TempSensor_LM75B_test.cpp

00001 /*
00002  *  I2C digital temperature sensor "LM75B" library test app
00003  *
00004  *  LM75B is an I2C based digital temperature sensor
00005  *  http://www.nxp.com/pip/LM75B_2.html
00006  *
00007  *   Expecting to use the pins 9 and 10 for I2C bus
00008  *   these pins should be pulled-up properly.
00009  *
00010  *   The temperature read out will be shown on terminal on the PC screen.
00011  *
00012  *   In this demo code, two LM75B devices can be driven.
00013  *   These two devices should have different I2C address setting
00014  *   using its address pins (LM75B's A0 to A2 (pins 5 to 7)).
00015  *   One LM75B should have all those pins tied to GND.
00016  *   And another should have the pin A0(pin7) pulled-up.
00017  *
00018  *   From the software, those devices can be accessed by I2C addresses
00019  *   "0x90" and "0x92".
00020  *   It will not be as "0x90" and "0x91" because the address has
00021  *   7 bit only and stuffed to left. So the "A0" setting become 0xX2.
00022  *   The LSB does not care because it will be set by I2C libraly when
00023  *   it transfer the data for read and write.
00024  *
00025  *   This code is new version that can handle the LM75B are the objects.
00026  *
00027  *  Copyright (c) 2010 Tedd OKANO
00028  *  Released under the MIT License: http://mbed.org/license/mit
00029  *
00030  *  revision 1.0  16-Jan-2010   a. 1st release
00031  *  revision 1.1  23-Jan-2010   a. class name has been changed from LM75B to TempSensor_LM75B
00032  *                              b. copyright notice added
00033  */
00034 
00035 #include "mbed.h"
00036 #include "TempSensor_LM75B.h"
00037 
00038 Serial       pc(USBTX, USBRX); // tx, rx
00039 
00040 I2C          i2c( p9, p10 );        // sda, scl
00041 
00042 TempSensor_LM75B        thermo_sensor_0( &i2c );        //  sensor_0 using with default I2C address "0x90".
00043 TempSensor_LM75B        thermo_sensor_1( &i2c, 0x92 );  //  sensor_1 gaved I2C address since that address pin A0=HIGH.
00044 
00045 int main() {
00046     int    i    = 0;
00047 
00048     while (1) {
00049         pc.printf( "  (%d)  sensor_0= %4.1f,  sensor_1= %4.1f(degree-C)\n", i++, (float)thermo_sensor_0, (float)thermo_sensor_1 );
00050         wait( 1 );
00051     }
00052 }
00053