Fixed Incorrect pressure readings for the barometer
Fork of MS5637 by
ms5637.cpp@9:83b2554646f5, 2016-06-15 (annotated)
- Committer:
- cam_eadie
- Date:
- Wed Jun 15 14:45:25 2016 +0000
- Revision:
- 9:83b2554646f5
- Parent:
- 8:3a9d37268ccd
Fixed incorrect pressure reading using some float convesions, cleaning up and simplifying code in calcPT()
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
loopsva | 0:f97f410d4a21 | 1 | //! |
loopsva | 0:f97f410d4a21 | 2 | //! @file an520_I2C.c,v |
loopsva | 0:f97f410d4a21 | 3 | //! |
loopsva | 0:f97f410d4a21 | 4 | //! Copyright (c) 2009 MEAS Switzerland |
loopsva | 0:f97f410d4a21 | 5 | //! |
loopsva | 0:f97f410d4a21 | 6 | //! |
loopsva | 0:f97f410d4a21 | 7 | //! |
loopsva | 0:f97f410d4a21 | 8 | //! @brief This C code is for starter reference only. It is written for the |
loopsva | 0:f97f410d4a21 | 9 | //! MEAS Switzerland MS56xx pressure sensor modules and Atmel Atmega644p |
loopsva | 0:f97f410d4a21 | 10 | //! microcontroller. |
loopsva | 0:f97f410d4a21 | 11 | //! |
loopsva | 0:f97f410d4a21 | 12 | //! @version 1.0 $Id: an520_I2C.c,v 1.0 |
loopsva | 0:f97f410d4a21 | 13 | //! |
loopsva | 0:f97f410d4a21 | 14 | //! @todo |
loopsva | 0:f97f410d4a21 | 15 | |
loopsva | 0:f97f410d4a21 | 16 | #include "mbed.h" |
cstevens | 8:3a9d37268ccd | 17 | #include "ms5637.h" |
cam_eadie | 9:83b2554646f5 | 18 | //Serial pc2(USBTX, USBRX); |
loopsva | 0:f97f410d4a21 | 19 | |
loopsva | 5:0d7b229474c6 | 20 | double P; // compensated pressure value (mB) |
loopsva | 5:0d7b229474c6 | 21 | double T; // compensated temperature value (degC) |
loopsva | 5:0d7b229474c6 | 22 | double A; // altitude (ft) |
loopsva | 5:0d7b229474c6 | 23 | double S; // sea level barometer (mB) |
loopsva | 2:05804ed70748 | 24 | |
loopsva | 2:05804ed70748 | 25 | uint32_t C[8]; //coefficient storage |
loopsva | 2:05804ed70748 | 26 | |
loopsva | 0:f97f410d4a21 | 27 | //--------------------------------------------------------------------------------------------------------------------------------------// |
loopsva | 0:f97f410d4a21 | 28 | // Constructor and destructor |
loopsva | 0:f97f410d4a21 | 29 | |
cstevens | 8:3a9d37268ccd | 30 | ms5637::ms5637(PinName sda, PinName scl) : _i2c(sda, scl) { |
loopsva | 6:41c370fa1f7b | 31 | _i2c.frequency(400000); |
loopsva | 0:f97f410d4a21 | 32 | } |
loopsva | 0:f97f410d4a21 | 33 | |
loopsva | 0:f97f410d4a21 | 34 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 35 | //! @brief send I2C start condition and the address byte |
loopsva | 0:f97f410d4a21 | 36 | //! |
loopsva | 0:f97f410d4a21 | 37 | //! @return 0 |
loopsva | 0:f97f410d4a21 | 38 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 39 | |
cstevens | 8:3a9d37268ccd | 40 | int ms5637::m_i2c_start(bool readMode) { |
loopsva | 0:f97f410d4a21 | 41 | int twst; |
loopsva | 0:f97f410d4a21 | 42 | _i2c.start(); |
loopsva | 0:f97f410d4a21 | 43 | if(readMode == true) { |
cstevens | 8:3a9d37268ccd | 44 | twst = m_i2c_write(MS5637_ADDR_R); |
loopsva | 0:f97f410d4a21 | 45 | } else { |
cstevens | 8:3a9d37268ccd | 46 | twst = m_i2c_write(MS5637_ADDR_W); |
