Revision 7:90ee2168baa7, committed 2014-12-22

Comitter:

loopsva

Date:

Mon Dec 22 23:38:34 2014 +0000

Parent:

6:41c370fa1f7b

Child:

8:461f68bc94f2

Commit message:

Added second constructor so user can choose the polarity of the ms5611's CSB pin.

Changed in this revision

--- a/ms5611.cpp	Mon Jun 24 19:11:28 2013 +0000
+++ b/ms5611.cpp	Mon Dec 22 23:38:34 2014 +0000
@@ -24,10 +24,26 @@
 uint32_t C[8];                  //coefficient storage
 
 //--------------------------------------------------------------------------------------------------------------------------------------//
-// Constructor and destructor
+// Constructor and destructor - default to be compatible with legacy m5611 driver
 
 ms5611::ms5611(PinName sda, PinName scl)  : _i2c(sda, scl) {
         _i2c.frequency(400000);
+        _i2cWAddr = MS5611_ADDR_W;
+        _i2cRAddr = MS5611_ADDR_R;
+}
+
+//--------------------------------------------------------------------------------------------------------------------------------------//
+// Constructor and destructor - new, to allow for user to select i2c address based on CSB pin
+
+ms5611::ms5611(PinName sda, PinName scl, CSBpolarity CSBpin)  : _i2c(sda, scl) {
+        _i2c.frequency(400000);
+        _i2cWAddr = MS5611_ADDR_W;
+        _i2cRAddr = MS5611_ADDR_R;
+        if(CSBpin == CSBpin_1) {
+            _i2cWAddr -= 2;
+            _i2cRAddr -= 2;
+        
+        }
 }
 
 //********************************************************
@@ -40,9 +56,9 @@
     int twst;
     _i2c.start();
     if(readMode == true) {
-        twst = m_i2c_write(MS5611_ADDR_R);
+        twst = m_i2c_write(_i2cRAddr);
     } else {
-        twst = m_i2c_write(MS5611_ADDR_W);
+        twst = m_i2c_write(_i2cWAddr);
     }
     return(twst);
 }
@@ -142,7 +158,7 @@
     }
     m_i2c_send(MS5611_CMD_ADC_READ);
     
-    ret = _i2c.read(MS5611_ADDR_R, cobuf, 3, false);
+    ret = _i2c.read(_i2cRAddr, cobuf, 3, false);
     if(ret) printf("\n*** ms5611 ADC Read Error ");
     temp = (cobuf[0] << 16) + (cobuf[1] << 8) + cobuf[2];
     return temp;
@@ -161,7 +177,7 @@
     cobuf[0] = 0;
     cobuf[1] = 0;
     m_i2c_send(MS5611_CMD_PROM_RD + coef_num * 2); // send PROM READ command
-    ret = _i2c.read(MS5611_ADDR_R, cobuf, 2, false);
+    ret = _i2c.read(_i2cRAddr, cobuf, 2, false);
     if(ret) printf("\n*** ms5611 PROM Read Error ");
     rC = cobuf[0] * 256 + cobuf[1];
     return rC;

--- a/ms5611.h	Mon Jun 24 19:11:28 2013 +0000
+++ b/ms5611.h	Mon Dec 22 23:38:34 2014 +0000
@@ -41,7 +41,10 @@
  * #include "mbed.h"
  * #include "ms5611.h" 
  *
- * ms5611 ms(p9, p10);                        // i2c pins used
+ * //ms5611 ms(p9, p10);                        // i2c pins used
+ * ms5611 ms(p9, p10, ms5611::CSBpin_0);      // NEW!! with rev 7. User can set polarity of CSB pin
+ * //ms5611 ms(p9, p10, ms5611::CSBpin_1);
+ *
  * Serial pc(USBTX, USBRX);                   // local terminal interface
  *
  *
@@ -74,7 +77,7 @@
  
 //_____ M A C R O S
 
-#define MS5611_ADDR_W 0xEE // Module address write mode
+#define MS5611_ADDR_W 0xEE // Module address write mode (CSBpin = 0);
 #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
@@ -96,11 +99,27 @@
 class ms5611 {
 
 public:
+    enum CSBpolarity {
+        CSBpin_0,  //CSB pin is grounded, I2C address is 0xEE and 0xEF
+        CSBpin_1,  //CSB pin is tied to Vdd, I2C address is 0xEC and 0xED
+    };
     /** Create a MS5611 object using the specified I2C object
-     *
-     * @param constructor, - the I2C object to communicate with
+     *   - User fixed I2C address 0xEE, CSB pin = 0
+     *   - This is the default legacy constructor
+     * @param sda - mbed I2C interface pin
+     * @param scl - mbed I2C interface pin
      */
     ms5611(PinName sda, PinName scl);
+    /** Create a MS5611 object using the specified I2C object
+     *   - User defined use of the CSB pin
+     *   - CSB pin = 0, user set I2C address to 0xEE
+     *   - CSB pin = 1, user set I2C address to 0xEC 
+     * @param sda - mbed I2C interface pin
+     * @param scl - mbed I2C interface pin
+     * @param ms5611::CSBpin_0 - CSB pin tied to ground
+     * @param ms5611::CSBpin_1 - CSB pin tied to VDD
+     */
+    ms5611(PinName sda, PinName scl, CSBpolarity CSBpin);
     /** Initialize the MS5611 and set up the coefficients
      *    First - reset the MS5611
      *    Second - load coefficient values from the MS5611 PROM
@@ -150,6 +169,8 @@
     float getSeaLevelBaroM(float known_alt);
     
 private:
+    char _i2cWAddr;
+    char _i2cRAddr;
     int m_i2c_start(bool readMode);
     void m_i2c_stop(void);
     unsigned char m_i2c_write(unsigned char data);