BMP180
Fork of BMP180 by
BMP180.cpp@0:b2219e6e444b, 2015-04-17 (annotated)
- Committer:
- kgills
- Date:
- Fri Apr 17 09:31:09 2015 -0500
- Revision:
- 0:b2219e6e444b
- Child:
- 1:817fb4e66714
Adding BMP180 library files.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
kgills |
0:b2219e6e444b | 1 | /******************************************************************************* |
kgills |
0:b2219e6e444b | 2 | * Copyright (C) 2015 Maxim Integrated Products, Inc., All Rights Reserved. |
kgills |
0:b2219e6e444b | 3 | * |
kgills |
0:b2219e6e444b | 4 | * Permission is hereby granted, free of charge, to any person obtaining a |
kgills |
0:b2219e6e444b | 5 | * copy of this software and associated documentation files (the "Software"), |
kgills |
0:b2219e6e444b | 6 | * to deal in the Software without restriction, including without limitation |
kgills |
0:b2219e6e444b | 7 | * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
kgills |
0:b2219e6e444b | 8 | * and/or sell copies of the Software, and to permit persons to whom the |
kgills |
0:b2219e6e444b | 9 | * Software is furnished to do so, subject to the following conditions: |
kgills |
0:b2219e6e444b | 10 | * |
kgills |
0:b2219e6e444b | 11 | * The above copyright notice and this permission notice shall be included |
kgills |
0:b2219e6e444b | 12 | * in all copies or substantial portions of the Software. |
kgills |
0:b2219e6e444b | 13 | * |
kgills |
0:b2219e6e444b | 14 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
kgills |
0:b2219e6e444b | 15 | * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
kgills |
0:b2219e6e444b | 16 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. |
kgills |
0:b2219e6e444b | 17 | * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES |
kgills |
0:b2219e6e444b | 18 | * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, |
kgills |
0:b2219e6e444b | 19 | * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR |
kgills |
0:b2219e6e444b | 20 | * OTHER DEALINGS IN THE SOFTWARE. |
kgills |
0:b2219e6e444b | 21 | * |
kgills |
0:b2219e6e444b | 22 | * Except as contained in this notice, the name of Maxim Integrated |
kgills |
0:b2219e6e444b | 23 | * Products, Inc. shall not be used except as stated in the Maxim Integrated |
kgills |
0:b2219e6e444b | 24 | * Products, Inc. Branding Policy. |
kgills |
0:b2219e6e444b | 25 | * |
kgills |
0:b2219e6e444b | 26 | * The mere transfer of this software does not imply any licenses |
kgills |
0:b2219e6e444b | 27 | * of trade secrets, proprietary technology, copyrights, patents, |
kgills |
0:b2219e6e444b | 28 | * trademarks, maskwork rights, or any other form of intellectual |
kgills |
0:b2219e6e444b | 29 | * property whatsoever. Maxim Integrated Products, Inc. retains all |
kgills |
0:b2219e6e444b | 30 | * ownership rights. |
kgills |
0:b2219e6e444b | 31 | ******************************************************************************* |
kgills |
