Mert Kaya
BLE code for touch signal
Dependencies: BLE_API mbed nRF51822
Fork of
BLE_GATT_Example
by 
Bluetooth Low Energy
Diff: main.cpp
- Revision:
- 23:721f64d359ff
- Parent:
- 22:406127954d1f
--- a/main.cpp Mon Nov 09 17:08:47 2015 +0000
+++ b/main.cpp Thu Jun 29 19:44:59 2017 +0000
@@ -1,104 +1,337 @@
#include "mbed.h"
#include "ble/BLE.h"
-DigitalOut led(LED1, 1);
+#define THRESHOLD_PRESS 0.08
+#define TIME_BETWEEN_TOUCH 0.05
+#define TIME_BETWEEN_CYCLE 0.1
+
+#define LEFT_PUSH 1
+#define RIGHT_PUSH 2
+#define LEFT_SWIPE 3
+#define RIGHT_SWIPE 4
+
+/* Four capacitive touch inputs; active low
+ * Two on the left, two on the right, all in one row */
+DigitalIn touch1(P0_12);
+DigitalIn touch2(P0_13);
+DigitalIn touch3(P0_14);
+DigitalIn touch4(P0_15);
+
+/* One pressure sensor input */
+AnalogIn press(P0_1);
+
+/* One haptic input */
+/* PwmOut haptic(P0_16); */
+
+/* Choose custom GATT UUIDS and profile name */
uint16_t customServiceUUID = 0xA000;
uint16_t readCharUUID = 0xA001;
-uint16_t writeCharUUID = 0xA002;
+const static char DEVICE_NAME[] = "Touch Signal";
+static const uint16_t uuid16_list[] = {0xA000}; /* Custom UUID, FFFF is reserved for development */
-const static char DEVICE_NAME[] = "ChangeMe!!"; // change this
-static const uint16_t uuid16_list[] = {0xFFFF}; //Custom UUID, FFFF is reserved for development
+/* Variable used to search for inputs every 0.3 seconds and prevent connection timeout */
+static volatile bool triggerSensorPolling = false;
-/* Set Up custom Characteristics */
-static uint8_t readValue[10] = {0};
-ReadOnlyArrayGattCharacteristic<uint8_t, sizeof(readValue)> readChar(readCharUUID, readValue);
+/* Ouput variable */
+uint8_t readSignal = 0;
-static uint8_t writeValue[10] = {0};
-WriteOnlyArrayGattCharacteristic<uint8_t, sizeof(writeValue)> writeChar(writeCharUUID, writeValue);
+/* Set up custom read characteristic*/
+ReadOnlyGattCharacteristic<uint8_t> readChar(readCharUUID, &readSignal, GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY);
/* Set up custom service */
-GattCharacteristic *characteristics[] = {&readChar, &writeChar};
+GattCharacteristic *characteristics[] = {&readChar};
GattService customService(customServiceUUID, characteristics, sizeof(characteristics) / sizeof(GattCharacteristic *));
-
-/*
- * Restart advertising when phone app disconnects
-*/
-void disconnectionCallback(const Gap::DisconnectionCallbackParams_t *)
-{
+/* Restart advertising when phone app disconnects */
+void disconnectionCallback(const Gap::DisconnectionCallbackParams_t *){
BLE::Instance(BLE::DEFAULT_INSTANCE).gap().startAdvertising();
}
-/*
- * Handle writes to writeCharacteristic
-*/
-void writeCharCallback(const GattWriteCallbackParams *params)
-{
- /* Check to see what characteristic was written, by handle */
- if(params->handle == writeChar.getValueHandle()) {
- /* toggle LED if only 1 byte is written */
- if(params->len == 1) {
- led = params->data[0];
- (params->data[0] == 0x00) ? printf("led on\n\r") : printf("led off\n\r"); // print led toggle
- }
- /* Print the data if more than 1 byte is written */
- else {
- printf("Data received: length = %d, data = 0x",params->len);
- for(int x=0; x < params->len; x++) {
- printf("%x", params->data[x]);
- }
- printf("\n\r");
- }
- /* Update the readChar with the value of writeChar */
- BLE::Instance(BLE::DEFAULT_INSTANCE).gattServer().write(readChar.getValueHandle(), params->data, params->len);
- }
+void periodicCallback(void){
+ /* Note that the periodicCallback() executes in interrupt context, so it is safer to do
+ * heavy-weight sensor polling from the main thread. */
+ triggerSensorPolling = true;
}
-/*
- * Initialization callback
- */
-void bleInitComplete(BLE::InitializationCompleteCallbackContext *params)
-{
+
+/* Initialization callback */
+void bleInitComplete(BLE::InitializationCompleteCallbackContext *params){
BLE &ble = params->ble;
ble_error_t error = params->error;
-
- if (error != BLE_ERROR_NONE) {
+ if(error != BLE_ERROR_NONE){
return;
}
-
ble.gap().onDisconnection(disconnectionCallback);
- ble.gattServer().onDataWritten(writeCharCallback);
-
/* Setup advertising */
- ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED | GapAdvertisingData::LE_GENERAL_DISCOVERABLE); // BLE only, no classic BT
- ble.gap().setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED); // advertising type
- ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LOCAL_NAME, (uint8_t *)DEVICE_NAME, sizeof(DEVICE_NAME)); // add name
- ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LIST_16BIT_SERVICE_IDS, (uint8_t *)uuid16_list, sizeof(uuid16_list)); // UUID's broadcast in advertising packet
- ble.gap().setAdvertisingInterval(100); // 100ms.
