Revision 0:01659d3a8c37, committed 2016-12-11

Comitter:

otis22894

Date:

Sun Dec 11 21:12:09 2016 +0000

Commit message:

First commit

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MPL3115.cpp	Sun Dec 11 21:12:09 2016 +0000
@@ -0,0 +1,90 @@
+ /* Copyright (c) 2015 NXP Semiconductors. MIT License
+*
+* 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.
+*/
+
+#include "MPL3115.h"
+#include "mbed.h"
+#define REG_PRESSURE_MSB    0x01
+
+MPL3115::MPL3115(PinName sda, PinName scl, int addr) : MPL3115_i2c(sda,scl), m_addr(addr)
+ {
+       
+ }
+    
+ void MPL3115::config(void)
+ {
+   char d[2]; 
+   d[0] = MPL3115_CTRL_REG1;                     //Puts device in Standby mode
+   d[1] = 0x00; 
+   MPL3115_i2c.write(MPL3115_I2C_ADDRESS, d,2);   
+          
+   
+   d[0] = MPL3115_CTRL_REG1;                     //Puts device in Active mode and in altimeter mode
+   d[1] = 0x81;
+   MPL3115_i2c.write(MPL3115_I2C_ADDRESS, d, 2);   
+      
+ }
+ 
+
+ float MPL3115::getPressure(void)
+{
+    float a;
+    
+    a = getPressure(REG_PRESSURE_MSB);
+    return a;
+}
+ 
+ float MPL3115::getPressure(unsigned char reg)
+{
+    unsigned char dt[3];
+    unsigned int prs;
+    int tmp;
+    float fprs;
+    
+    /*
+    * dt[0] = Bits 12-19 of 20-bit real-time Pressure sample. (b7-b0)
+    * dt[1] = Bits 4-11 of 20-bit real-time Pressure sample. (b7-b0)
+    * dt[2] = Bits 0-3 of 20-bit real-time Pressure sample (b7-b4)
+    */
+    readRegs( reg, &dt[0], 3);
+    prs = ((dt[0]<<10) | (dt[1]<<2) | (dt[2]>>6));
+    //
+    if ( dt[0] > 0x7f) {
+        // negative number
+        if ( dt[0] & 0x80)
+            prs |= 0xFFFC0000;      
+        else
+            prs |= 0xFFFE0000;
+        tmp = ~prs + 1;             // make the complemets. At this point all the bits are inverted.
+        fprs = (float)tmp * -1.0f;  
+    } else {
+        fprs = (float)prs * 1.0f;
+    }
+ 
+    if ( dt[2] & 0x10)              
+        fprs += 0.25f;             
+    if ( dt[2] & 0x20)
+        fprs += 0.5f;
+        
+    return fprs;
+}
+ void MPL3115::readRegs(int addr, uint8_t * data, int len) {
+    char t[1] = {addr};
+    MPL3115_i2c.write(m_addr, t, 1, true);
+    MPL3115_i2c.read(m_addr, (char *)data, len);
+}
+ 
\ No newline at end of file

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MPL3115.h	Sun Dec 11 21:12:09 2016 +0000
@@ -0,0 +1,49 @@
+ /* Copyright (c) 2015 NXP Semiconductors. MIT License
+*
+* 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 MPL3115_H
+#define MPL3115_H
+#include "mbed.h"
+
+#define MPL3115_I2C_ADDRESS (0x60<<1)
+
+#define MPL3115_STATUS 0x00
+#define MPL3115_WHO_AM_I 0x0C
+#define MPL3115_CTRL_REG1 0x26
+#define MPL3115_CTRL_REG2 0x27
+#define MPL3115_WHO_AM_I_VALUE 0xC4
+
+class MPL3115
+{
+    public:
+    
+    MPL3115(PinName sda, PinName scl, int addr);
+      
+    void config(void);
+            
+    float getPressure(void);
+    float getPressure(unsigned char reg);
+    void readRegs(int addr, uint8_t * data, int len);
+
+    private:
+    I2C MPL3115_i2c;
+    int m_addr;
+    
+};
+
+#endif
\ No newline at end of file