loopsva | 0:f97f410d4a21 | 47 | } |
loopsva | 0:f97f410d4a21 | 48 | return(twst); |
loopsva | 0:f97f410d4a21 | 49 | } |
loopsva | 0:f97f410d4a21 | 50 | |
loopsva | 0:f97f410d4a21 | 51 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 52 | //! @brief send I2C stop condition |
loopsva | 0:f97f410d4a21 | 53 | //! |
loopsva | 0:f97f410d4a21 | 54 | //! @return none |
loopsva | 0:f97f410d4a21 | 55 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 56 | |
cstevens | 8:3a9d37268ccd | 57 | void ms5637::m_i2c_stop(void) { |
loopsva | 0:f97f410d4a21 | 58 | _i2c.stop(); |
loopsva | 0:f97f410d4a21 | 59 | } |
loopsva | 0:f97f410d4a21 | 60 | |
loopsva | 0:f97f410d4a21 | 61 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 62 | //! @brief send I2C stop condition |
loopsva | 0:f97f410d4a21 | 63 | //! |
loopsva | 0:f97f410d4a21 | 64 | //! @return remote ack status |
loopsva | 0:f97f410d4a21 | 65 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 66 | |
cstevens | 8:3a9d37268ccd | 67 | unsigned char ms5637::m_i2c_write(unsigned char data) { |
loopsva | 0:f97f410d4a21 | 68 | int twst = _i2c.write(data); |
loopsva | 0:f97f410d4a21 | 69 | return(twst); |
loopsva | 0:f97f410d4a21 | 70 | } |
loopsva | 0:f97f410d4a21 | 71 | |
loopsva | 0:f97f410d4a21 | 72 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 73 | //! @brief read I2C byte with acknowledgment |
loopsva | 0:f97f410d4a21 | 74 | //! |
loopsva | 0:f97f410d4a21 | 75 | //! @return read byte |
loopsva | 0:f97f410d4a21 | 76 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 77 | |
cstevens | 8:3a9d37268ccd | 78 | unsigned char ms5637::m_i2c_readAck(void) { |
loopsva | 0:f97f410d4a21 | 79 | int twst = _i2c.read(1); |
loopsva | 0:f97f410d4a21 | 80 | return(twst); |
loopsva | 0:f97f410d4a21 | 81 | } |
loopsva | 0:f97f410d4a21 | 82 | |
loopsva | 0:f97f410d4a21 | 83 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 84 | //! @brief read I2C byte without acknowledgment |
loopsva | 0:f97f410d4a21 | 85 | //! |
loopsva | 0:f97f410d4a21 | 86 | //! @return read byte |
loopsva | 0:f97f410d4a21 | 87 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 88 | |
cstevens | 8:3a9d37268ccd | 89 | unsigned char ms5637::m_i2c_readNak(void) { |
loopsva | 0:f97f410d4a21 | 90 | int twst = _i2c.read(0); |
loopsva | 0:f97f410d4a21 | 91 | return(twst); |
loopsva | 0:f97f410d4a21 | 92 | } |
loopsva | 0:f97f410d4a21 | 93 | |
loopsva | 0:f97f410d4a21 | 94 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 95 | //! @brief send command using I2C hardware interface |
loopsva | 0:f97f410d4a21 | 96 | //! |
loopsva | 0:f97f410d4a21 | 97 | //! @return none |
loopsva | 0:f97f410d4a21 | 98 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 99 | |
cstevens | 8:3a9d37268ccd | 100 | void ms5637::m_i2c_send(char cmd) { |
loopsva | 0:f97f410d4a21 | 101 | unsigned char ret; |
loopsva | 2:05804ed70748 | 102 | ret = m_i2c_start(false); |
loopsva | 2:05804ed70748 | 103 | if(!(ret)) { |
loopsva | 0:f97f410d4a21 | 104 | m_i2c_stop(); |
loopsva | 2:05804ed70748 | 105 | } else { |
loopsva | 0:f97f410d4a21 | 106 | ret = m_i2c_write(cmd); |
