Diff: main.cpp

Revision:

0:5b140ed159a9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed May 04 05:50:35 2011 +0000
@@ -0,0 +1,73 @@
+
+#include "mbed.h"
+
+I2C i2c(p28,p27);   //sda,scl
+Serial pc(USBTX,USBRX);  //serial usb config
+
+char a[5];
+
+int main()
+{
+  int p1,p2,p3;          //to store adc high and low and PEC(packet error correction)
+  int ch=0,temp_val;     //to store temparature value
+  i2c.frequency(20000);  //I2C frequency 20000hz (20khz)
+  
+  
+  while(1){
+
+  do{                               //loop repeat if repeated start codition is not acknowledge
+                      
+                      do{            //loop repeat if device ram address(reg address where the Tobj value present) condition is not acknowledge
+                      
+                                                                 
+                                  
+                                  do{                       //loop repeat if device address acdition is not acknowledge
+                                       pc.printf("add\t");   
+                                         i2c.stop();          //stop i2c if not ack
+                                    
+                                    wait(0.2);
+                                  i2c.start();                  //start I2C                   
+                                        ch=i2c.write(0x00);     //device address of mlxIRtemprature sensorwith write condition
+                                      } while(ch==0);          //wait for ack
+                                  pc.printf("ACK1\t");           
+                                  
+                                  ch=i2c.write(0x07);          //device ram address where Tobj value is present
+                       } while(ch==0);                          //wait for ack
+                      pc.printf("ACK2\t");
+                      
+                      
+                     
+                         i2c.start();                         //repeat start
+                         ch=i2c.write(0x01);                  //device address with read condition   
+        }while(ch==0);                                          //wait for ack
+         pc.printf("ACK3\t");
+         p1=i2c.read(1);                            //Tobj low byte
+        p2=i2c.read(1);                               //Tobj heigh byte
+        p3=i2c.read(0);                                //PEC
+        i2c.stop();                                 //stop condition
+     
+                                                            //degree centigrate conversion
+     temp_val=((((p2&0x007f)<<8)+p1)*0.02)-0.01;
+     temp_val=temp_val-273;                    
+     
+  
+ 
+   wait(1.0); 
+
+  
+   pc.printf("rx val1 is %d\n",p1);
+  pc.printf("rx val2 is %d\n",p2);
+   pc.printf("rx val3 is %d\n",p3);
+  pc.printf("temp val is %d\n",temp_val); 
+
+  
+  wait(2.0);
+   
+
+   
+  } 
+  
+ 
+  
+  return 0;
+}