TestTemperature.cpp

00001 /*
00002  *  Copyright 2013 Embedded Artists AB
00003  *
00004  *  Licensed under the Apache License, Version 2.0 (the "License");
00005  *  you may not use this file except in compliance with the License.
00006  *  You may obtain a copy of the License at
00007  *
00008  *    http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  *  Unless required by applicable law or agreed to in writing, software
00011  *  distributed under the License is distributed on an "AS IS" BASIS,
00012  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  *  See the License for the specific language governing permissions and
00014  *  limitations under the License.
00015  */
00016 
00017 /******************************************************************************
00018  * Includes
00019  *****************************************************************************/
00020 
00021 #include "mbed.h"
00022 #include "TestTemperature.h"
00023 #include "LM75B.h"
00024 
00025 /******************************************************************************
00026  * Defines and typedefs
00027  *****************************************************************************/
00028 
00029 #define MIN_TEMP  (15.0f)
00030 #define MAX_TEMP  (45.0f)
00031 
00032 /******************************************************************************
00033  * Public Functions
00034  *****************************************************************************/
00035 
00036 /*
00037    Prerequisites:
00038  
00039    - For this test to work jumpers JP8 and JP9 on the LPC4088 Experiment Base Board
00040      must both be in positions 1-2
00041 */
00042 
00043 bool TestTemperature::runTest() {
00044     //Create an LM75B object at 0x92/0x93 (ADDRESS_1)
00045     LM75B sensor(P0_27, P0_28, LM75B::ADDRESS_1);
00046 
00047     printf("Testing LM75 temperature sensor...\n");
00048 
00049     // Test waits up to 5 seconds, sampling the temperature twice per second,
00050     // for the sensor to produce a value in the MIN_TEMP to MAX_TEMP range.
00051     
00052     if (sensor.open()) {
00053         printf("LM75 Device detected!\n");
00054  
00055         int i = 10;
00056         while (i--) {
00057             float f = (float)sensor;
00058 
00059             printf("Temp = %.3f\n", f);
00060  
00061             if ((f >= MIN_TEMP) && (f <= MAX_TEMP)) {
00062                 printf("Temp in %.3f..%.3f range - test passed\n", MIN_TEMP, MAX_TEMP);
00063                 return true;
00064             }
00065             
00066             //Sleep for 0.5 seconds
00067             wait(0.5);
00068         }
00069         if (i == 0) {
00070             printf("LM75 No temp in range %.3f..%.3f!\n", MIN_TEMP, MAX_TEMP);
00071         }
00072     } else {
00073         printf("LM75 Device not detected!\n");
00074     }  
00075     return false;
00076 }
00077 
00078