High resolution barometer and altimeter using i2c mode
Dependents: upverter_fitbit_clone ReadingMag_HMC5883L_work
ms5611.cpp@9:6104e8cdb3ec, 2015-07-14 (annotated)
- Committer:
- loopsva
- Date:
- Tue Jul 14 16:19:59 2015 +0000
- Revision:
- 9:6104e8cdb3ec
- Parent:
- 8:461f68bc94f2
Fixed minor bugs when using low-level I2C routines. Hi-level I2C routines ok. Also added hooks for the MS5805 (untested).
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" |
loopsva | 0:f97f410d4a21 | 17 | #include "ms5611.h" |
loopsva | 0:f97f410d4a21 | 18 | |
loopsva | 5:0d7b229474c6 | 19 | double P; // compensated pressure value (mB) |
loopsva | 5:0d7b229474c6 | 20 | double T; // compensated temperature value (degC) |
loopsva | 5:0d7b229474c6 | 21 | double A; // altitude (ft) |
loopsva | 5:0d7b229474c6 | 22 | double S; // sea level barometer (mB) |
loopsva | 2:05804ed70748 | 23 | |
loopsva | 2:05804ed70748 | 24 | uint32_t C[8]; //coefficient storage |
loopsva | 9:6104e8cdb3ec | 25 | int MStype = 0; |
loopsva | 2:05804ed70748 | 26 | |
loopsva | 0:f97f410d4a21 | 27 | //--------------------------------------------------------------------------------------------------------------------------------------// |
loopsva | 7:90ee2168baa7 | 28 | // Constructor and destructor - default to be compatible with legacy m5611 driver |
loopsva | 0:f97f410d4a21 | 29 | |
loopsva | 0:f97f410d4a21 | 30 | ms5611::ms5611(PinName sda, PinName scl) : _i2c(sda, scl) { |
loopsva | 6:41c370fa1f7b | 31 | _i2c.frequency(400000); |
loopsva | 7:90ee2168baa7 | 32 | _i2cWAddr = MS5611_ADDR_W; |
loopsva | 7:90ee2168baa7 | 33 | _i2cRAddr = MS5611_ADDR_R; |
loopsva | 7:90ee2168baa7 | 34 | } |
loopsva | 7:90ee2168baa7 | 35 | |
loopsva | 7:90ee2168baa7 | 36 | //--------------------------------------------------------------------------------------------------------------------------------------// |
loopsva | 7:90ee2168baa7 | 37 | // Constructor and destructor - new, to allow for user to select i2c address based on CSB pin |
loopsva | 7:90ee2168baa7 | 38 | |
loopsva | 7:90ee2168baa7 | 39 | ms5611::ms5611(PinName sda, PinName scl, CSBpolarity CSBpin) : _i2c(sda, scl) { |
loopsva | 7:90ee2168baa7 | 40 | _i2c.frequency(400000); |
loopsva | 7:90ee2168baa7 | 41 | _i2cWAddr = MS5611_ADDR_W; |
loopsva | 7:90ee2168baa7 | 42 | _i2cRAddr = MS5611_ADDR_R; |
loopsva | 9:6104e8cdb3ec | 43 | MStype = CSBpin; |
loopsva | 9:6104e8cdb3ec | 44 | if((CSBpin == CSBpin_1) || (CSBpin == MS5805)) { |
loopsva | 7:90ee2168baa7 | 45 | _i2cWAddr -= 2; |
loopsva | 7:90ee2168baa7 | 46 | _i2cRAddr -= 2; |
loopsva | 7:90ee2168baa7 | 47 | |
loopsva | 7:90ee2168baa7 | 48 | } |
loopsva | 0:f97f410d4a21 | 49 | } |
loopsva | 0:f97f410d4a21 | 50 | |
loopsva | 0:f97f410d4a21 | 51 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 52 | //! @brief send I2C start condition and the address byte |
loopsva | 0:f97f410d4a21 | 53 | //! |
loopsva | 0:f97f410d4a21 | 54 | //! @return 0 |
loopsva | 0:f97f410d4a21 | 55 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 56 | |
loopsva | 0:f97f410d4a21 | 57 | int ms5611::m_i2c_start(bool readMode) { |
loopsva | 0:f97f410d4a21 | 58 | int twst; |
loopsva | 0:f97f410d4a21 | 59 | _i2c.start(); |
loopsva | 0:f97f410d4a21 | 60 | if(readMode == true) { |
loopsva | 7:90ee2168baa7 | 61 | twst = m_i2c_write(_i2cRAddr); |
