bogdanm | 15:4892fe388435 | 104 | } |
| bogdanm | 15:4892fe388435 | 105 | |
| bogdanm | 15:4892fe388435 | 106 | void i2c_init(i2c_t *obj, PinName sda, PinName scl) { |
| bogdanm | 15:4892fe388435 | 107 | // determine the SPI to use |
| bogdanm | 15:4892fe388435 | 108 | I2CName i2c_sda = (I2CName)pinmap_peripheral(sda, PinMap_I2C_SDA); |
| bogdanm | 15:4892fe388435 | 109 | I2CName i2c_scl = (I2CName)pinmap_peripheral(scl, PinMap_I2C_SCL); |
| bogdanm | 15:4892fe388435 | 110 | obj->i2c = (LPC_I2C_TypeDef *)pinmap_merge(i2c_sda, i2c_scl); |
| bogdanm | 15:4892fe388435 | 111 | if ((int)obj->i2c == NC) { |
| bogdanm | 15:4892fe388435 | 112 | error("I2C pin mapping failed"); |
| bogdanm | 15:4892fe388435 | 113 | } |
| bogdanm | 15:4892fe388435 | 114 | |
| bogdanm | 15:4892fe388435 | 115 | // enable power |
| bogdanm | 15:4892fe388435 | 116 | i2c_power_enable(obj); |
| bogdanm | 15:4892fe388435 | 117 | |
| bogdanm | 15:4892fe388435 | 118 | // set default frequency at 100k |
| bogdanm | 15:4892fe388435 | 119 | i2c_frequency(obj, 100000); |
| bogdanm | 15:4892fe388435 | 120 | i2c_conclr(obj, 1, 1, 1, 1); |
| bogdanm | 15:4892fe388435 | 121 | i2c_interface_enable(obj); |
| bogdanm | 15:4892fe388435 | 122 | |
| bogdanm | 15:4892fe388435 | 123 | pinmap_pinout(sda, PinMap_I2C_SDA); |
| bogdanm | 15:4892fe388435 | 124 | pinmap_pinout(scl, PinMap_I2C_SCL); |
| mbed_official | 34:a3c7023e45de | 125 | |
| mbed_official | 34:a3c7023e45de | 126 | // OpenDrain must explicitly be enabled for p0.0 and p0.1 |
| mbed_official | 34:a3c7023e45de | 127 | if (sda == P0_0) { |
| mbed_official | 34:a3c7023e45de | 128 | pin_mode(sda, OpenDrain); |
| mbed_official | 34:a3c7023e45de | 129 | } |
| mbed_official | 34:a3c7023e45de | 130 | if (scl == P0_1) { |
| mbed_official | 34:a3c7023e45de | 131 | pin_mode(scl, OpenDrain); |
| mbed_official | 34:a3c7023e45de | 132 | } |
| mbed_official | 34:a3c7023e45de | 133 | |
| bogdanm | 15:4892fe388435 | 134 | } |
| bogdanm | 15:4892fe388435 | 135 | |
| bogdanm | 15:4892fe388435 | 136 | inline int i2c_start(i2c_t *obj) { |
| bogdanm | 15:4892fe388435 | 137 | int status = 0; |
| bogdanm | 15:4892fe388435 | 138 | // 8.1 Before master mode can be entered, I2CON must be initialised to: |
| bogdanm | 15:4892fe388435 | 139 | // - I2EN STA STO SI AA - - |
| bogdanm | 15:4892fe388435 | 140 | // - 1 0 0 0 x - - |
| bogdanm | 15:4892fe388435 | 141 | // if AA = 0, it can't enter slave mode |
| bogdanm | 15:4892fe388435 | 142 | i2c_conclr(obj, 1, 1, 1, 1); |
| bogdanm | 15:4892fe388435 | 143 | |
| bogdanm | 15:4892fe388435 | 144 | // The master mode may now be entered by setting the STA bit |
| bogdanm | 15:4892fe388435 | 145 | // this will generate a start condition when the bus becomes free |
| bogdanm | 15:4892fe388435 | 146 | i2c_conset(obj, 1, 0, 0, 1); |
| bogdanm | 15:4892fe388435 | 147 | |
| bogdanm | 15:4892fe388435 | 148 | i2c_wait_SI(obj); |
| bogdanm | 15:4892fe388435 | 149 | status = i2c_status(obj); |
| bogdanm | 15:4892fe388435 | 150 | |
| bogdanm | 15:4892fe388435 | 151 | // Clear start bit now transmitted, and interrupt bit |
