Diff: MS5803_14BA.cpp

Revision:

0:a5f77652b3bb

Child:

1:373f735e50e2

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MS5803_14BA.cpp	Fri Apr 24 18:56:03 2015 +0000
@@ -0,0 +1,114 @@
+/*
+    Permission is hereby granted, free of charge, to any person obtaining a copy
+    of this software and associated documentation files (the "Software"), to deal
+    in the Software without restriction, including without limitation the rights
+    to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+    copies of the Software, and to permit persons to whom the Software is
+    furnished to do so, subject to the following conditions:
+
+    The above copyright notice and this permission notice shall be included in
+    all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+    THE SOFTWARE.
+
+  * Demo Program
+  * Barometer Sensor (Altimeter) MS5803-01BA of MEAS Switzerland     (www.meas-spec.com).
+  * The driver uses I2C mode (sensor PS pin low).
+  * Other types of MEAS are compatible but not tested.
+  * Written by Raig Kaufer distribute freely!
+  *
+  * Modified for MS5803-14BA by Francesco Adamo, Italy
+ */
+
+#include <stdlib.h>
+#include "MS5803_14BA.h"
+
+MS5803_14BA::MS5803_14BA(PinName sda, PinName scl, char MS5803_ADDR) : _i2c(sda, scl) {
+    device_address = MS5803_ADDR << 1;
+    _d1_osr = D1_OSR_4096;
+    _d2_osr = D2_OSR_4096;
+    reset();    // reset the sensor
+    readPROM(); // read the calibration values
+}
+
+MS5803_14BA::MS5803_14BA(PinName sda, PinName scl, char MS5803_ADDR, char d1_osr, char d2_osr) : _i2c( sda, scl ) {
+    device_address = MS5803_ADDR << 1;
+    _d1_osr = D1_OSR_4096;
+    _d2_osr = D2_OSR_4096;
+    reset();    // reset the sensor
+    readPROM(); // read the calibration values and store them in array C[ ] 
+}
+
+/* Send soft reset to the sensor */
+void MS5803_14BA::reset(void) {
+    MS5803_tx_data[0] = COMMAND_RESET;
+    _i2c.write(device_address,  MS5803_tx_data, 1);
+    wait_ms(20);
+}
+
+/* read the sensor calibration data from ROM */
+void MS5803_14BA::readPROM(void) {
+    for (uint8_t i = 0; i < 8; i++) {
+        MS5803_tx_data[0] = COMMAND_READ_PROM + (i << 1);
+        _i2c.write( device_address,  MS5803_tx_data, 1);
+        _i2c.read( device_address,  MS5803_rx_data, 2);
+        C[i] = (MS5803_rx_data[0] << 8) + MS5803_rx_data[1];
+    }
+}
+
+/* Start the sensor pressure conversion */
+void MS5803_14BA::convertD1(void) {
+    MS5803_tx_data[0] = _d1_osr;
+    _i2c.write( device_address,  MS5803_tx_data, 1);
+}
+
+/* Start the sensor temperature conversion */
+void MS5803_14BA::convertD2(void) {
+    MS5803_tx_data[0] = _d2_osr;
+    _i2c.write(device_address,  MS5803_tx_data, 1);
+}
+
+/* Read the previous started conversion results */
+int32_t MS5803_14BA::readADC(void) {
+    wait_ms(150);
+    MS5803_tx_data[0] = COMMAND_READ_ADC;
+    _i2c.write(device_address,  MS5803_tx_data, 1);
+    _i2c.read(device_address,  MS5803_rx_data, 3);
+    return (MS5803_rx_data[0] << 16) + (MS5803_rx_data[1] << 8) + MS5803_rx_data[2];
+}
+
+/* return the results */
+float MS5803_14BA::getPressure(void) {
+    return P_MS5803;
+}
+
+float MS5803_14BA::getTemperature (void) {
+    return T_MS5803;
+}
+
+/* Sensor reading and calculation procedure */
+void MS5803_14BA::convert(void) {
+    int32_t dT, TEMP;
+    int64_t OFF, SENS, P;
+
+    convertD1();    // start pressure convertion
+    D1 = readADC(); // read the pressure value
+    convertD2();    // start temperature convertion
+    D2 = readADC(); // read the temperature value
+
+    /* calculation according MS5803-14BA data sheet */
+    dT       = D2 - (C[5]* 256);
+    TEMP     = 2000 + (dT * C[6])/8388608;
+    T_MS5803 = (float) TEMP/100.0f; // result of temperature in deg C in this var
+
+    OFF      = (int64_t)65536*C[2] + ((int64_t)dT * (int64_t)C[4])/128;
+    SENS     = (int64_t)32768*C[1] + ((int64_t)dT * (int64_t)C[3])/256;
+    P    = (((int64_t)D1 * SENS)/2097152 - OFF)/32768;
+    P_MS5803 = (float) P/10.0f; // result of pressure in mBar in this var
+}