loopsva | 0:f97f410d4a21 | 62 | } else { |
loopsva | 7:90ee2168baa7 | 63 | twst = m_i2c_write(_i2cWAddr); |
loopsva | 0:f97f410d4a21 | 64 | } |
loopsva | 0:f97f410d4a21 | 65 | return(twst); |
loopsva | 0:f97f410d4a21 | 66 | } |
loopsva | 0:f97f410d4a21 | 67 | |
loopsva | 0:f97f410d4a21 | 68 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 69 | //! @brief send I2C stop condition |
loopsva | 0:f97f410d4a21 | 70 | //! |
loopsva | 0:f97f410d4a21 | 71 | //! @return none |
loopsva | 0:f97f410d4a21 | 72 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 73 | |
loopsva | 0:f97f410d4a21 | 74 | void ms5611::m_i2c_stop(void) { |
loopsva | 0:f97f410d4a21 | 75 | _i2c.stop(); |
loopsva | 0:f97f410d4a21 | 76 | } |
loopsva | 0:f97f410d4a21 | 77 | |
loopsva | 0:f97f410d4a21 | 78 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 79 | //! @brief send I2C stop condition |
loopsva | 0:f97f410d4a21 | 80 | //! |
loopsva | 0:f97f410d4a21 | 81 | //! @return remote ack status |
loopsva | 0:f97f410d4a21 | 82 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 83 | |
loopsva | 0:f97f410d4a21 | 84 | unsigned char ms5611::m_i2c_write(unsigned char data) { |
loopsva | 0:f97f410d4a21 | 85 | int twst = _i2c.write(data); |
loopsva | 0:f97f410d4a21 | 86 | return(twst); |
loopsva | 0:f97f410d4a21 | 87 | } |
loopsva | 0:f97f410d4a21 | 88 | |
loopsva | 0:f97f410d4a21 | 89 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 90 | //! @brief read I2C byte with acknowledgment |
loopsva | 0:f97f410d4a21 | 91 | //! |
loopsva | 0:f97f410d4a21 | 92 | //! @return read byte |
loopsva | 0:f97f410d4a21 | 93 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 94 | |
loopsva | 0:f97f410d4a21 | 95 | unsigned char ms5611::m_i2c_readAck(void) { |
loopsva | 0:f97f410d4a21 | 96 | int twst = _i2c.read(1); |
loopsva | 0:f97f410d4a21 | 97 | return(twst); |
loopsva | 0:f97f410d4a21 | 98 | } |
loopsva | 0:f97f410d4a21 | 99 | |
loopsva | 0:f97f410d4a21 | 100 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 101 | //! @brief read I2C byte without acknowledgment |
loopsva | 0:f97f410d4a21 | 102 | //! |
loopsva | 0:f97f410d4a21 | 103 | //! @return read byte |
loopsva | 0:f97f410d4a21 | 104 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 105 | |
loopsva | 0:f97f410d4a21 | 106 | unsigned char ms5611::m_i2c_readNak(void) { |
loopsva | 0:f97f410d4a21 | 107 | int twst = _i2c.read(0); |
loopsva | 0:f97f410d4a21 | 108 | return(twst); |
loopsva | 0:f97f410d4a21 | 109 | } |
loopsva | 0:f97f410d4a21 | 110 | |
loopsva | 0:f97f410d4a21 | 111 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 112 | //! @brief send command using I2C hardware interface |
loopsva | 0:f97f410d4a21 | 113 | //! |
loopsva | 0:f97f410d4a21 | 114 | //! @return none |
loopsva | 0:f97f410d4a21 | 115 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 116 | |
loopsva | 9:6104e8cdb3ec | 117 | int ms5611::m_i2c_send(char cmd) { |
loopsva | 0:f97f410d4a21 | 118 | unsigned char ret; |
loopsva | 2:05804ed70748 | 119 | ret = m_i2c_start(false); |
loopsva | 2:05804ed70748 | 120 | if(!(ret)) { |
loopsva | 0:f97f410d4a21 | 121 | m_i2c_stop(); |
loopsva | 2:05804ed70748 | 122 | } else { |
loopsva | 0:f97f410d4a21 | 123 | ret = m_i2c_write(cmd); |
loopsva | 0:f97f410d4a21 | 124 | m_i2c_stop(); |