| bogdanm | 15:4892fe388435 | 152 | i2c_conclr(obj, 1, 0, 0, 0); |
| bogdanm | 15:4892fe388435 | 153 | return status; |
| bogdanm | 15:4892fe388435 | 154 | } |
| bogdanm | 15:4892fe388435 | 155 | |
| bogdanm | 15:4892fe388435 | 156 | inline int i2c_stop(i2c_t *obj) { |
| bogdanm | 15:4892fe388435 | 157 | int timeout = 0; |
| bogdanm | 15:4892fe388435 | 158 | |
| bogdanm | 15:4892fe388435 | 159 | // write the stop bit |
| bogdanm | 15:4892fe388435 | 160 | i2c_conset(obj, 0, 1, 0, 0); |
| bogdanm | 15:4892fe388435 | 161 | i2c_clear_SI(obj); |
| bogdanm | 15:4892fe388435 | 162 | |
| bogdanm | 15:4892fe388435 | 163 | // wait for STO bit to reset |
| bogdanm | 15:4892fe388435 | 164 | while(I2C_CONSET(obj) & (1 << 4)) { |
| bogdanm | 15:4892fe388435 | 165 | timeout ++; |
| bogdanm | 15:4892fe388435 | 166 | if (timeout > 100000) return 1; |
| bogdanm | 15:4892fe388435 | 167 | } |
| bogdanm | 15:4892fe388435 | 168 | |
| bogdanm | 15:4892fe388435 | 169 | return 0; |
| bogdanm | 15:4892fe388435 | 170 | } |
| bogdanm | 15:4892fe388435 | 171 | |
| bogdanm | 15:4892fe388435 | 172 | |
| bogdanm | 15:4892fe388435 | 173 | static inline int i2c_do_write(i2c_t *obj, int value, uint8_t addr) { |
| bogdanm | 15:4892fe388435 | 174 | // write the data |
| bogdanm | 15:4892fe388435 | 175 | I2C_DAT(obj) = value; |
| bogdanm | 15:4892fe388435 | 176 | |
| bogdanm | 15:4892fe388435 | 177 | // clear SI to init a send |
| bogdanm | 15:4892fe388435 | 178 | i2c_clear_SI(obj); |
| bogdanm | 15:4892fe388435 | 179 | |
| bogdanm | 15:4892fe388435 | 180 | // wait and return status |
| bogdanm | 15:4892fe388435 | 181 | i2c_wait_SI(obj); |
| bogdanm | 15:4892fe388435 | 182 | return i2c_status(obj); |
| bogdanm | 15:4892fe388435 | 183 | } |
| bogdanm | 15:4892fe388435 | 184 | |
| bogdanm | 15:4892fe388435 | 185 | static inline int i2c_do_read(i2c_t *obj, int last) { |
| bogdanm | 15:4892fe388435 | 186 | // we are in state 0x40 (SLA+R tx'd) or 0x50 (data rx'd and ack) |
| bogdanm | 15:4892fe388435 | 187 | if(last) { |
| bogdanm | 15:4892fe388435 | 188 | i2c_conclr(obj, 0, 0, 0, 1); // send a NOT ACK |
| bogdanm | 15:4892fe388435 | 189 | } else { |
| bogdanm | 15:4892fe388435 | 190 | i2c_conset(obj, 0, 0, 0, 1); // send a ACK |
| bogdanm | 15:4892fe388435 | 191 | } |
| bogdanm | 15:4892fe388435 | 192 | |
| bogdanm | 15:4892fe388435 | 193 | // accept byte |
| bogdanm | 15:4892fe388435 | 194 | i2c_clear_SI(obj); |
| bogdanm | 15:4892fe388435 | 195 | |
| bogdanm | 15:4892fe388435 | 196 | // wait for it to arrive |
| bogdanm | 15:4892fe388435 | 197 | i2c_wait_SI(obj); |
| bogdanm | 15:4892fe388435 | 198 | |
| bogdanm | 15:4892fe388435 | 199 | // return the data |
| bogdanm | 15:4892fe388435 | 200 | return (I2C_DAT(obj) & 0xFF); |
| bogdanm | 15:4892fe388435 | 201 | } |
| bogdanm | 15:4892fe388435 | 202 | |
| bogdanm | 15:4892fe388435 | 203 | void i2c_frequency(i2c_t *obj, int hz) { |
| bogdanm | 15:4892fe388435 | 204 | uint32_t PCLK = PeripheralClock; |
| bogdanm | 15:4892fe388435 | 205 | uint32_t pulse = PCLK / (hz * 2); |
