Hilton Tnunay
sdfghj
Diff: MS5611.h
- Revision:
- 0:c8bcb12163ab
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/MS5611.h Thu Apr 24 12:57:00 2014 +0000
@@ -0,0 +1,171 @@
+#ifndef MS5611_H
+#define MS5611_H
+
+#include "mbed.h"
+
+
+#define SEA_PRESS 1013.25 //default sea level pressure level in mb
+#define KNOWNALT 327.0 //default known altitude, 5200 Franklin Dr., 94588
+#define INHG 0.02952998751 //convert mb to in/Hg constant
+#define MB 33.8638815 //convert in/Hg to mb constant
+#define FTMETERS 0.3048 //convert feet to meters
+
+
+/** Software routines to access the Measurement Specialties' MS5611-01BA03
+ * Variometer Module using the I2C bus option. The MS5611 is a 24 bit
+ * temperature and pressure transducer for high accuracy Barometer and
+ * Altimeter applications. It also includes compensation coefficients
+ * stored within the device.
+ *
+ * Code adapted from Measurement Specialties:
+ * "AN520 C-code example for MS56xx, MS57xx (except analog sensor), and
+ * MS58xx series pressure sensors"
+ *
+ * Note: AN520 has not been updated for use with the MS5611. Changes
+ * were necessary to "calcPT()" in order to correct scaling of
+ * pressure readings.
+ *
+ * Features:
+ * Altitude resolution to 10cm
+ * Fast conversion down to 1 ms
+ * Low power, 1 μA (standby < 0.15 μA)
+ * QFN package 5.0 x 3.0 x 1.0 mm^3
+ * Supply voltage 1.8 to 3.6 V
+ * Integrated digital pressure sensor (24 bit DeltaSigma ADC)
+ * Operating range: 10 to 1200 mbar, -40 to +85 °C
+ * I2C and SPI interface up to 20 MHz
+ * No external components (Internal oscillator)
+ * Excellent long term stability
+ *
+ * @code
+ * #include "mbed.h"
+ * #include "ms5611.h"
+ *
+ * ms5611 ms(p9, p10); // i2c pins used
+ * Serial pc(USBTX, USBRX); // local terminal interface
+ *
+ *
+ * int main (void) {
+ * pc.baud(921600); // set up USB serial speed
+ *
+ * // set up the ms5611
+ * pc.printf("\n\nInitializing the MS5611..\n");
+ * ms.cmd_reset();
+ * pc.printf("Ready\n");
+ *
+ * while(1) {
+ * double Temp = ms.calcTemp(); //calculate press and temp, then returns current temperature in degC
+ * double Press = ms.calcPressure(); //calculate press and temp, then returns current pressure in mb
+ * double GetPress = ms.getPressure(); //returns current pressure in mb. Does no calculations. Ususally done after calcTemp()
+ * double Altitude = ms.getAltitudeFT(1013.25); //enter pressure at sea level in mb, returns altitude in feet
+ * double PressSeaLvlFT = ms.getSeaLevelBaroFT(327.2); //enter known altitude in feet, returns sea level pressure in mb
+ * double PressSeaLvlM = ms.getAltitudeFT(99.73); //enter known altitude in meters, returns seal level pressure in mb
+ *
+ * pc.printf("Temp: %.2f degC\n", Temp);
+ * pc.printf("Barometer: %.1f mB %.3f in/Hg\n", Press, Press * 0.0295301);
+ * pc.printf("Alt: %.1f ft\n", Altitude);
+ * pc.printf("Sea_Lvl: %.1f ft %.2f m\n", PressSeaLvlFT, PressSeaLvlM);
+ * wait(2.0);
+ * }
+ * }
+ *
+ * @endcode
+ */
+
+//_____ M A C R O S
+
+#define MS5611_ADDR_W 0xEE // Module address write mode
+#define MS5611_ADDR_R 0xEF // Module address read mode
+#define MS5611_CMD_RESET 0x1E // ADC reset command
+#define MS5611_CMD_ADC_READ 0x00 // ADC read command
+#define MS5611_CMD_ADC_CONV 0x40 // ADC conversion command
+#define MS5611_CMD_ADC_D1 0x00 // ADC D1 conversion
+#define MS5611_CMD_ADC_D2 0x10 // ADC D2 conversion
+#define MS5611_CMD_ADC_256 0x00 // ADC OSR=256
+#define MS5611_CMD_ADC_512 0x02 // ADC OSR=512
+#define MS5611_CMD_ADC_1024 0x04 // ADC OSR=1024
+#define MS5611_CMD_ADC_2048 0x06 // ADC OSR=2048
+#define MS5611_CMD_ADC_4096 0x08 // ADC OSR=4096
+#define MS5611_CMD_PROM_RD 0xA0 // Prom read command
+
+ /** Create ms5611 controller class
+ *
+ * @param ms5611 class
+ *
+ */
+class MS5611 {
+
+public:
+ /** Create a MS5611 object using the specified I2C object
+ *
+ * @param constructor, - the I2C object to communicate with
+ */
+ MS5611(PinName sda, PinName scl);
+ /** Initialize the MS5611 and set up the coefficients
+ * First - reset the MS5611
+ * Second - load coefficient values from the MS5611 PROM
+ * Third - calculate coefficient checksum
+ * This routine only needs to be run once at boot up
+ *
+ * @param NONE
+ */
+ void cmd_reset();
+ /** Calculate and return compensated temperature
+ * Returns double temperature in degC
+ *
+ * @param NONE
+ */
+ double calcTemp();
+ /** Calculate and return compensated barometric pressure
+ * Returns double pressure in millibars
+ *
+ * @param NONE
+ */
+ double calcPressure();
+ /** Return compensated barometric pressure
+ * Returns double pressure in millibars
+ * DOES NOT RE-CALCULATE FIRST!!!
+ * Saves time if you calcTemp(); first
+ *
+ * @param NONE
+ */
+ double getPressure();
+ /** Calculate and returns altitude in feet
+ * Returns float altitude in feet
+ *
+ * @param float known pressure (mB) at sea level
+ */
+ float getAltitudeFT(float sea_pressure);
+ /** Calculate and returns sea level baro
+ * Returns float seal level barometer in feet
+ *
+ * @param float known altitude in feet
+ */
+ float getSeaLevelBaroFT(float known_alt);
+ /** Calculate and returns sea level baro
+ * Returns float seal level barometer in meters
+ *
+ * @param float known altitude in meters
+ */
+ float getSeaLevelBaroM(float known_alt);
+
+private:
+ int m_i2c_start(bool readMode);
+ void m_i2c_stop(void);
+ unsigned char m_i2c_write(unsigned char data);
+ unsigned char m_i2c_readAck(void);
+ unsigned char m_i2c_readNak(void);
+ void m_i2c_send(char cmd);
+ void loadCoefs();
+ unsigned long cmd_adc(char cmd);
+ unsigned int cmd_prom(char coef_num);
+ unsigned char crc4(unsigned n_prom[]);
+ void calcPT();
+ unsigned int PTbuffer[8]; // calibration coefficients
+
+protected:
+ I2C _i2c;
+
+
+};
+#endif