loopsva | 0:f97f410d4a21 | 125 | } |
loopsva | 9:6104e8cdb3ec | 126 | return(ret); |
loopsva | 0:f97f410d4a21 | 127 | } |
loopsva | 0:f97f410d4a21 | 128 | |
loopsva | 0:f97f410d4a21 | 129 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 130 | //! @brief send reset sequence |
loopsva | 0:f97f410d4a21 | 131 | //! |
loopsva | 0:f97f410d4a21 | 132 | //! @return none |
loopsva | 0:f97f410d4a21 | 133 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 134 | |
loopsva | 9:6104e8cdb3ec | 135 | int ms5611::cmd_reset() { |
loopsva | 8:461f68bc94f2 | 136 | #if defined MS5611i2cLOWLEVEL |
loopsva | 9:6104e8cdb3ec | 137 | int ret = m_i2c_send(MS5611_CMD_RESET); |
loopsva | 9:6104e8cdb3ec | 138 | if(!(ret)) return(ret); |
loopsva | 8:461f68bc94f2 | 139 | #else |
loopsva | 8:461f68bc94f2 | 140 | char cobuf[1]; |
loopsva | 8:461f68bc94f2 | 141 | cobuf[0] = MS5611_CMD_RESET; |
loopsva | 9:6104e8cdb3ec | 142 | int ret = _i2c.write(_i2cWAddr, cobuf, 1, false); |
loopsva | 9:6104e8cdb3ec | 143 | if((ret)) return(0); |
loopsva | 8:461f68bc94f2 | 144 | #endif |
loopsva | 9:6104e8cdb3ec | 145 | |
loopsva | 9:6104e8cdb3ec | 146 | #ifdef RTOS_H |
loopsva | 9:6104e8cdb3ec | 147 | Thread::wait(4); |
loopsva | 9:6104e8cdb3ec | 148 | #else |
loopsva | 2:05804ed70748 | 149 | wait_ms(4); |
loopsva | 9:6104e8cdb3ec | 150 | #endif |
loopsva | 9:6104e8cdb3ec | 151 | |
loopsva | 0:f97f410d4a21 | 152 | loadCoefs(); |
loopsva | 9:6104e8cdb3ec | 153 | #if defined MS5611i2cLOWLEVEL |
loopsva | 9:6104e8cdb3ec | 154 | return(ret); |
loopsva | 9:6104e8cdb3ec | 155 | #else |
loopsva | 9:6104e8cdb3ec | 156 | return(1); |
loopsva | 9:6104e8cdb3ec | 157 | #endif |
loopsva | 0:f97f410d4a21 | 158 | } |
loopsva | 0:f97f410d4a21 | 159 | |
loopsva | 0:f97f410d4a21 | 160 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 161 | //! @brief preform adc conversion |
loopsva | 0:f97f410d4a21 | 162 | //! |
loopsva | 0:f97f410d4a21 | 163 | //! @return 24bit result |
loopsva | 0:f97f410d4a21 | 164 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 165 | |
loopsva | 0:f97f410d4a21 | 166 | unsigned long ms5611::cmd_adc(char cmd) { |
loopsva | 9:6104e8cdb3ec | 167 | char cobuf[3] = {0, 0, 0}; |
loopsva | 0:f97f410d4a21 | 168 | unsigned long temp = 0; |
loopsva | 8:461f68bc94f2 | 169 | #if defined MS5611i2cLOWLEVEL |
loopsva | 9:6104e8cdb3ec | 170 | m_i2c_start(false); |
loopsva | 9:6104e8cdb3ec | 171 | m_i2c_write(MS5611_CMD_ADC_CONV + cmd); |
loopsva | 9:6104e8cdb3ec | 172 | m_i2c_stop(); |
loopsva | 8:461f68bc94f2 | 173 | #else |
loopsva | 8:461f68bc94f2 | 174 | cobuf[0] = MS5611_CMD_ADC_CONV + cmd; |
loopsva | 8:461f68bc94f2 | 175 | _i2c.write(_i2cWAddr, cobuf, 1, false); |
loopsva | 8:461f68bc94f2 | 176 | #endif |
loopsva | 2:05804ed70748 | 177 | switch (cmd & 0x0f) { |
loopsva | 9:6104e8cdb3ec | 178 | #ifdef RTOS_H |
loopsva | 9:6104e8cdb3ec | 179 | case MS5611_CMD_ADC_256 : Thread::wait(1); break; |
loopsva | 9:6104e8cdb3ec | 180 | case MS5611_CMD_ADC_512 : Thread::wait(3); break; |
loopsva | 9:6104e8cdb3ec | 181 | case MS5611_CMD_ADC_1024: Thread::wait(4); break; |
loopsva | 9:6104e8cdb3ec | 182 | case MS5611_CMD_ADC_2048: Thread::wait(6); break; |
loopsva | 9:6104e8cdb3ec | 183 | case MS5611_CMD_ADC_4096: Thread::wait(10); break; |
loopsva | 9:6104e8cdb3ec | 184 | case MS5805_CMD_ADC_8192: Thread::wait(19); break; |