| bogdanm | 15:4892fe388435 | 206 | |
| bogdanm | 15:4892fe388435 | 207 | // I2C Rate |
| bogdanm | 15:4892fe388435 | 208 | I2C_SCLL(obj, pulse); |
| bogdanm | 15:4892fe388435 | 209 | I2C_SCLH(obj, pulse); |
| bogdanm | 15:4892fe388435 | 210 | } |
| bogdanm | 15:4892fe388435 | 211 | |
| bogdanm | 15:4892fe388435 | 212 | // The I2C does a read or a write as a whole operation |
| bogdanm | 15:4892fe388435 | 213 | // There are two types of error conditions it can encounter |
| bogdanm | 15:4892fe388435 | 214 | // 1) it can not obtain the bus |
| bogdanm | 15:4892fe388435 | 215 | // 2) it gets error responses at part of the transmission |
| bogdanm | 15:4892fe388435 | 216 | // |
| bogdanm | 15:4892fe388435 | 217 | // We tackle them as follows: |
| bogdanm | 15:4892fe388435 | 218 | // 1) we retry until we get the bus. we could have a "timeout" if we can not get it |
| bogdanm | 15:4892fe388435 | 219 | // which basically turns it in to a 2) |
| bogdanm | 15:4892fe388435 | 220 | // 2) on error, we use the standard error mechanisms to report/debug |
| bogdanm | 15:4892fe388435 | 221 | // |
| bogdanm | 15:4892fe388435 | 222 | // Therefore an I2C transaction should always complete. If it doesn't it is usually |
| bogdanm | 15:4892fe388435 | 223 | // because something is setup wrong (e.g. wiring), and we don't need to programatically |
| bogdanm | 15:4892fe388435 | 224 | // check for that |
| bogdanm | 15:4892fe388435 | 225 | int i2c_read(i2c_t *obj, int address, char *data, int length, int stop) { |
| bogdanm | 15:4892fe388435 | 226 | int count, status; |
| bogdanm | 15:4892fe388435 | 227 | |
| bogdanm | 15:4892fe388435 | 228 | status = i2c_start(obj); |
| bogdanm | 15:4892fe388435 | 229 | |
| bogdanm | 15:4892fe388435 | 230 | if ((status != 0x10) && (status != 0x08)) { |
| bogdanm | 15:4892fe388435 | 231 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 232 | return I2C_ERROR_BUS_BUSY; |
| bogdanm | 15:4892fe388435 | 233 | } |
| bogdanm | 15:4892fe388435 | 234 | |
| bogdanm | 15:4892fe388435 | 235 | status = i2c_do_write(obj, (address | 0x01), 1); |
| bogdanm | 15:4892fe388435 | 236 | if (status != 0x40) { |
| bogdanm | 15:4892fe388435 | 237 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 238 | return I2C_ERROR_NO_SLAVE; |
| bogdanm | 15:4892fe388435 | 239 | } |
| bogdanm | 15:4892fe388435 | 240 | |
| bogdanm | 15:4892fe388435 | 241 | // Read in all except last byte |
| bogdanm | 15:4892fe388435 | 242 | for (count = 0; count < (length - 1); count++) { |
| bogdanm | 15:4892fe388435 | 243 | int value = i2c_do_read(obj, 0); |
| bogdanm | 15:4892fe388435 | 244 | status = i2c_status(obj); |
| bogdanm | 15:4892fe388435 | 245 | if (status != 0x50) { |
| bogdanm | 15:4892fe388435 | 246 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 247 | return count; |
| bogdanm | 15:4892fe388435 | 248 | } |
| bogdanm | 15:4892fe388435 | 249 | data[count] = (char) value; |
| bogdanm | 15:4892fe388435 | 250 | } |
| bogdanm | 15:4892fe388435 | 251 | |
| bogdanm | 15:4892fe388435 | 252 | // read in last byte |