0:b2219e6e444b | 32 | */ |
kgills |
0:b2219e6e444b | 33 | |
kgills |
0:b2219e6e444b | 34 | #include "BMP180.h" |
kgills |
0:b2219e6e444b | 35 | |
kgills |
0:b2219e6e444b | 36 | /***** Definitions *****/ |
kgills |
0:b2219e6e444b | 37 | #define I2C_ADDR (0xEE) // 1110111x |
kgills |
0:b2219e6e444b | 38 | |
kgills |
0:b2219e6e444b | 39 | #define REG_ADDR_RESET (0xE0) |
kgills |
0:b2219e6e444b | 40 | #define REG_ADDR_ID (0xD0) |
kgills |
0:b2219e6e444b | 41 | #define REG_ADDR_CTRL (0xF4) |
kgills |
0:b2219e6e444b | 42 | #define REG_ADDR_DATA (0xF6) |
kgills |
0:b2219e6e444b | 43 | #define REG_ADDR_AC1 (0xAA) |
kgills |
0:b2219e6e444b | 44 | |
kgills |
0:b2219e6e444b | 45 | #define CTRL_REG_TEMP (0x2E) |
kgills |
0:b2219e6e444b | 46 | #define CTRL_REG_PRESS_0 (0x34) |
kgills |
0:b2219e6e444b | 47 | #define CTRL_REG_PRESS_1 (0x74) |
kgills |
0:b2219e6e444b | 48 | #define CTRL_REG_PRESS_2 (0xB4) |
kgills |
0:b2219e6e444b | 49 | #define CTRL_REG_PRESS_3 (0xF4) |
kgills |
0:b2219e6e444b | 50 | |
kgills |
0:b2219e6e444b | 51 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 52 | BMP180::BMP180(PinName sda, PinName scl) |
kgills |
0:b2219e6e444b | 53 | { |
kgills |
0:b2219e6e444b | 54 | i2c_ = new I2C(sda, scl); |
kgills |
0:b2219e6e444b | 55 | i2c_owner = true; |
kgills |
0:b2219e6e444b | 56 | |
kgills |
0:b2219e6e444b | 57 | i2c_->frequency(400000); |
kgills |
0:b2219e6e444b | 58 | } |
kgills |
0:b2219e6e444b | 59 | |
kgills |
0:b2219e6e444b | 60 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 61 | BMP180::BMP180(I2C *i2c) : |
kgills |
0:b2219e6e444b | 62 | i2c_(i2c) |
kgills |
0:b2219e6e444b | 63 | { |
kgills |
0:b2219e6e444b | 64 | i2c_owner = false; |
kgills |
0:b2219e6e444b | 65 | } |
kgills |
0:b2219e6e444b | 66 | |
kgills |
0:b2219e6e444b | 67 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 68 | BMP180::~BMP180() |
kgills |
0:b2219e6e444b | 69 | { |
kgills |
0:b2219e6e444b | 70 | if(i2c_owner) { |
kgills |
0:b2219e6e444b | 71 | delete i2c_; |
kgills |
0:b2219e6e444b | 72 | } |
kgills |
0:b2219e6e444b | 73 | } |
kgills |
0:b2219e6e444b | 74 | |
kgills |
0:b2219e6e444b | 75 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 76 | int BMP180::init(void) |
kgills |
0:b2219e6e444b | 77 | { |
kgills |
0:b2219e6e444b | 78 | char addr; |
kgills |
0:b2219e6e444b | 79 | char data[22]; |
kgills |
0:b2219e6e444b | 80 | int i; |
kgills |
0:b2219e6e444b | 81 | |
kgills |
0:b2219e6e444b | 82 | if (checkId() != 0) { |
kgills |
0:b2219e6e444b | 83 | return -1; |
kgills |
0:b2219e6e444b | 84 | } |
kgills |
0:b2219e6e444b | 85 | |
kgills |
0:b2219e6e444b | 86 | addr = REG_ADDR_AC1; |
kgills |
0:b2219e6e444b | 87 | if (i2c_->write(I2C_ADDR, &addr, 1) != 0) { |
kgills |
0:b2219e6e444b | 88 | return -1; |
kgills |
0:b2219e6e444b | 89 | } |
kgills |
0:b2219e6e444b | 90 | |
kgills |
0:b2219e6e444b | 91 | if (i2c_->read(I2C_ADDR, data, 22) != 0) { |
kgills |
0:b2219e6e444b | 92 | return -1; |