loopsva | 9:6104e8cdb3ec | 185 | #else |
loopsva | 0:f97f410d4a21 | 186 | case MS5611_CMD_ADC_256 : wait_us(900); break; |
loopsva | 0:f97f410d4a21 | 187 | case MS5611_CMD_ADC_512 : wait_ms(3); break; |
loopsva | 0:f97f410d4a21 | 188 | case MS5611_CMD_ADC_1024: wait_ms(4); break; |
loopsva | 0:f97f410d4a21 | 189 | case MS5611_CMD_ADC_2048: wait_ms(6); break; |
loopsva | 0:f97f410d4a21 | 190 | case MS5611_CMD_ADC_4096: wait_ms(10); break; |
loopsva | 9:6104e8cdb3ec | 191 | case MS5805_CMD_ADC_8192: wait_ms(19); break; |
loopsva | 9:6104e8cdb3ec | 192 | #endif |
loopsva | 0:f97f410d4a21 | 193 | } |
loopsva | 8:461f68bc94f2 | 194 | #if defined MS5611i2cLOWLEVEL |
loopsva | 9:6104e8cdb3ec | 195 | m_i2c_start(false); |
loopsva | 9:6104e8cdb3ec | 196 | m_i2c_write(MS5611_CMD_ADC_READ); |
loopsva | 9:6104e8cdb3ec | 197 | m_i2c_start(true); |
loopsva | 9:6104e8cdb3ec | 198 | cobuf[0] = m_i2c_readAck(); |
loopsva | 9:6104e8cdb3ec | 199 | cobuf[1] = m_i2c_readAck(); |
loopsva | 9:6104e8cdb3ec | 200 | cobuf[2] = m_i2c_readNak(); |
loopsva | 9:6104e8cdb3ec | 201 | m_i2c_stop(); |
loopsva | 8:461f68bc94f2 | 202 | #else |
loopsva | 8:461f68bc94f2 | 203 | cobuf[0] = MS5611_CMD_ADC_READ; |
loopsva | 8:461f68bc94f2 | 204 | _i2c.write(_i2cWAddr, cobuf, 1, true); |
loopsva | 8:461f68bc94f2 | 205 | cobuf[0] = 0; |
loopsva | 9:6104e8cdb3ec | 206 | _i2c.read(_i2cRAddr, cobuf, 3, false); |
loopsva | 8:461f68bc94f2 | 207 | #endif |
loopsva | 8:461f68bc94f2 | 208 | //if(ret) printf("\n*** ms5611 ADC Read Error "); |
loopsva | 0:f97f410d4a21 | 209 | temp = (cobuf[0] << 16) + (cobuf[1] << 8) + cobuf[2]; |
loopsva | 0:f97f410d4a21 | 210 | return temp; |
loopsva | 0:f97f410d4a21 | 211 | } |
loopsva | 0:f97f410d4a21 | 212 | |
loopsva | 0:f97f410d4a21 | 213 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 214 | //! @brief Read calibration coefficients |
loopsva | 0:f97f410d4a21 | 215 | //! |
loopsva | 0:f97f410d4a21 | 216 | //! @return coefficient |
loopsva | 0:f97f410d4a21 | 217 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 218 | |
loopsva | 0:f97f410d4a21 | 219 | unsigned int ms5611::cmd_prom(char coef_num) { |
loopsva | 9:6104e8cdb3ec | 220 | char cobuf[2] = {0, 0}; |
loopsva | 0:f97f410d4a21 | 221 | unsigned int rC = 0; |
loopsva | 8:461f68bc94f2 | 222 | #if defined MS5611i2cLOWLEVEL |
loopsva | 9:6104e8cdb3ec | 223 | m_i2c_start(false); |
loopsva | 9:6104e8cdb3ec | 224 | m_i2c_write(MS5611_CMD_PROM_RD + coef_num * 2);// send PROM READ command |
loopsva | 9:6104e8cdb3ec | 225 | m_i2c_start(true); |
loopsva | 9:6104e8cdb3ec | 226 | cobuf[0] = m_i2c_readAck(); |
loopsva | 9:6104e8cdb3ec | 227 | cobuf[1] = m_i2c_readNak(); |
loopsva | 9:6104e8cdb3ec | 228 | m_i2c_stop(); |
loopsva | 8:461f68bc94f2 | 229 | #else |
loopsva | 8:461f68bc94f2 | 230 | cobuf[0] = MS5611_CMD_PROM_RD + coef_num * 2; |
loopsva | 8:461f68bc94f2 | 231 | _i2c.write(_i2cWAddr, cobuf, 1, true); |
loopsva | 8:461f68bc94f2 | 232 | cobuf[0] = 0; |
loopsva | 9:6104e8cdb3ec | 233 | _i2c.read(_i2cRAddr, cobuf, 2, false); |
loopsva | 8:461f68bc94f2 | 234 | #endif |
loopsva | 8:461f68bc94f2 | 235 | //if(ret) printf("\n*** ms5611 PROM Read Error "); |
loopsva | 0:f97f410d4a21 | 236 | rC = cobuf[0] * 256 + cobuf[1]; |
loopsva | 0:f97f410d4a21 | 237 | return rC; |