loopsva | 0:f97f410d4a21 | 107 | m_i2c_stop(); |
loopsva | 0:f97f410d4a21 | 108 | } |
loopsva | 0:f97f410d4a21 | 109 | } |
loopsva | 0:f97f410d4a21 | 110 | |
loopsva | 0:f97f410d4a21 | 111 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 112 | //! @brief send reset sequence |
loopsva | 0:f97f410d4a21 | 113 | //! |
loopsva | 0:f97f410d4a21 | 114 | //! @return none |
loopsva | 0:f97f410d4a21 | 115 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 116 | |
cstevens | 8:3a9d37268ccd | 117 | void ms5637::cmd_reset() { |
cstevens | 8:3a9d37268ccd | 118 | m_i2c_send(MS5637_CMD_RESET); |
loopsva | 2:05804ed70748 | 119 | wait_ms(4); |
loopsva | 0:f97f410d4a21 | 120 | loadCoefs(); |
loopsva | 0:f97f410d4a21 | 121 | } |
loopsva | 0:f97f410d4a21 | 122 | |
loopsva | 0:f97f410d4a21 | 123 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 124 | //! @brief preform adc conversion |
loopsva | 0:f97f410d4a21 | 125 | //! |
loopsva | 0:f97f410d4a21 | 126 | //! @return 24bit result |
loopsva | 0:f97f410d4a21 | 127 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 128 | |
cstevens | 8:3a9d37268ccd | 129 | unsigned long ms5637::cmd_adc(char cmd) { |
loopsva | 0:f97f410d4a21 | 130 | char cobuf[3]; |
loopsva | 0:f97f410d4a21 | 131 | cobuf[0] = 0; |
loopsva | 0:f97f410d4a21 | 132 | cobuf[1] = 0; |
loopsva | 0:f97f410d4a21 | 133 | cobuf[2] = 0; |
loopsva | 0:f97f410d4a21 | 134 | unsigned int ret; |
loopsva | 0:f97f410d4a21 | 135 | unsigned long temp = 0; |
cstevens | 8:3a9d37268ccd | 136 | m_i2c_send(MS5637_CMD_ADC_CONV + cmd); |
loopsva | 2:05804ed70748 | 137 | switch (cmd & 0x0f) { |
cstevens | 8:3a9d37268ccd | 138 | case MS5637_CMD_ADC_256 : wait_us(900); break; |
cstevens | 8:3a9d37268ccd | 139 | case MS5637_CMD_ADC_512 : wait_ms(3); break; |
cstevens | 8:3a9d37268ccd | 140 | case MS5637_CMD_ADC_1024: wait_ms(4); break; |
cstevens | 8:3a9d37268ccd | 141 | case MS5637_CMD_ADC_2048: wait_ms(6); break; |
cstevens | 8:3a9d37268ccd | 142 | case MS5637_CMD_ADC_4096: wait_ms(10); break; |
loopsva | 0:f97f410d4a21 | 143 | } |
cstevens | 8:3a9d37268ccd | 144 | m_i2c_send(MS5637_CMD_ADC_READ); |
loopsva | 0:f97f410d4a21 | 145 | |
cstevens | 8:3a9d37268ccd | 146 | ret = _i2c.read(MS5637_ADDR_R, cobuf, 3, false); |
cstevens | 8:3a9d37268ccd | 147 | if(ret) printf("\n*** ms5637 ADC Read Error "); |
loopsva | 0:f97f410d4a21 | 148 | temp = (cobuf[0] << 16) + (cobuf[1] << 8) + cobuf[2]; |
loopsva | 0:f97f410d4a21 | 149 | return temp; |
loopsva | 0:f97f410d4a21 | 150 | } |
loopsva | 0:f97f410d4a21 | 151 | |
loopsva | 0:f97f410d4a21 | 152 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 153 | //! @brief Read calibration coefficients |
loopsva | 0:f97f410d4a21 | 154 | //! |
loopsva | 0:f97f410d4a21 | 155 | //! @return coefficient |
loopsva | 0:f97f410d4a21 | 156 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 157 | |
cstevens | 8:3a9d37268ccd | 158 | unsigned int ms5637::cmd_prom(char coef_num) { |
loopsva | 0:f97f410d4a21 | 159 | char cobuf[2]; |
loopsva | 0:f97f410d4a21 | 160 | unsigned int ret; |
loopsva | 0:f97f410d4a21 | 161 | unsigned int rC = 0; |
