MS5607 Parallax micro altimeter module interfaces (I2C & SPI)

Dependents:   MS5607Example Vertex_Integration_4 Time_MS5607_Pressure Time_MS5607_Temperature ... more

Files at this revision

API Documentation at this revision

Comitter:
yamaguch
Date:
Tue Jul 03 08:57:57 2012 +0000
Commit message:
0.92

Changed in this revision

MS5607Base.h Show annotated file Show diff for this revision Revisions of this file
MS5607I2C.h Show annotated file Show diff for this revision Revisions of this file
MS5607SPI.h Show annotated file Show diff for this revision Revisions of this file
diff -r 000000000000 -r 5760862143d1 MS5607Base.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MS5607Base.h	Tue Jul 03 08:57:57 2012 +0000
@@ -0,0 +1,121 @@
+/*
+Copyright (c) 2012, Senio Networks, Inc.
+
+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.
+*/
+
+#ifndef MS5607_BASE_H
+#define MS5607_BASE_H
+
+class MS5607Base {
+public:
+    void printCoefficients() {
+        printf("%d, %d, %d, %d, %d, %d\n", c1, c2, c3, c4, c5, c6);
+    }
+
+    int getRawTemperature() {
+        return readADC(ADC_D2 | OSR_4096);
+    }
+
+    int getRawPressure() {
+        return readADC(ADC_D1 | OSR_4096);
+    }
+
+    float getTemperature() {
+        int dT = getRawTemperature() - (c5 << 8);
+        int temp = 2000 + ((dT * c6) >> 23);
+        
+        // 2nd order temperature compensation
+        if (temp < 2000) {
+            int t2 = (int64_t) dT * dT >> 31;
+            temp -= t2;
+        }
+
+        return float(temp) / 100;
+    }
+
+    float getPressure() {
+        int dT = getRawTemperature() - (c5 << 8);
+        int temp = 2000 + ((dT * c6) >> 23);
+        int64_t off = ((int64_t) c2 << 17) + ((int64_t) dT * c4 >> 6);
+        int64_t sens = ((int64_t) c1 << 16) + ((int64_t) dT * c3 >> 7);
+
+        // 2nd order temperature compensation
+        if (temp < 2000) {
+            int64_t off2 = (int64_t) 61 * (temp - 2000) * (temp - 2000) >> 4;
+            int64_t sens2 = (int64_t) 2 * (temp - 2000) * (temp - 2000);
+            if (temp < -1500) {
+                off2 += (int64_t) 15 * (temp + 1500) * (temp + 1500);
+                sens2 += (int64_t) 8 * (temp + 1500) * (temp + 1500);
+            }
+            off -= off2;
+            sens -= sens2;
+        }
+
+        return float((((int64_t) getRawPressure() * sens >> 21) - off) >> 15);
+    }
+
+    float getAltitude(int presssure = 0) {
+        return toAltitude(presssure ? presssure : (int) getPressure());
+    }
+
+protected:
+    int32_t c1, c2, c3, c4, c5, c6;
+
+    enum {
+        RESET     = 0x1E,
+        ADC_READ  = 0x00,
+        ADC_CONV  = 0x40,
+        ADC_D1    = 0x00,
+        ADC_D2    = 0x10,
+        OSR_256   = 0x00,
+        OSR_512   = 0x02,
+        OSR_1024  = 0x04,
+        OSR_2048  = 0x06,
+        OSR_4096  = 0x08,
+        PROM_READ = 0xA0
+    };
+
+    virtual void writeCommand(int command, int ms = 0) = 0;
+    virtual int readPROM(int address) = 0;
+    virtual int readADC(int command) = 0;
+
+    void init() {
+        writeCommand(RESET, 3);
+        c1 = readPROM(1);
+        c2 = readPROM(2);
+        c3 = readPROM(3);
+        c4 = readPROM(4);
+        c5 = readPROM(5);
+        c6 = readPROM(6);
+    }
+
+    float toAltitude(int pressure) {
+        // Ref. 29124-AltimeterAppNote1.pdf
+        const float R = 287.052; // specific gas constant R*/M0