loopsva | 0:f97f410d4a21 | 238 | } |
loopsva | 0:f97f410d4a21 | 239 | |
loopsva | 0:f97f410d4a21 | 240 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 241 | //! @brief calculate the CRC code |
loopsva | 0:f97f410d4a21 | 242 | //! |
loopsva | 0:f97f410d4a21 | 243 | //! @return crc code |
loopsva | 0:f97f410d4a21 | 244 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 245 | |
loopsva | 0:f97f410d4a21 | 246 | unsigned char ms5611::crc4(unsigned int n_prom[]) { |
loopsva | 9:6104e8cdb3ec | 247 | unsigned int n_rem = 0; |
loopsva | 9:6104e8cdb3ec | 248 | unsigned int crc_read = 0; |
loopsva | 9:6104e8cdb3ec | 249 | unsigned char n_bit = 0; |
loopsva | 9:6104e8cdb3ec | 250 | if(MStype == ms5611::MS5805) { |
loopsva | 9:6104e8cdb3ec | 251 | n_prom[0] = (n_prom[0] & 0x0FFF); |
loopsva | 9:6104e8cdb3ec | 252 | n_prom[7] = 0; |
loopsva | 9:6104e8cdb3ec | 253 | } else { |
loopsva | 9:6104e8cdb3ec | 254 | crc_read = n_prom[7]; |
loopsva | 9:6104e8cdb3ec | 255 | n_prom[7]=(0xFF00 & (n_prom[7])); |
loopsva | 9:6104e8cdb3ec | 256 | } |
loopsva | 2:05804ed70748 | 257 | for (int cnt = 0; cnt < 16; cnt++) { |
loopsva | 0:f97f410d4a21 | 258 | if (cnt%2 == 1) { |
loopsva | 0:f97f410d4a21 | 259 | n_rem ^= (unsigned short) ((n_prom[cnt>>1]) & 0x00FF); |
loopsva | 0:f97f410d4a21 | 260 | } else { |
loopsva | 0:f97f410d4a21 | 261 | n_rem ^= (unsigned short) (n_prom[cnt>>1]>>8); |
loopsva | 0:f97f410d4a21 | 262 | } |
loopsva | 0:f97f410d4a21 | 263 | for (n_bit = 8; n_bit > 0; n_bit--) { |
loopsva | 0:f97f410d4a21 | 264 | if (n_rem & (0x8000)) { |
loopsva | 0:f97f410d4a21 | 265 | n_rem = (n_rem << 1) ^ 0x3000; |
loopsva | 0:f97f410d4a21 | 266 | } else { |
loopsva | 0:f97f410d4a21 | 267 | n_rem = (n_rem << 1); |
loopsva | 0:f97f410d4a21 | 268 | } |
loopsva | 0:f97f410d4a21 | 269 | } |
loopsva | 0:f97f410d4a21 | 270 | } |
loopsva | 9:6104e8cdb3ec | 271 | n_rem= ((n_rem >> 12) & 0x000F); |
loopsva | 9:6104e8cdb3ec | 272 | if(!(MStype == ms5611::MS5805)) { |
loopsva | 9:6104e8cdb3ec | 273 | n_prom[7]=crc_read; |
loopsva | 9:6104e8cdb3ec | 274 | } |
loopsva | 0:f97f410d4a21 | 275 | return (n_rem ^ 0x0); |
loopsva | 2:05804ed70748 | 276 | } |
loopsva | 2:05804ed70748 | 277 | |
loopsva | 0:f97f410d4a21 | 278 | /* |
loopsva | 0:f97f410d4a21 | 279 | 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 | 280 | Coefficient table below). It is thus important to clear those bytes from the calculation buffer before proceeding |
loopsva | 0:f97f410d4a21 | 281 | with the CRC calculation itself: |
loopsva | 0:f97f410d4a21 | 282 | n_prom[7]=(0xFF00 & (n_prom[7])); //CRC byte is replaced by 0 |
loopsva | 0:f97f410d4a21 | 283 | As a simple test of the CRC code, the following coefficient table could be used: |
loopsva | 0:f97f410d4a21 | 284 | unsigned int nprom[] = {0x3132,0x3334,0x3536,0x3738,0x3940,0x4142,0x4344,0x4500}; |
loopsva | 0:f97f410d4a21 | 285 | the resulting calculated CRC should be 0xB. |
loopsva | 0:f97f410d4a21 | 286 | |
loopsva | 0:f97f410d4a21 | 287 | DB 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 |
loopsva | 0:f97f410d4a21 | 288 | Addr |
loopsva | 0:f97f410d4a21 | 289 | 0 16 bit reserved for manufacturer |