loopsva | 0:f97f410d4a21 | 162 | cobuf[0] = 0; |
loopsva | 0:f97f410d4a21 | 163 | cobuf[1] = 0; |
cstevens | 8:3a9d37268ccd | 164 | m_i2c_send(MS5637_CMD_PROM_RD + coef_num * 2); // send PROM READ command |
cstevens | 8:3a9d37268ccd | 165 | ret = _i2c.read(MS5637_ADDR_R, cobuf, 2, false); |
cstevens | 8:3a9d37268ccd | 166 | if(ret) printf("\n*** ms5637 PROM Read Error "); |
loopsva | 0:f97f410d4a21 | 167 | rC = cobuf[0] * 256 + cobuf[1]; |
loopsva | 0:f97f410d4a21 | 168 | return rC; |
loopsva | 0:f97f410d4a21 | 169 | } |
loopsva | 0:f97f410d4a21 | 170 | |
loopsva | 0:f97f410d4a21 | 171 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 172 | //! @brief calculate the CRC code |
loopsva | 0:f97f410d4a21 | 173 | //! |
loopsva | 0:f97f410d4a21 | 174 | //! @return crc code |
loopsva | 0:f97f410d4a21 | 175 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 176 | |
cstevens | 8:3a9d37268ccd | 177 | unsigned char ms5637::crc4(unsigned int n_prom[]) { |
loopsva | 2:05804ed70748 | 178 | unsigned int n_rem; |
loopsva | 2:05804ed70748 | 179 | unsigned int crc_read; |
loopsva | 0:f97f410d4a21 | 180 | unsigned char n_bit; |
loopsva | 0:f97f410d4a21 | 181 | n_rem = 0x00; |
loopsva | 2:05804ed70748 | 182 | crc_read = n_prom[7]; |
loopsva | 2:05804ed70748 | 183 | n_prom[7]=(0xFF00 & (n_prom[7])); |
loopsva | 2:05804ed70748 | 184 | for (int cnt = 0; cnt < 16; cnt++) { |
loopsva | 0:f97f410d4a21 | 185 | if (cnt%2 == 1) { |
loopsva | 0:f97f410d4a21 | 186 | n_rem ^= (unsigned short) ((n_prom[cnt>>1]) & 0x00FF); |
loopsva | 0:f97f410d4a21 | 187 | } else { |
loopsva | 0:f97f410d4a21 | 188 | n_rem ^= (unsigned short) (n_prom[cnt>>1]>>8); |
loopsva | 0:f97f410d4a21 | 189 | } |
loopsva | 0:f97f410d4a21 | 190 | for (n_bit = 8; n_bit > 0; n_bit--) { |
loopsva | 0:f97f410d4a21 | 191 | if (n_rem & (0x8000)) { |
loopsva | 0:f97f410d4a21 | 192 | n_rem = (n_rem << 1) ^ 0x3000; |
loopsva | 0:f97f410d4a21 | 193 | } else { |
loopsva | 0:f97f410d4a21 | 194 | n_rem = (n_rem << 1); |
loopsva | 0:f97f410d4a21 | 195 | } |
loopsva | 0:f97f410d4a21 | 196 | } |
loopsva | 0:f97f410d4a21 | 197 | } |
loopsva | 2:05804ed70748 | 198 | n_rem= (0x000F & (n_rem >> 12)); |
loopsva | 2:05804ed70748 | 199 | n_prom[7]=crc_read; |
loopsva | 0:f97f410d4a21 | 200 | return (n_rem ^ 0x0); |
loopsva | 2:05804ed70748 | 201 | } |
loopsva | 2:05804ed70748 | 202 | |
loopsva | 0:f97f410d4a21 | 203 | /* |
loopsva | 0:f97f410d4a21 | 204 | The CRC code is calculated and written in factory with the LSB byte in the prom n_prom[7] set to 0x00 (see |
loopsva | 0:f97f410d4a21 | 205 | Coefficient table below). It is thus important to clear those bytes from the calculation buffer before proceeding |
loopsva | 0:f97f410d4a21 | 206 | with the CRC calculation itself: |
loopsva | 0:f97f410d4a21 | 207 | n_prom[7]=(0xFF00 & (n_prom[7])); //CRC byte is replaced by 0 |
loopsva | 0:f97f410d4a21 | 208 | As a simple test of the CRC code, the following coefficient table could be used: |
loopsva | 0:f97f410d4a21 | 209 | unsigned int nprom[] = {0x3132,0x3334,0x3536,0x3738,0x3940,0x4142,0x4344,0x4500}; |