-
- /* Add our custom service */
+ ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED | GapAdvertisingData::LE_GENERAL_DISCOVERABLE); /* BLE only, no classic BT */
+ ble.gap().setAdvertisingType(GapAdvertisingParams::ADV_CONNECTABLE_UNDIRECTED); /* Advertising type */
+ ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LOCAL_NAME, (uint8_t *)DEVICE_NAME, sizeof(DEVICE_NAME)); /* Add name */
+ ble.gap().accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LIST_16BIT_SERVICE_IDS, (uint8_t *)uuid16_list, sizeof(uuid16_list)); /* UUID's broadcast in advertising packet */
+ ble.gap().setAdvertisingInterval(300); /* 300 ms */
+ /* Add custom service */
ble.addService(customService);
-
/* Start advertising */
ble.gap().startAdvertising();
}
-/*
- * Main loop
-*/
-int main(void)
-{
- /* initialize stuff */
- printf("\n\r********* Starting Main Loop *********\n\r");
+void pressed(){
+ /* Check which side of capacitive touch pad is being touched */
+ if((touch1 == 0 || touch2 == 0) && (touch3 == 1 && touch4 == 1)){
+ /* Left push
+ * Success buzz */
+ readSignal = LEFT_PUSH;
+ }
+ else if((touch3 == 0 || touch4 == 0) && (touch1 == 1 && touch2 == 1)){
+ /* Right push
+ * Success buzz */
+ readSignal = RIGHT_PUSH;
+ }
+ /* If both sides are pressed, there is an error */
+ else{
+ /* Failure buzz */
+ wait(TIME_BETWEEN_CYCLE);
+ }
+}
+
+/* Three out of four of the switches need to be touched in the correct order */
+void swiped_right(){
+ /* Assign bool variable that turns true if no error: if true, then there is a swipe */
+ bool checkSwipe = false;
+ /* Variables used for polling */
+ int i, j;
+ /* If the leftmost switch is touched, check if the next one is touched */
+ if(touch1 == 0){
+ /* If both left switches are touched, only one of the right switches need to be touched */
+ if(touch2 == 0){
+ /* Variables i and j are used for polling in a while loop 5 times to search for a touch
+ * If the required input is sensed it exits the while loop to sense the next input or make checkSwipe true
+ * Every time there is no input i or j increments
+ * If no input is sensed and i = 5 or j = 5, then it exits the while loop to keep checkSwipe false */
+ i = 5;
+ while(i > 0){
+ wait(TIME_BETWEEN_TOUCH);
+ /* If one of the right switches are touched next, then checkSwipe is true */
+ if(touch3 == 0 || touch4 == 0){
+ checkSwipe = true;
+ i = 0;
+ }
+ else{
+ i--;
+ }
+ }
+ }
+ else{
+ i = 5;
+ while(i > 0){
+ wait(TIME_BETWEEN_TOUCH);
+ /* If only the leftmost switch is touched, check if the other left switch is touched */
+ if(touch2 == 0){
+ j = 5;
+ while(j > 0){
+ wait(TIME_BETWEEN_TOUCH);
+ /* If both left switches are touched, only one of the right switches need to be touched for checkSwipe to be true */
+ if(touch3 == 0 || touch4 == 0){
+ checkSwipe = true;
+ j = 0;
+ }
+ else{
+ j--;
+ }
+ }
+ i = 0;
+ }
+ /* If the leftmost switch is touched and the third switch after, only the rightmost switch needs to be touched */
+ else if(touch3 == 0){
+ j = 5;
+ while(j > 0){
+ wait(TIME_BETWEEN_TOUCH);
+ /* If the rightmost switch is touched, checkSwipe becomes true */
+ if(touch4 == 0){
+ checkSwipe = true;
+ j = 0;
+ }
+ else{
+ j--;
+ }
+ }
+ }
+ else{
+ i--;
+ }
+ }
+ }
+ }
+ /* If only the second switchs is touched, the two right switches need to be touched */
+ else{
+ i = 5;
+ while(i > 0){
+ wait(TIME_BETWEEN_TOUCH);