loopsva | 0:f97f410d4a21 | 290 | 1 Coefficient 1 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 291 | 2 Coefficient 2 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 292 | 3 Coefficient 3 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 293 | 4 Coefficient 4 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 294 | 5 Coefficient 5 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 295 | 6 Coefficient 6 (16 bit unsigned) |
loopsva | 0:f97f410d4a21 | 296 | 7 0 0 0 0 CRC(0x0) |
loopsva | 0:f97f410d4a21 | 297 | */ |
loopsva | 0:f97f410d4a21 | 298 | /* |
loopsva | 0:f97f410d4a21 | 299 | //Returns 0x0b as per AP520_004 |
loopsva | 2:05804ed70748 | 300 | C[0] = 0x3132; |
loopsva | 2:05804ed70748 | 301 | C[1] = 0x3334; |
loopsva | 2:05804ed70748 | 302 | C[2] = 0x3536; |
loopsva | 2:05804ed70748 | 303 | C[3] = 0x3738; |
loopsva | 2:05804ed70748 | 304 | C[4] = 0x3940; |
loopsva | 2:05804ed70748 | 305 | C[5] = 0x4142; |
loopsva | 2:05804ed70748 | 306 | C[6] = 0x4344; |
loopsva | 2:05804ed70748 | 307 | C[7] = 0x4546; |
loopsva | 0:f97f410d4a21 | 308 | n_crc = ms.crc4(C); // calculate the CRC |
loopsva | 0:f97f410d4a21 | 309 | pc.printf("testing CRC: 0x%x\n", n_crc); |
loopsva | 0:f97f410d4a21 | 310 | */ |
loopsva | 2:05804ed70748 | 311 | |
loopsva | 0:f97f410d4a21 | 312 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 313 | //! @brief load all calibration coefficients |
loopsva | 0:f97f410d4a21 | 314 | //! |
loopsva | 0:f97f410d4a21 | 315 | //! @return none |
loopsva | 0:f97f410d4a21 | 316 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 317 | |
loopsva | 0:f97f410d4a21 | 318 | void ms5611::loadCoefs() { |
loopsva | 8:461f68bc94f2 | 319 | //printf(" - ms5611 coeffs\r\n"); |
loopsva | 0:f97f410d4a21 | 320 | for (int i = 0; i < 8; i++){ |
loopsva | 0:f97f410d4a21 | 321 | wait_ms(50); |
loopsva | 2:05804ed70748 | 322 | C[i] = cmd_prom(i); |
loopsva | 8:461f68bc94f2 | 323 | //printf(" - C[%d] = 0x%04x\r\n", i, C[i]); |
loopsva | 0:f97f410d4a21 | 324 | } |
loopsva | 2:05804ed70748 | 325 | unsigned char n_crc = crc4(C); |
loopsva | 8:461f68bc94f2 | 326 | //printf(" - crc = 0x%02x\r\n", n_crc); |
loopsva | 0:f97f410d4a21 | 327 | } |
loopsva | 0:f97f410d4a21 | 328 | |
loopsva | 0:f97f410d4a21 | 329 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 330 | //! @brief calculate temperature and pressure |
loopsva | 0:f97f410d4a21 | 331 | //! |
loopsva | 0:f97f410d4a21 | 332 | //! @return none |
loopsva | 0:f97f410d4a21 | 333 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 334 | |
loopsva | 0:f97f410d4a21 | 335 | void ms5611::calcPT() { |
loopsva | 9:6104e8cdb3ec | 336 | int32_t D1 = 0; |
loopsva | 9:6104e8cdb3ec | 337 | int32_t D2 = 0; |
loopsva | 9:6104e8cdb3ec | 338 | if(MStype == ms5611::MS5805) { |
loopsva | 9:6104e8cdb3ec | 339 | D2 = cmd_adc(MS5611_CMD_ADC_D2 + MS5805_CMD_ADC_8192); // read D2 |
loopsva | 9:6104e8cdb3ec | 340 | D1 = cmd_adc(MS5611_CMD_ADC_D1 + MS5805_CMD_ADC_8192); // read D1 |
loopsva | 9:6104e8cdb3ec | 341 | } else { |
loopsva | 9:6104e8cdb3ec | 342 | D2 = cmd_adc(MS5611_CMD_ADC_D2 + MS5611_CMD_ADC_4096); // read D2 |
loopsva | 9:6104e8cdb3ec | 343 | D1 = cmd_adc(MS5611_CMD_ADC_D1 + MS5611_CMD_ADC_4096); // read D1 |
loopsva | 9:6104e8cdb3ec | 344 | } |
loopsva | 9:6104e8cdb3ec | 345 | |
loopsva | 3:c2d1b0d432ad | 346 | int64_t dT = D2 - ((uint64_t)C[5] << 8); |
loopsva | 2:05804ed70748 | 347 | int64_t OFF = ((uint32_t)C[2] << 16) + ((dT * (C[4]) >> 7)); //was OFF = (C[2] << 17) + dT * C[4] / (1 << 6); |
