main.cpp

00001 /*********************************
00002 **Read DS1624 Temperature Sensor**
00003 ******Made by Stijn Sontrop*******
00004 **********22 Dec 2010*************
00005 **********************************/
00006 
00007 #include "mbed.h"
00008 #include <TextLCD.h> //Include the TextLCD lib (add this one to your project)
00009 
00010 
00011 //Address of DS1642: 1001 A2 A1 A0 R/W'
00012 //Example: 0x92 = Sensor with address 1
00013 //Make R/W' 0
00014 #define DS1642WRITEADDR 0x92
00015 //Make R/W' 1
00016 #define DS1642READADDR 0x93
00017 
00018 TextLCD lcd(p15, p16, p17, p18, p19, p20); //LCD Config rs, e, d4-d7
00019 
00020 I2C i2c(p9, p10); //SDA & SCL from I2C
00021 typedef struct { //Struct that contains the MSB en LSB value
00022     char msb;
00023     char lsb;
00024 } temperature;
00025 
00026 //Function that reads the temperature
00027 temperature readDS1624(void) {
00028     temperature readval;
00029     i2c.start();
00030     i2c.write(DS1642WRITEADDR); //address
00031     i2c.write(0xEE); //start conv T
00032     i2c.stop();
00033     wait_ms(2);
00034     
00035     i2c.start();
00036     i2c.write(DS1642WRITEADDR); //Address
00037     i2c.write(0xAA); //read temp command
00038     i2c.stop();
00039     wait_ms(1);
00040     
00041     i2c.start();
00042     i2c.write(DS1642READADDR); //Write Address
00043     readval.msb = i2c.read(1); //Read MSB + ACK
00044     readval.lsb = i2c.read(0); //Read LSB + No ACK
00045     i2c.stop();
00046     readval.msb = readval.msb - 2; //Apparently you need to do -2 to get the right value
00047     return readval; //Return value
00048 }
00049 
00050 int main() {
00051     temperature readval;
00052     i2c.start();
00053     i2c.write(DS1642WRITEADDR); //b1001 A2 A1 A0 R/W'
00054     i2c.write(0xAC); //access config
00055     i2c.write(0x00); //continuous conversion
00056     i2c.stop();
00057     
00058     while (1) {
00059         readval = readDS1624(); //Call the readDS162 function
00060         lcd.cls(); //Clear LCD
00061         lcd.printf("Temp: %d\n%d", readval.msb, readval.lsb); //Print values to LCD
00062         wait(0.3);
00063     }
00064 }