Diff: MCP9808.cpp

Revision:

0:46326feade89

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/MCP9808.cpp	Tue Apr 12 09:02:48 2016 +0000
@@ -0,0 +1,60 @@
+#include "MCP9808.h"
+
+//***********************************/************************************
+//                              Constant                                //
+//***********************************/************************************
+#define MCP9808_I2C_ADDR    0x30 //( 18<<1)
+
+#define MCP9808_REG_CONFIG  0x01
+#define MCP9808_REG_TUPPER  0x02
+#define MCP9808_REG_TLOWER  0x03
+#define MCP9808_REG_TCRIT   0x04
+#define MCP9808_REG_TAMB    0x05
+#define MCP9808_REG_MANID   0x06
+#define MCP9808_REG_DEVID   0x07
+#define MCP9808_REG_RESOL   0x08
+
+#define MCP9808_TAMB_MASK   0x0F
+#define MCP9808_SIGN_POS    0x03
+
+//***********************************/************************************
+//                         Constructors                                 //
+//***********************************/************************************
+MCP9808::MCP9808(I2C *i2c, bool a0, bool a1, bool a2):_i2c(i2c)
+{
+    _addr = (MCP9808_I2C_ADDR | (a2<<3) | (a1<<2) | (a0<<1));
+}
+
+float MCP9808::getTemp(void)
+{
+    char reg = MCP9808_REG_TAMB;
+    float ta;
+    char buf[2];
+
+    _i2c->write(_addr, &reg, 1);
+    _i2c->read(_addr, buf, 2);
+    
+    /*
+    if(buf[0] & (1<<MCP9808_SIGN_POS))
+    {
+        buf[0] &= MCP9808_TAMB_MASK;
+        
+        ta = 256 - (buf[0]*16 + buf[1]*0.0625); 
+    }
+    else
+    {
+        buf[0] &= MCP9808_TAMB_MASK;
+        ta = (buf[0]*16 + buf[1]*0.0625);
+    }*/
+    
+    ta = ((buf[0]&MCP9808_TAMB_MASK) << 8) | buf[1];
+    ta /= 16.0;
+    
+    if(buf[0] & (1<<MCP9808_SIGN_POS))
+    {
+        ta -= 256;
+    }
+      
+    return ta;  
+}
+