loopsva | 2:05804ed70748 | 348 | int64_t SENS = ((uint32_t)C[1] << 15) + ((dT * (C[3]) >> 8)); //was SENS = (C[1] << 16) + dT * C[3] / (1 << 7); |
loopsva | 2:05804ed70748 | 349 | T = (2000 + (((uint64_t)dT * C[6]) / (float)(1 << 23))) / 100; |
loopsva | 2:05804ed70748 | 350 | int32_t TEMP = 2000 + (int64_t)dT * (int64_t)C[6] / (int64_t)(1 << 23); |
loopsva | 0:f97f410d4a21 | 351 | |
loopsva | 2:05804ed70748 | 352 | if(TEMP < 2000) { // if temperature lower than 20 Celsius |
loopsva | 9:6104e8cdb3ec | 353 | float T1 = 0.0; |
loopsva | 9:6104e8cdb3ec | 354 | int64_t OFF1, SENS1 = 0; |
loopsva | 9:6104e8cdb3ec | 355 | if(MStype == ms5611::MS5805) { |
loopsva | 9:6104e8cdb3ec | 356 | T1 = 11 * ((dT * dT) >> 35); |
loopsva | 9:6104e8cdb3ec | 357 | OFF1 = 31 * ((TEMP - 2000) * (TEMP - 2000)) >> 3; |
loopsva | 9:6104e8cdb3ec | 358 | SENS1 = 63 * ((TEMP - 2000) * (TEMP - 2000)) >> 5; |
loopsva | 9:6104e8cdb3ec | 359 | } else { |
loopsva | 9:6104e8cdb3ec | 360 | T1 = (TEMP - 2000) * (TEMP - 2000); |
loopsva | 9:6104e8cdb3ec | 361 | OFF1 = (5 * T1) / 2; |
loopsva | 9:6104e8cdb3ec | 362 | SENS1 = (5 * T1) / 4; |
loopsva | 9:6104e8cdb3ec | 363 | |
loopsva | 9:6104e8cdb3ec | 364 | if(TEMP < -1500) { // if temperature lower than -15 Celsius |
loopsva | 9:6104e8cdb3ec | 365 | T1 = (TEMP + 1500) * (TEMP + 1500); |
loopsva | 9:6104e8cdb3ec | 366 | OFF1 += 7 * T1; |
loopsva | 9:6104e8cdb3ec | 367 | SENS1 += 11 * T1 / 2; |
loopsva | 9:6104e8cdb3ec | 368 | } |
loopsva | 9:6104e8cdb3ec | 369 | } |
loopsva | 2:05804ed70748 | 370 | OFF -= OFF1; |
loopsva | 2:05804ed70748 | 371 | SENS -= SENS1; |
loopsva | 9:6104e8cdb3ec | 372 | T = ((double)TEMP - T1)/ 100.0; |
loopsva | 2:05804ed70748 | 373 | } |
loopsva | 2:05804ed70748 | 374 | // int64_t P1 = ((((int64_t)D1 * SENS) >> 21) - OFF) >> 15; |
loopsva | 2:05804ed70748 | 375 | P = ((((int64_t)D1 * SENS ) >> 21) - OFF) / (double) (1 << 15) / 100.0; |
loopsva | 0:f97f410d4a21 | 376 | } |
loopsva | 0:f97f410d4a21 | 377 | |
loopsva | 0:f97f410d4a21 | 378 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 379 | //! @brief calculate temperature |
loopsva | 0:f97f410d4a21 | 380 | //! |
loopsva | 0:f97f410d4a21 | 381 | //! @return double temperature degC |
loopsva | 0:f97f410d4a21 | 382 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 383 | |
loopsva | 0:f97f410d4a21 | 384 | double ms5611::calcTemp() { |
loopsva | 0:f97f410d4a21 | 385 | calcPT(); |
loopsva | 0:f97f410d4a21 | 386 | return(T); |
loopsva | 0:f97f410d4a21 | 387 | } |
loopsva | 0:f97f410d4a21 | 388 | |
loopsva | 0:f97f410d4a21 | 389 | //******************************************************** |
loopsva | 3:c2d1b0d432ad | 390 | //! @brief calculate pressure |
loopsva | 0:f97f410d4a21 | 391 | //! |
loopsva | 0:f97f410d4a21 | 392 | //! @return double barometric pressure millibar |
loopsva | 0:f97f410d4a21 | 393 | //******************************************************** |
loopsva | 0:f97f410d4a21 | 394 | |
loopsva | 0:f97f410d4a21 | 395 | double ms5611::calcPressure() { |
loopsva | 0:f97f410d4a21 | 396 | calcPT(); |
loopsva | 0:f97f410d4a21 | 397 | return(P); |
loopsva | 2:05804ed70748 | 398 | } |
loopsva | 3:c2d1b0d432ad | 399 | |
loopsva | 3:c2d1b0d432ad | 400 | //******************************************************** |