| bogdanm | 15:4892fe388435 | 253 | int value = i2c_do_read(obj, 1); |
| bogdanm | 15:4892fe388435 | 254 | status = i2c_status(obj); |
| bogdanm | 15:4892fe388435 | 255 | if (status != 0x58) { |
| bogdanm | 15:4892fe388435 | 256 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 257 | return length - 1; |
| bogdanm | 15:4892fe388435 | 258 | } |
| bogdanm | 15:4892fe388435 | 259 | |
| bogdanm | 15:4892fe388435 | 260 | data[count] = (char) value; |
| bogdanm | 15:4892fe388435 | 261 | |
| bogdanm | 15:4892fe388435 | 262 | // If not repeated start, send stop. |
| bogdanm | 15:4892fe388435 | 263 | if (stop) { |
| bogdanm | 15:4892fe388435 | 264 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 265 | } |
| bogdanm | 15:4892fe388435 | 266 | |
| bogdanm | 15:4892fe388435 | 267 | return length; |
| bogdanm | 15:4892fe388435 | 268 | } |
| bogdanm | 15:4892fe388435 | 269 | |
| bogdanm | 15:4892fe388435 | 270 | int i2c_write(i2c_t *obj, int address, const char *data, int length, int stop) { |
| bogdanm | 15:4892fe388435 | 271 | int i, status; |
| bogdanm | 15:4892fe388435 | 272 | |
| bogdanm | 15:4892fe388435 | 273 | status = i2c_start(obj); |
| bogdanm | 15:4892fe388435 | 274 | |
| bogdanm | 15:4892fe388435 | 275 | if ((status != 0x10) && (status != 0x08)) { |
| bogdanm | 15:4892fe388435 | 276 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 277 | return I2C_ERROR_BUS_BUSY; |
| bogdanm | 15:4892fe388435 | 278 | } |
| bogdanm | 15:4892fe388435 | 279 | |
| bogdanm | 15:4892fe388435 | 280 | status = i2c_do_write(obj, (address & 0xFE), 1); |
| bogdanm | 15:4892fe388435 | 281 | if (status != 0x18) { |
| bogdanm | 15:4892fe388435 | 282 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 283 | return I2C_ERROR_NO_SLAVE; |
| bogdanm | 15:4892fe388435 | 284 | } |
| bogdanm | 15:4892fe388435 | 285 | |
| bogdanm | 15:4892fe388435 | 286 | for (i=0; i<length; i++) { |
| bogdanm | 15:4892fe388435 | 287 | status = i2c_do_write(obj, data[i], 0); |
| bogdanm | 15:4892fe388435 | 288 | if (status != 0x28) { |
| bogdanm | 15:4892fe388435 | 289 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 290 | return i; |
| bogdanm | 15:4892fe388435 | 291 | } |
| bogdanm | 15:4892fe388435 | 292 | } |
| bogdanm | 15:4892fe388435 | 293 | |
| bogdanm | 15:4892fe388435 | 294 | // clearing the serial interrupt here might cause an unintended rewrite of the last byte |
| bogdanm | 15:4892fe388435 | 295 | // see also issue report https://mbed.org/users/mbed_official/code/mbed/issues/1 |
| bogdanm | 15:4892fe388435 | 296 | // i2c_clear_SI(obj); |
| bogdanm | 15:4892fe388435 | 297 | |
| bogdanm | 15:4892fe388435 | 298 | // If not repeated start, send stop. |
| bogdanm | 15:4892fe388435 | 299 | if (stop) { |
| bogdanm | 15:4892fe388435 | 300 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 301 | } |
| bogdanm | 15:4892fe388435 | 302 | |
| bogdanm | 15:4892fe388435 | 303 | return length; |
| bogdanm | 15:4892fe388435 | 304 | } |
| bogdanm | 15:4892fe388435 | 305 | |
| bogdanm | 15:4892fe388435 | 306 | void i2c_reset(i2c_t *obj) { |
| bogdanm | 15:4892fe388435 | 307 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 308 | } |