kgills |
0:b2219e6e444b | 93 | } |
kgills |
0:b2219e6e444b | 94 | |
kgills |
0:b2219e6e444b | 95 | for (i = 0; i < 11; i++) { |
kgills |
0:b2219e6e444b | 96 | calib.value[i] = (data[2*i] << 8) | data[(2*i)+1]; |
kgills |
0:b2219e6e444b | 97 | } |
kgills |
0:b2219e6e444b | 98 | |
kgills |
0:b2219e6e444b | 99 | return 0; |
kgills |
0:b2219e6e444b | 100 | } |
kgills |
0:b2219e6e444b | 101 | |
kgills |
0:b2219e6e444b | 102 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 103 | int BMP180::reset(void) |
kgills |
0:b2219e6e444b | 104 | { |
kgills |
0:b2219e6e444b | 105 | char data; |
kgills |
0:b2219e6e444b | 106 | |
kgills |
0:b2219e6e444b | 107 | data = REG_ADDR_RESET; |
kgills |
0:b2219e6e444b | 108 | if (i2c_->write(I2C_ADDR, &data, 1) != 0) { |
kgills |
0:b2219e6e444b | 109 | return -1; |
kgills |
0:b2219e6e444b | 110 | } |
kgills |
0:b2219e6e444b | 111 | |
kgills |
0:b2219e6e444b | 112 | data = 0xB6; |
kgills |
0:b2219e6e444b | 113 | if (i2c_->write(I2C_ADDR, &data, 1) != 0) { |
kgills |
0:b2219e6e444b | 114 | return -1; |
kgills |
0:b2219e6e444b | 115 | } |
kgills |
0:b2219e6e444b | 116 | |
kgills |
0:b2219e6e444b | 117 | return 0; |
kgills |
0:b2219e6e444b | 118 | } |
kgills |
0:b2219e6e444b | 119 | |
kgills |
0:b2219e6e444b | 120 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 121 | int BMP180::checkId(void) |
kgills |
0:b2219e6e444b | 122 | { |
kgills |
0:b2219e6e444b | 123 | char addr; |
kgills |
0:b2219e6e444b | 124 | char data; |
kgills |
0:b2219e6e444b | 125 | |
kgills |
0:b2219e6e444b | 126 | addr = REG_ADDR_ID; |
kgills |
0:b2219e6e444b | 127 | if (i2c_->write(I2C_ADDR, &addr, 1) != 0) { |
kgills |
0:b2219e6e444b | 128 | return -1; |
kgills |
0:b2219e6e444b | 129 | } |
kgills |
0:b2219e6e444b | 130 | |
kgills |
0:b2219e6e444b | 131 | if (i2c_->read(I2C_ADDR, &data, 1) != 0) { |
kgills |
0:b2219e6e444b | 132 | return -1; |
kgills |
0:b2219e6e444b | 133 | } |
kgills |
0:b2219e6e444b | 134 | |
kgills |
0:b2219e6e444b | 135 | if (data != 0x55) { |
kgills |
0:b2219e6e444b | 136 | return -1; |
kgills |
0:b2219e6e444b | 137 | } |
kgills |
0:b2219e6e444b | 138 | |
kgills |
0:b2219e6e444b | 139 | return 0; |
kgills |
0:b2219e6e444b | 140 | } |
kgills |
0:b2219e6e444b | 141 | |
kgills |
0:b2219e6e444b | 142 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 143 | int BMP180::startPressure(BMP180::oversampling_t oss) |
kgills |
0:b2219e6e444b | 144 | { |
kgills |
0:b2219e6e444b | 145 | char data[2]; |
kgills |
0:b2219e6e444b | 146 | |
kgills |
0:b2219e6e444b | 147 | data[0] = REG_ADDR_CTRL; |
kgills |
0:b2219e6e444b | 148 | data[1] = CTRL_REG_PRESS_0 | ((oss & 0x3) << 6); |
kgills |
0:b2219e6e444b | 149 | oss_ = oss; |
kgills |
0:b2219e6e444b | 150 | |
kgills |
0:b2219e6e444b | 151 | if (i2c_->write(I2C_ADDR, data, 2) != 0) { |
kgills |
0:b2219e6e444b | 152 | return -1; |
kgills |
0:b2219e6e444b | 153 | } |
kgills |
0:b2219e6e444b | 154 | |
kgills |
