Revision 0:adf5a063372d, committed 2014-07-31

Comitter:

yangcq88517

Date:

Thu Jul 31 13:52:49 2014 +0000

Commit message:

SRF02

Changed in this revision

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SRF02.cpp	Thu Jul 31 13:52:49 2014 +0000
@@ -0,0 +1,58 @@
+#include "SRF02.h"
+
+SRF02::SRF02(uint8_t I2C_address,PinName sda, PinName scl): i2c_bus(sda,scl)
+{
+    deviceAddess =   I2C_address;
+}
+
+int SRF02::GetValue(uint8_t command, uint8_t mode)
+{
+    char w[2]= {COMMAND_REGISTER,command};
+    if (i2c_bus.write(deviceAddess,w ,2)>=0)
+        wait(DefaultWait);
+    else return -1;
+    char r[1] = {mode};
+    if (i2c_bus.write(deviceAddess,r ,1)>=0)
+        if (i2c_bus.read(deviceAddess, w, 2)>=0)
+            return (w[0] << 8) | w[1];
+    return -1;
+}
+
+int SRF02::GetMinimumRange()
+{
+    return GetValue(REAL_RANGING_CENTIMETERS,Autotune);
+}
+
+int SRF02::GetCentimeters()
+{
+    return GetValue(REAL_RANGING_CENTIMETERS,Range);
+}
+
+int SRF02::GetInches()
+{
+    return GetValue(REAL_RANGING_INCHES,Range);
+}
+
+int SRF02::GetMicroSeconds()
+{
+    return GetValue(REAL_RANGING_SECONDS,Range);
+}
+
+bool SRF02::ChangeAddress(uint8_t newAddress)
+{
+    char w[2]= {COMMAND_REGISTER,0xA0};
+    if (i2c_bus.write(deviceAddess,w ,2)>=0)
+        w[1] = 0xAA;
+    else return false;
+    if (i2c_bus.write(deviceAddess,w ,2)>=0)
+        w[1] = 0xA5;
+    else return false;
+    if (i2c_bus.write(deviceAddess,w ,2)>=0)
+        w[1] = newAddress;
+    else return false;
+    if (i2c_bus.write(deviceAddess,w ,2)>=0) {
+        deviceAddess = newAddress;
+        return true;
+    }
+    return false;
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/SRF02.h	Thu Jul 31 13:52:49 2014 +0000
@@ -0,0 +1,42 @@
+#ifndef Smartlab_Drive_SPRF02
+#define Smartlab_Drive_SPRF02
+
+#include "mbed.h"
+
+class SRF02
+
+{
+private:
+    uint8_t deviceAddess;
+    static const int CLOCK_RATE = 100000;
+
+    static const uint8_t COMMAND_REGISTER = 0x00;
+    
+    static const uint8_t Range = 0x02;
+    static const uint8_t Autotune  = 0x04;
+    
+    static const uint8_t REAL_RANGING_INCHES = 0x50;
+    static const uint8_t REAL_RANGING_CENTIMETERS = 0x51;
+    static const uint8_t REAL_RANGING_SECONDS = 0x52;
+
+    static const float DefaultWait = 0.07;
+
+    I2C i2c_bus;
+    
+    int GetValue(uint8_t command, uint8_t mode);
+
+public :
+    SRF02(uint8_t I2C_address,PinName sda, PinName scl);
+
+    int GetMinimumRange();
+
+    int GetCentimeters();
+
+    int GetInches();
+
+    int GetMicroSeconds();
+    
+    bool ChangeAddress(uint8_t newAddress);
+};
+
+#endif
\ No newline at end of file