loopsva | 0:f97f410d4a21 | 210 | the resulting calculated CRC should be 0xB. |
loopsva | 0:f97f410d4a21 | 211 | |
loopsva | 0:f97f410d4a21 | 212 | DB 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 |
loopsva | 0:f97f410d4a21 | 213 | Addr |
loopsva | 0:f97f410d4a21 | 214 | 0 16 bit reserved for manufacturer |
loopsva | 0:f97f410d4a21 | 215 | 1 Coefficient 1 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 216 | 2 Coefficient 2 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 217 | 3 Coefficient 3 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 218 | 4 Coefficient 4 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 219 | 5 Coefficient 5 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 220 | 6 Coefficient 6 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 221 | 7 0 0 0 0 CRC(0x0) |
loopsva | 0:f97f410d4a21 | 222 | */ |
loopsva | 0:f97f410d4a21 | 223 | /* |
loopsva | 0:f97f410d4a21 | 224 | //Returns 0x0b as per AP520_004 |
loopsva | 2:05804ed70748 | 225 | C[0] = 0x3132; |
loopsva | 2:05804ed70748 | 226 | C[1] = 0x3334; |
loopsva | 2:05804ed70748 | 227 | C[2] = 0x3536; |
loopsva | 2:05804ed70748 | 228 | C[3] = 0x3738; |
loopsva | 2:05804ed70748 | 229 | C[4] = 0x3940; |
loopsva | 2:05804ed70748 | 230 | C[5] = 0x4142; |
loopsva | 2:05804ed70748 | 231 | C[6] = 0x4344; |
loopsva | 2:05804ed70748 | 232 | C[7] = 0x4546; |
loopsva | 0:f97f410d4a21 | 233 | n_crc = ms.crc4(C); // calculate the CRC |
loopsva | 0:f97f410d4a21 | 234 | pc.printf("testing CRC: 0x%x\n", n_crc); |
loopsva | 0:f97f410d4a21 | 235 | */ |
loopsva | 2:05804ed70748 | 236 | |
loopsva | 0:f97f410d4a21 | 237 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 238 | //! @brief load all calibration coefficients |
loopsva | 0:f97f410d4a21 | 239 | //! |
loopsva | 0:f97f410d4a21 | 240 | //! @return none |
loopsva | 0:f97f410d4a21 | 241 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 242 | |
cstevens | 8:3a9d37268ccd | 243 | void ms5637::loadCoefs() { |
loopsva | 0:f97f410d4a21 | 244 | for (int i = 0; i < 8; i++){ |
loopsva | 0:f97f410d4a21 | 245 | wait_ms(50); |
loopsva | 2:05804ed70748 | 246 | C[i] = cmd_prom(i); |
loopsva | 0:f97f410d4a21 | 247 | } |
loopsva | 2:05804ed70748 | 248 | unsigned char n_crc = crc4(C); |
loopsva | 0:f97f410d4a21 | 249 | } |
loopsva | 0:f97f410d4a21 | 250 | |
loopsva | 0:f97f410d4a21 | 251 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 252 | //! @brief calculate temperature and pressure |
loopsva | 0:f97f410d4a21 | 253 | //! |
loopsva | 0:f97f410d4a21 | 254 | //! @return none |
loopsva | 0:f97f410d4a21 | 255 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 256 | |
cstevens | 8:3a9d37268ccd | 257 | void ms5637::calcPT() { |
cstevens | 8:3a9d37268ccd | 258 | int32_t D2 = cmd_adc(MS5637_CMD_ADC_D2 + MS5637_CMD_ADC_4096); // read D2 |
cstevens | 8:3a9d37268ccd | 259 | int32_t D1 = cmd_adc(MS5637_CMD_ADC_D1 + MS5637_CMD_ADC_4096); // read D1 |
loopsva | 2:05804ed70748 | 260 | |
cam_eadie | 9:83b2554646f5 | 261 | float dT = (float)D2 - ((float)C[5] * 256.0); |
cam_eadie | 9:83b2554646f5 | 262 | float TEMP = 2000.0 + (dT*(float)C[6])/8388608.0; |