loopsva | 3:c2d1b0d432ad | 401 | //! @brief get pressure, no calculation |
loopsva | 3:c2d1b0d432ad | 402 | //! |
loopsva | 3:c2d1b0d432ad | 403 | //! @return double barometric pressure millibar |
loopsva | 3:c2d1b0d432ad | 404 | //******************************************************** |
loopsva | 3:c2d1b0d432ad | 405 | |
loopsva | 3:c2d1b0d432ad | 406 | double ms5611::getPressure() { |
loopsva | 3:c2d1b0d432ad | 407 | calcPT(); |
loopsva | 3:c2d1b0d432ad | 408 | return(P); |
loopsva | 3:c2d1b0d432ad | 409 | } |
loopsva | 3:c2d1b0d432ad | 410 | |
loopsva | 3:c2d1b0d432ad | 411 | //******************************************************** |
loopsva | 5:0d7b229474c6 | 412 | //! @brief get altitude from known sea level barometer, |
loopsva | 5:0d7b229474c6 | 413 | //! @ no pre-pressure calculation |
loopsva | 3:c2d1b0d432ad | 414 | //! |
loopsva | 3:c2d1b0d432ad | 415 | //! @enter float sea level barometer |
loopsva | 3:c2d1b0d432ad | 416 | //! @return float altitude in feet |
loopsva | 3:c2d1b0d432ad | 417 | //******************************************************** |
loopsva | 3:c2d1b0d432ad | 418 | |
loopsva | 3:c2d1b0d432ad | 419 | float ms5611::getAltitudeFT(float sea_pressure) { |
loopsva | 3:c2d1b0d432ad | 420 | A = (1 - (pow((P / (double)sea_pressure), 0.190284))) * 145366.45; |
loopsva | 3:c2d1b0d432ad | 421 | return((float)A); |
loopsva | 3:c2d1b0d432ad | 422 | } |
loopsva | 5:0d7b229474c6 | 423 | |
loopsva | 5:0d7b229474c6 | 424 | //******************************************************** |
loopsva | 5:0d7b229474c6 | 425 | //! @brief get sea level pressure from known altitude(ft), |
loopsva | 5:0d7b229474c6 | 426 | //! @ no pre-pressure calculation |
loopsva | 5:0d7b229474c6 | 427 | //! |
loopsva | 5:0d7b229474c6 | 428 | //! @enter float known altitude in feet |
loopsva | 5:0d7b229474c6 | 429 | //! @return float seal level barometer in mb |
loopsva | 5:0d7b229474c6 | 430 | //******************************************************** |
loopsva | 5:0d7b229474c6 | 431 | |
loopsva | 5:0d7b229474c6 | 432 | float ms5611::getSeaLevelBaroFT(float known_alt) { |
loopsva | 9:6104e8cdb3ec | 433 | S = pow(pow((P * MB_INHG_DOUBLE), 0.190284) + 0.00001313 * known_alt , 5.2553026) * INHG_MB_DOUBLE; |
loopsva | 5:0d7b229474c6 | 434 | return((float)S); |
loopsva | 5:0d7b229474c6 | 435 | } |
loopsva | 5:0d7b229474c6 | 436 | |
loopsva | 5:0d7b229474c6 | 437 | //******************************************************** |
loopsva | 5:0d7b229474c6 | 438 | //! @brief get sea level pressure from known altitude(m), |
loopsva | 5:0d7b229474c6 | 439 | //! @ no pre-pressure calculation |
loopsva | 5:0d7b229474c6 | 440 | //! |
loopsva | 5:0d7b229474c6 | 441 | //! @enter float known altitude in meters |
loopsva | 5:0d7b229474c6 | 442 | //! @return float seal level barometer in mb |
loopsva | 5:0d7b229474c6 | 443 | //******************************************************** |
loopsva | 5:0d7b229474c6 | 444 | |
loopsva | 5:0d7b229474c6 | 445 | float ms5611::getSeaLevelBaroM(float known_alt) { |
loopsva | 9:6104e8cdb3ec | 446 | S = pow(pow((P * MB_INHG_DOUBLE), 0.190284) + 0.00001313 * known_alt * FEET_METERS , 5.2553026) * INHG_MB_DOUBLE; |
loopsva | 5:0d7b229474c6 | 447 | return((float)S); |
loopsva | 5:0d7b229474c6 | 448 | } |
loopsva | 9:6104e8cdb3ec | 449 |