Diff: main.cpp

Revision:

6:2c0e7ee70b8b

diff -r 34e9a3921278 -r 2c0e7ee70b8b main.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Nov 09 20:05:44 2012 +0000
@@ -0,0 +1,192 @@
+/*
+*
+* 1.8 - 3.6V (Vdd)
+* 1.62 - 3.6 (Vddio)
+*
+*
+*Altitude = 44330*(1-(p/p0)^(1/5.255))
+*   set p0 to sealevel pressure
+* delta p = 1hPa = 8.43m at sea level
+*
+*/
+
+/*
+*Pinout:
+*pin9  = SDA
+*pin10 = SCL
+*pin11 = XCLR (digital out; active low; Resets sensor)
+*pin12 = EOC ("end of conversation"; signal when conversion finished)
+*
+*/
+
+#include "mbed.h"
+#include "BMP085.h"
+
+I2C i2c(p9, p10); // sda, scl
+BMP085 alt_sensor(i2c);
+Serial pc(USBTX, USBRX); // tx, rx
+
+/*
+const int bmp085_address = 0xEE; //address of bmp085
+const int P0 = 101325; //pressure at sea level
+
+void bmp085_calibration(void);
+void display_calibration(void);
+unsigned short read_short(int,int);
+
+void write_char(int,int,int);
+
+long get_raw_temp(void);
+void calculations(long);
+
+float get_temperature(void);
+long get_pressure(void);
+float get_altitude(long);
+*/
+
+//short AC1, AC2, AC3, B1, B2, MB, MC, MD, OSS;
+//unsigned short  AC4, AC5, AC6;
+
+int main()
+{
+    pc.baud(9600);
+    //alt_sensor.display_cal_param(&pc);
+    while(1)
+    {
+        pc.printf("Temperature: %d\r\n", alt_sensor.get_temperature());
+        pc.printf("Pressure: %d\r\n", alt_sensor.get_pressure());
+        pc.printf("Altitude: %f\r\n", alt_sensor.get_altitude_ft());
+        
+        wait(0.5);
+    }
+    //Initialize
+    //OSS = STANDARD; //change between enums under bmp085_oss for desired Sampling resolution
+
+    //calibrate
+    //bmp085_calibration();
+    //display_calibration();
+
+    //long raw_temp = get_raw_temp();
+
+    //calculations(raw_temp);
+
+    //float altitude = get_altitude(pressure);
+
+    //pc.printf("Temperature: %f\n",temperature);
+    //pc.printf("Pressure: %l\n", pressure);
+    //pc.printf("Altitude: %f\n", altitude);
+}
+/*
+long get_raw_temp(void)
+{
+    long raw_temp;
+
+    //Read raw temperature value
+    write_char(bmp085_address, 0xF4, 0x2E);
+    wait_ms(4.5);
+    raw_temp = read_short(bmp085_address, 0xF6);
+
+    return raw_temp;
+}
+
+void calculations(long raw_temp)
+{
+    long X1, X2, B5; //temperature;
+
+    //Start temperature calculation
+    X1 = (((long)raw_temp - (long)AC6) * (long)AC5) >> 15;
+    X2 = ((long)MC << 11) / (X1 + MD);
+    B5 = X1 + X2;
+    temperature = ((B5 + 8) >> 4);
+
+    temperature = ((float)temperature / 10.0);
+
+    pc.printf("Temperature: %f\n",temperature);
+
+
+    long raw_pressure, B6, B3, X3;
+    unsigned long B4, B7;
+
+    //Read raw pressure value
+    write_char(bmp085_address, 0xf4, 0x34 | (OSS << 6));
+    wait_ms(5);
+    raw_pressure = read_short(bmp085_address, 0xF6) >> (8 - OSS);
+
+    //Start Pressure calculation
+    B6 = B5 - 4000;
+    X1 = (B2 * (B6 * B6) >> 12) >> 11;
+    X2 = (AC2 * B6) >> 11;
+    X3 = X1 + X2;
+    B3 = (((AC1 * 4 + X3) << OSS + 2) / 4);
+    X1 = (AC3 * B6) >> 13;
+    X2 = (B1 * ((B6 * B6) >> 12)) >> 16;
+    X3 = ((X1 + X2) + 2) >> 2;
+    B4 = (AC4 * (unsigned long)(X3 + 32768)) >> 15;
+    B7 = ((unsigned long)(raw_pressure - B3) * (50000 >> OSS));
+    if (B7 < 0x80000000)
+        pressure = (B7 *2) / B4;
+    else
+        pressure = (B7 / B4) * 2;
+
+    X1 = (pressure >> 8) * (pressure >>8);
+    X1 = (X1 * 3038) >>16;
+    X2 = (-7357 * pressure) >>16;
+    pressure += (X1 + X2 + 3791)>>4;
+
+    pc.printf("Pressure: %f\n", pressure);
+
+}
+
+float get_temperature(void)
+{
+    return temperature;
+}
+
+long get_pressure(void)
+{
+    return pressure;
+}
+
+float get_altitude(long pressure)
+{
+    float altitude;
+
+    altitude = (float)44330 * (1 - pow(( pressure/P0), 0.190295));
+
+    pc.printf("Altitude: %f\n", altitude);
+    return altitude;
+
+}
+
+void bmp085_calibration(void)
+{
+    AC1 = read_short(bmp085_address, 0xAA);
+    AC2 = read_short(bmp085_address, 0xAC);
+    AC3 = read_short(bmp085_address, 0xAE);
+    AC4 = read_short(bmp085_address, 0xB0);
+    AC5 = read_short(bmp085_address, 0xB2);
+    AC6 = read_short(bmp085_address, 0xB4);
+    B1  = read_short(bmp085_address, 0xB6);
+    B2  = read_short(bmp085_address, 0xB8);
+    MB  = read_short(bmp085_address, 0xBA);
+    MC  = read_short(bmp085_address, 0xBC);
+    MD  = read_short(bmp085_address, 0xBE);
+
+}
+
+void display_calibration(void)
+{
+    pc.printf("Calibration Values:\n");
+    pc.printf("AC1 = %d\n",AC1);
+    pc.printf("AC2 = %d\n",AC2);
+    pc.printf("AC3 = %d\n",AC3);
+    pc.printf("AC4 = %d\n",AC4);
+    pc.printf("AC5 = %d\n",AC5);
+    pc.printf("AC6 = %d\n",AC6);
+    pc.printf("B1 = %d\n",B1);
+    pc.printf("B2 = %d\n",B2);
+    pc.printf("MB = %d\n",MB);
+    pc.printf("MC = %d\n",MC);
+    pc.printf("MD = %d\n",MD);
+}*/
+