cam_eadie | 9:83b2554646f5 | 263 | |
cam_eadie | 9:83b2554646f5 | 264 | float OFF = ((float)C[2] * 131072.0 + (dT * (float)C[4])/64.0); |
cam_eadie | 9:83b2554646f5 | 265 | float SENS = ((float)C[1] * 65536.0)+ ((dT * ((float)C[3]) /128.0)); |
cam_eadie | 9:83b2554646f5 | 266 | |
cam_eadie | 9:83b2554646f5 | 267 | // Commented out serial pc2 at start of code so you can check raw values |
cam_eadie | 9:83b2554646f5 | 268 | //pc2.printf("D1: %d\r\nD2: %d\r\nC1: %d\r\nC2: %d\r\nC3: %d\r\nC4: %d\r\nC5: %d\r\nC6: %d\r\n", D1, D2, C[1], C[2], C[3], C[4], C[5], C[6]); |
cam_eadie | 9:83b2554646f5 | 269 | //pc2.printf("OFF: %f\r\nSENS: %f\r\n",OFF, SENS); |
cam_eadie | 9:83b2554646f5 | 270 | |
cam_eadie | 9:83b2554646f5 | 271 | if(TEMP < 2000) { // if temperature lower than 20 Celsius |
cam_eadie | 9:83b2554646f5 | 272 | float T1 = (TEMP - 2000.0) * (TEMP - 2000.0); |
cam_eadie | 9:83b2554646f5 | 273 | float OFF1 = (61.0 * T1) / 16.0; |
cam_eadie | 9:83b2554646f5 | 274 | float SENS1 = (29.0 * T1) / 16.0; |
cam_eadie | 9:83b2554646f5 | 275 | |
loopsva | 2:05804ed70748 | 276 | if(TEMP < -1500) { // if temperature lower than -15 Celsius |
cam_eadie | 9:83b2554646f5 | 277 | T1 = (TEMP + 1500.0) * (TEMP + 1500.0); |
cam_eadie | 9:83b2554646f5 | 278 | OFF1 += 17.0 * T1; |
cam_eadie | 9:83b2554646f5 | 279 | SENS1 += 9.0 * T1 ; |
loopsva | 2:05804ed70748 | 280 | } |
loopsva | 2:05804ed70748 | 281 | OFF -= OFF1; |
loopsva | 2:05804ed70748 | 282 | SENS -= SENS1; |
loopsva | 2:05804ed70748 | 283 | } |
cam_eadie | 9:83b2554646f5 | 284 | T = TEMP / 100.0; |
cam_eadie | 9:83b2554646f5 | 285 | P = ((D1*(SENS / 2097152.0)-OFF)/32768.0)/100.0; |
loopsva | 0:f97f410d4a21 | 286 | } |
loopsva | 0:f97f410d4a21 | 287 | |
loopsva | 0:f97f410d4a21 | 288 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 289 | //! @brief calculate temperature |
loopsva | 0:f97f410d4a21 | 290 | //! |
loopsva | 0:f97f410d4a21 | 291 | //! @return double temperature degC |
loopsva | 0:f97f410d4a21 | 292 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 293 | |
cstevens | 8:3a9d37268ccd | 294 | double ms5637::calcTemp() { |
loopsva | 0:f97f410d4a21 | 295 | calcPT(); |
loopsva | 0:f97f410d4a21 | 296 | return(T); |
loopsva | 0:f97f410d4a21 | 297 | } |
loopsva | 0:f97f410d4a21 | 298 | |
loopsva | 0:f97f410d4a21 | 299 | //******************************************************** |
loopsva | 3:c2d1b0d432ad | 300 | //! @brief calculate pressure |
loopsva | 0:f97f410d4a21 | 301 | //! |
loopsva | 0:f97f410d4a21 | 302 | //! @return double barometric pressure millibar |
loopsva | 0:f97f410d4a21 | 303 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 304 | |
cstevens | 8:3a9d37268ccd | 305 | double ms5637::calcPressure() { |
loopsva | 0:f97f410d4a21 | 306 | calcPT(); |
loopsva | 0:f97f410d4a21 | 307 | return(P); |
loopsva | 2:05804ed70748 | 308 | } |
loopsva | 3:c2d1b0d432ad | 309 | |
loopsva | 3:c2d1b0d432ad | 310 | //******************************************************** |
loopsva | 3:c2d1b0d432ad | 311 | //! @brief get pressure, no calculation |
loopsva | 3:c2d1b0d432ad | 312 | //! |