0:b2219e6e444b | 155 | return 0; |
kgills |
0:b2219e6e444b | 156 | } |
kgills |
0:b2219e6e444b | 157 | |
kgills |
0:b2219e6e444b | 158 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 159 | int BMP180::getPressure(int *pressure) |
kgills |
0:b2219e6e444b | 160 | { |
kgills |
0:b2219e6e444b | 161 | char addr, byte[3]; |
kgills |
0:b2219e6e444b | 162 | uint32_t up; |
kgills |
0:b2219e6e444b | 163 | int32_t b6, x1, x2, x3, b3, p; |
kgills |
0:b2219e6e444b | 164 | uint32_t b4, b7; |
kgills |
0:b2219e6e444b | 165 | |
kgills |
0:b2219e6e444b | 166 | addr = REG_ADDR_DATA; |
kgills |
0:b2219e6e444b | 167 | if (i2c_->write(I2C_ADDR, &addr, 1) != 0) { |
kgills |
0:b2219e6e444b | 168 | return -1; |
kgills |
0:b2219e6e444b | 169 | } |
kgills |
0:b2219e6e444b | 170 | |
kgills |
0:b2219e6e444b | 171 | if (i2c_->read(I2C_ADDR, byte, 3) != 0) { |
kgills |
0:b2219e6e444b | 172 | return -1; |
kgills |
0:b2219e6e444b | 173 | } |
kgills |
0:b2219e6e444b | 174 | |
kgills |
0:b2219e6e444b | 175 | up = ((byte[0] << 16) | (byte[1] << 8) | byte[2]) >> (8 - oss_); |
kgills |
0:b2219e6e444b | 176 | |
kgills |
0:b2219e6e444b | 177 | b6 = b5 - 4000; |
kgills |
0:b2219e6e444b | 178 | x1 = (b6 * b6) >> 12; |
kgills |
0:b2219e6e444b | 179 | x1 *= calib.b2; |
kgills |
0:b2219e6e444b | 180 | x1 >>= 11; |
kgills |
0:b2219e6e444b | 181 | x2 = calib.ac2 * b6; |
kgills |
0:b2219e6e444b | 182 | x2 >>= 11; |
kgills |
0:b2219e6e444b | 183 | x3 = x1 + x2; |
kgills |
0:b2219e6e444b | 184 | b3 = (((((int32_t)calib.ac1) * 4 + x3) << oss_) + 2); |
kgills |
0:b2219e6e444b | 185 | b3 >>= 2; |
kgills |
0:b2219e6e444b | 186 | |
kgills |
0:b2219e6e444b | 187 | x1 = (calib.ac3 * b6) >> 13; |
kgills |
0:b2219e6e444b | 188 | x2 = (calib.b1 * ((b6 * b6) >> 12)) >> 16; |
kgills |
0:b2219e6e444b | 189 | x3 = (x1 + x2 + 2) >> 2; |
kgills |
0:b2219e6e444b | 190 | b4 = (calib.ac4 * (uint32_t)(x3 + 32768)) >> 15; |
kgills |
0:b2219e6e444b | 191 | b7 = ((uint32_t)up - b3) * (50000 >> oss_); |
kgills |
0:b2219e6e444b | 192 | p = ((b7 < 0x80000000) ? ((b7 << 1) / b4) : ((b7 / b4) * 2)); |
kgills |
0:b2219e6e444b | 193 | x1 = p >> 8; |
kgills |
0:b2219e6e444b | 194 | x1 *= x1; |
kgills |
0:b2219e6e444b | 195 | x1 = (x1 * 3038) >> 16; |
kgills |
0:b2219e6e444b | 196 | x2 = (-7357 * p) >> 16; |
kgills |
0:b2219e6e444b | 197 | p += (x1 + x2 + 3791) >> 4; |
kgills |
0:b2219e6e444b | 198 | |
kgills |
0:b2219e6e444b | 199 | *pressure = p; |
kgills |
0:b2219e6e444b | 200 | |
kgills |
0:b2219e6e444b | 201 | return 0; |
kgills |
0:b2219e6e444b | 202 | } |
kgills |
0:b2219e6e444b | 203 | |
kgills |
0:b2219e6e444b | 204 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 205 | int BMP180::startTemperature(void) |
kgills |
0:b2219e6e444b | 206 | { |
kgills |
0:b2219e6e444b | 207 | char data[2] = { REG_ADDR_CTRL, CTRL_REG_TEMP }; |
kgills |
0:b2219e6e444b | 208 | |
kgills |
0:b2219e6e444b | 209 | if (i2c_->write(I2C_ADDR, data, 2) != 0) { |
kgills |