| bogdanm | 15:4892fe388435 | 309 | |
| bogdanm | 15:4892fe388435 | 310 | int i2c_byte_read(i2c_t *obj, int last) { |
| bogdanm | 15:4892fe388435 | 311 | return (i2c_do_read(obj, last) & 0xFF); |
| bogdanm | 15:4892fe388435 | 312 | } |
| bogdanm | 15:4892fe388435 | 313 | |
| bogdanm | 15:4892fe388435 | 314 | int i2c_byte_write(i2c_t *obj, int data) { |
| bogdanm | 15:4892fe388435 | 315 | int ack; |
| bogdanm | 15:4892fe388435 | 316 | int status = i2c_do_write(obj, (data & 0xFF), 0); |
| bogdanm | 15:4892fe388435 | 317 | |
| bogdanm | 15:4892fe388435 | 318 | switch(status) { |
| bogdanm | 15:4892fe388435 | 319 | case 0x18: case 0x28: // Master transmit ACKs |
| bogdanm | 15:4892fe388435 | 320 | ack = 1; |
| bogdanm | 15:4892fe388435 | 321 | break; |
| bogdanm | 15:4892fe388435 | 322 | |
| bogdanm | 15:4892fe388435 | 323 | case 0x40: // Master receive address transmitted ACK |
| bogdanm | 15:4892fe388435 | 324 | ack = 1; |
| bogdanm | 15:4892fe388435 | 325 | break; |
| bogdanm | 15:4892fe388435 | 326 | |
| bogdanm | 15:4892fe388435 | 327 | case 0xB8: // Slave transmit ACK |
| bogdanm | 15:4892fe388435 | 328 | ack = 1; |
| bogdanm | 15:4892fe388435 | 329 | break; |
| bogdanm | 15:4892fe388435 | 330 | |
| bogdanm | 15:4892fe388435 | 331 | default: |
| bogdanm | 15:4892fe388435 | 332 | ack = 0; |
| bogdanm | 15:4892fe388435 | 333 | break; |
| bogdanm | 15:4892fe388435 | 334 | } |
| bogdanm | 15:4892fe388435 | 335 | |
| bogdanm | 15:4892fe388435 | 336 | return ack; |
| bogdanm | 15:4892fe388435 | 337 | } |
| bogdanm | 15:4892fe388435 | 338 | |
| bogdanm | 15:4892fe388435 | 339 | void i2c_slave_mode(i2c_t *obj, int enable_slave) { |
| bogdanm | 15:4892fe388435 | 340 | if (enable_slave != 0) { |
| bogdanm | 15:4892fe388435 | 341 | i2c_conclr(obj, 1, 1, 1, 0); |
| bogdanm | 15:4892fe388435 | 342 | i2c_conset(obj, 0, 0, 0, 1); |
| bogdanm | 15:4892fe388435 | 343 | } else { |
| bogdanm | 15:4892fe388435 | 344 | i2c_conclr(obj, 1, 1, 1, 1); |
| bogdanm | 15:4892fe388435 | 345 | } |
| bogdanm | 15:4892fe388435 | 346 | } |
| bogdanm | 15:4892fe388435 | 347 | |
| bogdanm | 15:4892fe388435 | 348 | int i2c_slave_receive(i2c_t *obj) { |
| bogdanm | 15:4892fe388435 | 349 | int status; |
| bogdanm | 15:4892fe388435 | 350 | int retval; |
| bogdanm | 15:4892fe388435 | 351 | |
| bogdanm | 15:4892fe388435 | 352 | status = i2c_status(obj); |
| bogdanm | 15:4892fe388435 | 353 | switch(status) { |
| bogdanm | 15:4892fe388435 | 354 | case 0x60: retval = 3; break; |
| bogdanm | 15:4892fe388435 | 355 | case 0x70: retval = 2; break; |
| bogdanm | 15:4892fe388435 | 356 | case 0xA8: retval = 1; break; |
| bogdanm | 15:4892fe388435 | 357 | default : retval = 0; break; |
| bogdanm | 15:4892fe388435 | 358 | } |
| bogdanm | 15:4892fe388435 | 359 | |
| bogdanm | 15:4892fe388435 | 360 | return(retval); |
| bogdanm | 15:4892fe388435 | 361 | } |
| bogdanm | 15:4892fe388435 | 362 | |
| bogdanm | 15:4892fe388435 | 363 | int i2c_slave_read(i2c_t *obj, char *data, int length) { |
| bogdanm | 15:4892fe388435 | 364 | int count = 0; |