+ /* If the third switch is touched, check if the rightmost switch is touched */
+ if(touch3 == 0){
+ j = 5;
+ while(j > 5){
+ wait(TIME_BETWEEN_TOUCH);
+ /* If the rightmost switch is touched, checkSwipe becomes true */
+ if(touch4 == 0){
+ checkSwipe = true;
+ j = 0;
+ }
+ else{
+ j--;
+ }
+ }
+ i = 0;
+ }
+ else{
+ i--;
+ }
+ }
+ }
+ /* If checkSwipe is true, then there was a swipe gesture */
+ if(checkSwipe){
+ /* Right swipe
+ * Success buzz */
+ readSignal = RIGHT_SWIPE;
+ }
+ /* If checkswipe is false, then there was an error */
+ else{
+ /* Failure buzz */
+ wait(TIME_BETWEEN_CYCLE);
+ }
+}
+
+/* Three out of four of the switches need to be touched in the correct order
+ * Same as swiped_right except in opposite direction */
+void swiped_left(){
+ bool checkSwipe = false;
+ int i, j;
+ if(touch4 == 0){
+ if(touch3 == 0){
+ i = 5;
+ while(i > 0){
+ wait(TIME_BETWEEN_TOUCH);
+ if(touch2 == 0 || touch1 == 0){
+ checkSwipe = true;
+ i = 0;
+ }
+ else{
+ i--;
+ }
+ }
+ }
+ else{
+ i = 5;
+ while(i > 0){
+ wait(TIME_BETWEEN_TOUCH);
+ if(touch3 == 0){
+ j = 5;
+ while(j > 0){
+ wait(TIME_BETWEEN_TOUCH);
+ if(touch2 == 0 || touch1 == 0){
+ checkSwipe = true;
+ j = 0;
+ }
+ else{
+ j--;
+ }
+ }
+ i = 0;
+ }
+ else if(touch2 == 0){
+ j = 5;
+ while(j > 0){
+ wait(TIME_BETWEEN_TOUCH);
+ if(touch1 == 0){
+ checkSwipe = true;
+ j = 0;
+ }
+ else{
+ j--;
+ }
+ }
+ }
+ else{
+ i--;
+ }
+ }
+ }
+ }
+ else{
+ i = 5;
+ while(i > 0){
+ wait(TIME_BETWEEN_TOUCH);
+ if(touch2 == 0){
+ j = 5;
+ while(j > 5){
+ wait(TIME_BETWEEN_TOUCH);
+ if(touch1 == 0){
+ checkSwipe = true;
+ j = 0;
+ }
+ else{
+ j--;
+ }
+ }
+ i = 0;
+ }
+ else{
+ i--;
+ }
+ }
+ }
+ if(checkSwipe){
+ /* Left swipe
+ * Success buzz */
+ readSignal = LEFT_SWIPE;
+ }
+ else{
+ /* Failure buzz */
+ wait(TIME_BETWEEN_CYCLE);
+ }
+}
+
+/* Main loop */
+int main(){
+ /* Setup of recurring interrupt to look for inputs every 0.3 seconds */
+ Ticker ticker;
+ ticker.attach(periodicCallback, 0.3);
+
+ /* Initialise BLE */
BLE& ble = BLE::Instance(BLE::DEFAULT_INSTANCE);
ble.init(bleInitComplete);
/* SpinWait for initialization to complete. This is necessary because the
* BLE object is used in the main loop below. */
- while (ble.hasInitialized() == false) { /* spin loop */ }
+ while(ble.hasInitialized() == false){/* Spin loop */}
/* Infinite loop waiting for BLE interrupt events */
- while (true) {
- ble.waitForEvent(); /* Save power */
+ while(1){
+ /* Check for trigger from periodicCallback() */
+ if(triggerSensorPolling && ble.getGapState().connected){
+ triggerSensorPolling = false;
+ /* Check if touch pad is pressed beyond threshold for pressing gesture */
+ if(press > THRESHOLD_PRESS){
+ pressed();
+ }
+ /* Check if touch pad is touched on one side for swiping gesture
+ * A touch on the left side would potentially be a right swipe */
+ else if((touch1 == 0 || touch2 == 0) && (touch3 == 1 && touch4 == 1)){
+ swiped_right();
+ }
+ /* A touch on the right side would potentially be a left swipe */
+ else if((touch4 == 0 || touch3 == 0) && (touch2 == 1 && touch1 == 1)){
+ swiped_left();
+ }
+ /* Input is not sent via Bluetooth if 0
+ * If not 0, send and reset to 0 for next input cycle */
+ if(readSignal != 0){
+ ble.updateCharacteristicValue(readChar.getValueHandle(), &readSignal, 1);
+ readSignal = 0;
+ wait(TIME_BETWEEN_CYCLE);
+ }
+ }
+ else{
+ ble.waitForEvent(); /* Low power wait for event */
+ }
}
}
\ No newline at end of file