loopsva | 3:c2d1b0d432ad | 313 | //! @return double barometric pressure millibar |
loopsva | 3:c2d1b0d432ad | 314 | //******************************************************** |
loopsva | 3:c2d1b0d432ad | 315 | |
cstevens | 8:3a9d37268ccd | 316 | double ms5637::getPressure() { |
loopsva | 3:c2d1b0d432ad | 317 | calcPT(); |
loopsva | 3:c2d1b0d432ad | 318 | return(P); |
loopsva | 3:c2d1b0d432ad | 319 | } |
loopsva | 3:c2d1b0d432ad | 320 | |
loopsva | 3:c2d1b0d432ad | 321 | //******************************************************** |
loopsva | 5:0d7b229474c6 | 322 | //! @brief get altitude from known sea level barometer, |
loopsva | 5:0d7b229474c6 | 323 | //! @ no pre-pressure calculation |
loopsva | 3:c2d1b0d432ad | 324 | //! |
loopsva | 3:c2d1b0d432ad | 325 | //! @enter float sea level barometer |
loopsva | 3:c2d1b0d432ad | 326 | //! @return float altitude in feet |
loopsva | 3:c2d1b0d432ad | 327 | //******************************************************** |
loopsva | 3:c2d1b0d432ad | 328 | |
cstevens | 8:3a9d37268ccd | 329 | float ms5637::getAltitudeFT(float sea_pressure) { |
loopsva | 3:c2d1b0d432ad | 330 | A = (1 - (pow((P / (double)sea_pressure), 0.190284))) * 145366.45; |
loopsva | 3:c2d1b0d432ad | 331 | return((float)A); |
loopsva | 3:c2d1b0d432ad | 332 | } |
loopsva | 5:0d7b229474c6 | 333 | |
loopsva | 5:0d7b229474c6 | 334 | //******************************************************** |
loopsva | 5:0d7b229474c6 | 335 | //! @brief get sea level pressure from known altitude(ft), |
loopsva | 5:0d7b229474c6 | 336 | //! @ no pre-pressure calculation |
loopsva | 5:0d7b229474c6 | 337 | //! |
loopsva | 5:0d7b229474c6 | 338 | //! @enter float known altitude in feet |
loopsva | 5:0d7b229474c6 | 339 | //! @return float seal level barometer in mb |
loopsva | 5:0d7b229474c6 | 340 | //******************************************************** |
loopsva | 5:0d7b229474c6 | 341 | |
cstevens | 8:3a9d37268ccd | 342 | float ms5637::getSeaLevelBaroFT(float known_alt) { |
loopsva | 5:0d7b229474c6 | 343 | S = pow(pow((P * INHG), 0.190284) + 0.00001313 * known_alt , 5.2553026) * MB; |
loopsva | 5:0d7b229474c6 | 344 | return((float)S); |
loopsva | 5:0d7b229474c6 | 345 | } |
loopsva | 5:0d7b229474c6 | 346 | |
loopsva | 5:0d7b229474c6 | 347 | //******************************************************** |
loopsva | 5:0d7b229474c6 | 348 | //! @brief get sea level pressure from known altitude(m), |
loopsva | 5:0d7b229474c6 | 349 | //! @ no pre-pressure calculation |
loopsva | 5:0d7b229474c6 | 350 | //! |
loopsva | 5:0d7b229474c6 | 351 | //! @enter float known altitude in meters |
loopsva | 5:0d7b229474c6 | 352 | //! @return float seal level barometer in mb |
loopsva | 5:0d7b229474c6 | 353 | //******************************************************** |
loopsva | 5:0d7b229474c6 | 354 | |
cstevens | 8:3a9d37268ccd | 355 | float ms5637::getSeaLevelBaroM(float known_alt) { |
loopsva | 5:0d7b229474c6 | 356 | S = pow(pow((P * INHG), 0.190284) + 0.00001313 * known_alt * FTMETERS , 5.2553026) * MB; |
loopsva | 5:0d7b229474c6 | 357 | return((float)S); |
loopsva | 5:0d7b229474c6 | 358 | } |