| bogdanm | 15:4892fe388435 | 365 | int status; |
| bogdanm | 15:4892fe388435 | 366 | |
| bogdanm | 15:4892fe388435 | 367 | do { |
| bogdanm | 15:4892fe388435 | 368 | i2c_clear_SI(obj); |
| bogdanm | 15:4892fe388435 | 369 | i2c_wait_SI(obj); |
| bogdanm | 15:4892fe388435 | 370 | status = i2c_status(obj); |
| bogdanm | 15:4892fe388435 | 371 | if((status == 0x80) || (status == 0x90)) { |
| bogdanm | 15:4892fe388435 | 372 | data[count] = I2C_DAT(obj) & 0xFF; |
| bogdanm | 15:4892fe388435 | 373 | } |
| bogdanm | 15:4892fe388435 | 374 | count++; |
| bogdanm | 15:4892fe388435 | 375 | } while (((status == 0x80) || (status == 0x90) || |
| bogdanm | 15:4892fe388435 | 376 | (status == 0x060) || (status == 0x70)) && (count < length)); |
| bogdanm | 15:4892fe388435 | 377 | |
| bogdanm | 15:4892fe388435 | 378 | if(status != 0xA0) { |
| bogdanm | 15:4892fe388435 | 379 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 380 | } |
| bogdanm | 15:4892fe388435 | 381 | |
| bogdanm | 15:4892fe388435 | 382 | i2c_clear_SI(obj); |
| bogdanm | 15:4892fe388435 | 383 | |
| bogdanm | 15:4892fe388435 | 384 | return count; |
| bogdanm | 15:4892fe388435 | 385 | } |
| bogdanm | 15:4892fe388435 | 386 | |
| bogdanm | 15:4892fe388435 | 387 | int i2c_slave_write(i2c_t *obj, const char *data, int length) { |
| bogdanm | 15:4892fe388435 | 388 | int count = 0; |
| bogdanm | 15:4892fe388435 | 389 | int status; |
| bogdanm | 15:4892fe388435 | 390 | |
| bogdanm | 15:4892fe388435 | 391 | if(length <= 0) { |
| bogdanm | 15:4892fe388435 | 392 | return(0); |
| bogdanm | 15:4892fe388435 | 393 | } |
| bogdanm | 15:4892fe388435 | 394 | |
| bogdanm | 15:4892fe388435 | 395 | do { |
| bogdanm | 15:4892fe388435 | 396 | status = i2c_do_write(obj, data[count], 0); |
| bogdanm | 15:4892fe388435 | 397 | count++; |
| bogdanm | 15:4892fe388435 | 398 | } while ((count < length) && (status == 0xB8)); |
| bogdanm | 15:4892fe388435 | 399 | |
| bogdanm | 15:4892fe388435 | 400 | if((status != 0xC0) && (status != 0xC8)) { |
| bogdanm | 15:4892fe388435 | 401 | i2c_stop(obj); |
| bogdanm | 15:4892fe388435 | 402 | } |
| bogdanm | 15:4892fe388435 | 403 | |
| bogdanm | 15:4892fe388435 | 404 | i2c_clear_SI(obj); |
| bogdanm | 15:4892fe388435 | 405 | |
| bogdanm | 15:4892fe388435 | 406 | return(count); |
| bogdanm | 15:4892fe388435 | 407 | } |
| bogdanm | 15:4892fe388435 | 408 | |
| bogdanm | 15:4892fe388435 | 409 | void i2c_slave_address(i2c_t *obj, int idx, uint32_t address, uint32_t mask) { |
| bogdanm | 15:4892fe388435 | 410 | uint32_t addr; |
| bogdanm | 15:4892fe388435 | 411 | |
| bogdanm | 15:4892fe388435 | 412 | if ((idx >= 0) && (idx <= 3)) { |
| bogdanm | 15:4892fe388435 | 413 | addr = ((uint32_t)obj->i2c) + I2C_addr_offset[0][idx]; |
| bogdanm | 15:4892fe388435 | 414 | *((uint32_t *) addr) = address & 0xFF; |
| bogdanm | 15:4892fe388435 | 415 | addr = ((uint32_t)obj->i2c) + I2C_addr_offset[1][idx]; |
| bogdanm | 15:4892fe388435 | 416 | *((uint32_t *) addr) = mask & 0xFE; |
| bogdanm | 15:4892fe388435 | 417 | } |
| bogdanm | 15:4892fe388435 | 418 | } |