0:b2219e6e444b | 210 | return -1; |
kgills |
0:b2219e6e444b | 211 | } |
kgills |
0:b2219e6e444b | 212 | |
kgills |
0:b2219e6e444b | 213 | return 0; |
kgills |
0:b2219e6e444b | 214 | } |
kgills |
0:b2219e6e444b | 215 | |
kgills |
0:b2219e6e444b | 216 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 217 | int BMP180::getTemperature(float *tempC) |
kgills |
0:b2219e6e444b | 218 | { |
kgills |
0:b2219e6e444b | 219 | char addr, byte[2]; |
kgills |
0:b2219e6e444b | 220 | uint16_t ut; |
kgills |
0:b2219e6e444b | 221 | int32_t x1, x2; |
kgills |
0:b2219e6e444b | 222 | |
kgills |
0:b2219e6e444b | 223 | addr = REG_ADDR_DATA; |
kgills |
0:b2219e6e444b | 224 | if (i2c_->write(I2C_ADDR, &addr, 1) != 0) { |
kgills |
0:b2219e6e444b | 225 | return -1; |
kgills |
0:b2219e6e444b | 226 | } |
kgills |
0:b2219e6e444b | 227 | |
kgills |
0:b2219e6e444b | 228 | if (i2c_->read(I2C_ADDR, byte, 2) != 0) { |
kgills |
0:b2219e6e444b | 229 | return -1; |
kgills |
0:b2219e6e444b | 230 | } |
kgills |
0:b2219e6e444b | 231 | |
kgills |
0:b2219e6e444b | 232 | ut = (byte[0] << 8) | byte[1]; |
kgills |
0:b2219e6e444b | 233 | |
kgills |
0:b2219e6e444b | 234 | x1 = ((ut - calib.ac6) * calib.ac5) >> 15; |
kgills |
0:b2219e6e444b | 235 | x2 = (calib.mc << 11) / (x1 + calib.md); |
kgills |
0:b2219e6e444b | 236 | b5 = x1 + x2; |
kgills |
0:b2219e6e444b | 237 | |
kgills |
0:b2219e6e444b | 238 | *tempC = (float)(b5 + 8) / 160; |
kgills |
0:b2219e6e444b | 239 | |
kgills |
0:b2219e6e444b | 240 | return 0; |
kgills |
0:b2219e6e444b | 241 | } |
kgills |
0:b2219e6e444b | 242 | |
kgills |
0:b2219e6e444b | 243 | //****************************************************************************** |
kgills |
0:b2219e6e444b | 244 | int BMP180::getTemperature(int16_t *tempCx10) |
kgills |
0:b2219e6e444b | 245 | { |
kgills |
0:b2219e6e444b | 246 | char addr, byte[2]; |
kgills |
0:b2219e6e444b | 247 | uint16_t ut; |
kgills |
0:b2219e6e444b | 248 | int32_t x1, x2; |
kgills |
0:b2219e6e444b | 249 | |
kgills |
0:b2219e6e444b | 250 | addr = REG_ADDR_DATA; |
kgills |
0:b2219e6e444b | 251 | if (i2c_->write(I2C_ADDR, &addr, 1) != 0) { |
kgills |
0:b2219e6e444b | 252 | return -1; |
kgills |
0:b2219e6e444b | 253 | } |
kgills |
0:b2219e6e444b | 254 | |
kgills |
0:b2219e6e444b | 255 | if (i2c_->read(I2C_ADDR, byte, 2) != 0) { |
kgills |
0:b2219e6e444b | 256 | return -1; |
kgills |
0:b2219e6e444b | 257 | } |
kgills |
0:b2219e6e444b | 258 | |
kgills |
0:b2219e6e444b | 259 | ut = (byte[0] << 8) | byte[1]; |
kgills |
0:b2219e6e444b | 260 | |
kgills |
0:b2219e6e444b | 261 | x1 = ((ut - calib.ac6) * calib.ac5) >> 15; |
kgills |
0:b2219e6e444b | 262 | x2 = (calib.mc << 11) / (x1 + calib.md); |
kgills |
0:b2219e6e444b | 263 | b5 = x1 + x2; |
kgills |
0:b2219e6e444b | 264 | |
kgills |
0:b2219e6e444b | 265 | *tempCx10 = (b5 + 8) >> 4; |
kgills |
0:b2219e6e444b | 266 | |
kgills |
0:b2219e6e444b | 267 | return 0; |
kgills |
0:b2219e6e444b | 268 | } |