+        const float g = 9.80665; // standard gravity 
+        const float t_grad = 0.0065; // gradient of temperature
+        const float t0 = 273.15 + 15; // temperature at 0 altitude
+        const float p0 = 101325; // pressure at 0 altitude
+
+        return t0 / t_grad * (1 - exp((t_grad * R / g) * log(pressure / p0)));
+    }
+};
+
+#endif
\ No newline at end of file
diff -r 000000000000 -r 5760862143d1 MS5607I2C.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MS5607I2C.h	Tue Jul 03 08:57:57 2012 +0000
@@ -0,0 +1,71 @@
+/*
+Copyright (c) 2012, Senio Networks, Inc.
+
+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.
+*/
+
+#ifndef MS5607_I2C_H
+#define MS5607_I2C_H
+
+#include "MS5607Base.h"
+
+class MS5607I2C : public MS5607Base {
+public:
+    MS5607I2C(PinName sda, PinName scl, int csb = 0) : i2c(sda, scl), i2cAddr(csb ? 0xEC : 0xEE) {
+        init();
+    }
+
+private:
+    I2C i2c;
+    int i2cAddr;
+
+    virtual void writeCommand(int command, int ms = 0) {
+        char buf[1] = {command};
+        i2c.write(i2cAddr, buf, 1);
+        if (ms) wait_ms(ms);
+    }
+
+    virtual int readPROM(int address) {
+        char buf[2] = {PROM_READ | (address << 1), 0};
+
+        if (i2c.write(i2cAddr, buf, 1) == 0 &&
+            i2c.read(i2cAddr, buf, 2) == 0)
+            return buf[0] << 8 | buf[1];
+
+        return -1;
+    }
+
+    virtual int readADC(int command) {
+        char cmd[] = {ADC_CONV | command};
+
+        if (i2c.write(i2cAddr, cmd, sizeof(cmd)) == 0) {
+            static int duration[] = {500, 1100, 2100, 4100, 8220};
+            wait_us(duration[(command & 0x0F) >> 1]);
+            cmd[0] = ADC_READ;
+            char buf[3];
+            if (i2c.write(i2cAddr, cmd, sizeof(cmd)) == 0 &&
+                i2c.read(i2cAddr, buf, sizeof(buf)) == 0)
+                return buf[0] << 16 | buf[1] << 8 | buf[2];
+        }
+
+        return -1;
+    }
+};
+
+#endif
\ No newline at end of file
diff -r 000000000000 -r 5760862143d1 MS5607SPI.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MS5607SPI.h	Tue Jul 03 08:57:57 2012 +0000
@@ -0,0 +1,70 @@
+/*
+Copyright (c) 2012, Senio Networks, Inc.
+
+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.
+*/
+
+#ifndef MS5607_SPI_H
+#define MS5607_SPI_H
+
+#include "MS5607Base.h"
+
+class MS5607SPI : public MS5607Base {
+public:
+    MS5607SPI(PinName mosi, PinName miso, PinName sclk, PinName csb) : spi(mosi, miso, sclk), csb(csb) {
+        init();
+    }
+
+private:
+    SPI spi;
+    DigitalOut csb;
+
+    virtual void writeCommand(int command, int ms = 0) {
+        csb = 0;
+        spi.write(command);
+        if (ms) wait_ms(ms);
+        csb = 1;
+    }
+
+    virtual int readPROM(int address) {
+        csb = 0;
+        spi.write(PROM_READ | address << 1);
+        int hi = spi.write(0);
+        int low = spi.write(0);
+        csb = 1;
+        return hi << 8 | low;
+    }
+
+    virtual int readADC(int command) {
+        csb = 0;
+        spi.write(ADC_CONV | command);
+        static int duration[] = {500, 1100, 2100, 4100, 8220};
+        wait_us(duration[(command & 0x0F) >> 1]);
+        csb = 1;
+        csb = 0;
+        spi.write(ADC_READ);
+        int hi = spi.write(0);
+        int mid = spi.write(0);
+        int low = spi.write(0);
+        csb = 1;
+        return hi << 16 | mid << 8 | low;
+    }
+};
+
+#endif
\ No newline at end of file