main.cpp

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
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 #include "mbed.h"
00018 #include "BLEDevice.h"
00019 #include <string.h>
00020 
00021 #include "UARTService.h"
00022 
00023 #define NEED_CONSOLE_OUTPUT 1 /* Set this if you need debug messages on the console;
00024                                * it will have an impact on code-size and power consumption. */
00025 
00026 #if NEED_CONSOLE_OUTPUT
00027 #define DEBUG(...) { printf(__VA_ARGS__); }
00028 #else
00029 #define DEBUG(...) /* nothing */
00030 #endif /* #if NEED_CONSOLE_OUTPUT */
00031 
00032 #define ON 1960
00033 #define OFF 40
00034 #define PULSE_WIDTH 2000
00035 #define OUTPUT_LENGTH 35
00036 
00037 BLEDevice  ble;
00038 DigitalOut led1(LED1);
00039 DigitalOut led2(LED2);
00040 DigitalOut pwmOut(P0_30);
00041 
00042 AnalogIn ldr0(P0_1);
00043 AnalogIn ldr1(P0_2);
00044 AnalogIn ldr2(P0_3);
00045 AnalogIn ldr3(P0_4);
00046 
00047 int threshold = 0;
00048 
00049 //Output string to indicate the status of the LDRs
00050 char output[50] = "LDR0 = w x y z";
00051 
00052 UARTService *uartServicePtr;
00053 #define TIMER 0
00054 //Creating timer Instance
00055 
00056 Ticker ticker;
00057 #if TIMER
00058 long int timerCount = 0;
00059 #endif
00060 
00061 void disconnectionCallback(Gap::Handle_t handle, Gap::DisconnectionReason_t reason)
00062 {
00063     DEBUG("Disconnected!\n\r");
00064     DEBUG("Restarting the advertising process\n\r");
00065     ble.startAdvertising();
00066 }
00067 
00068 //Thresholding the values of the LDRs
00069 void getValuesofLDR()
00070 {
00071     if (ldr0.read() < 0.52f)
00072         output[7] = '0';
00073     else
00074         output[7] = '1';
00075     if (ldr0.read() < 0.52f)
00076         output[9] = '0';
00077     else
00078         output[9] = '1';
00079     if (ldr0.read() < 0.52f)
00080         output[11] = '0';
00081     else
00082         output[11] = '1';
00083     if (ldr0.read() < 0.52f)
00084         output[13] = '0';
00085     else
00086         output[13] = '1';
00087  
00088 }
00089 
00090 //Preparation of output string
00091 void onDataWritten(const GattCharacteristicWriteCBParams *params)
00092 {
00093     char *str = 0;
00094     int count = 0;
00095 
00096     if ((uartServicePtr != NULL) && (params->charHandle == uartServicePtr->getTXCharacteristicHandle())) {
00097         uint16_t bytesRead = params->len;
00098         DEBUG("received %u bytes\n\r", bytesRead);
00099         
00100         //Obtaining user command
00101         str = (char *)malloc((sizeof(char) * bytesRead) + 1);
00102         while(count <= bytesRead)
00103         {
00104             *(str + count) = *(params->data + count);
00105             count++;
00106         }
00107         count--;
00108         *(str + count) = '\0';
00109         DEBUG("payload = %s\n\r",str);
00110         
00111         //Comparing user input against keywords
00112         if (strncmp(str,"On",bytesRead) == 0)
00113         {
00114             led2 = 0;
00115             pwmOut = 0;
00116             bytesRead = 7;
00117             strncpy((char *)params->data,"Lamp On", bytesRead);
00118         }    
00119         else if (strncmp(str,"Off",bytesRead) == 0)
00120         {
00121             led2 = 1;
00122             pwmOut = 1;
00123             bytesRead = 8;
00124             strncpy((char *)params->data,"Lamp Off", bytesRead);
00125         }
00126         else if (strncmp(str,"Read",bytesRead) == 0)
00127         {
00128             bytesRead = 13;
00129             getValuesofLDR();    
00130             strncpy((char *)params->data,output,bytesRead);
00131             
00132         }
00133         else//None of the commands match. Invalid entry
00134         {
00135             bytesRead = 14;
00136             strncpy((char *)params->data,"Invalid Entry", bytesRead);
00137         }    
00138         free(str);
00139         ble.updateCharacteristicValue(uartServicePtr->getRXCharacteristicHandle(), params->data, bytesRead);
00140     }
00141 }
00142 
00143 void periodicCallback(void)
00144 {
00145 #if TIMER
00146     timerCount++;
00147     if ((timerCount < threshold))
00148     {
00149             led1 = 1;
00150             pwm_out = 1;
00151     }
00152     else
00153     {
00154             led1 = 0;    
00155             pwm_out = 0;
00156     }       
00157     if (timerCount == PULSE_WIDTH)
00158         timerCount = 0;
00159 #else
00160     led1 = !led1;
00161 #endif
00162 
00163 }
00164 
00165 int main(void)
00166 {
00167     led1 = 1;
00168     DEBUG("Initialising the nRF51822\n\r");
00169     //ticker.attach(periodicCallback, 0.00001f);
00170     ble.init();
00171     
00172     ble.onDisconnection(disconnectionCallback);
00173 
00174     ble.onDataWritten(onDataWritten);
00175     
00176     /* setup advertising */
00177     ble.accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED);
00178     ble.setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED);
00179     ble.accumulateAdvertisingPayload(GapAdvertisingData::SHORTENED_LOCAL_NAME,
00180                                      (const uint8_t *)"AdarshBLE UART", sizeof("AdarshBLE UART") - 1);
00181     ble.accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LIST_128BIT_SERVICE_IDS,
00182                                      (const uint8_t *)UARTServiceUUID_reversed, sizeof(UARTServiceUUID_reversed));
00183 
00184     ble.setAdvertisingInterval(160); /* 100ms; in multiples of 0.625ms. */
00185     ble.startAdvertising();
00186 
00187     UARTService uartService(ble);
00188     uartServicePtr = &uartService;
00189     
00190     while (true) {
00191         ble.waitForEvent();
00192     }
00193 }