Skills Dev V - Networking
Made by jmadala, Gabriela Suazo and Rachel Arre
Made by jmadala, Gabriela Suazo and Rachel Arre
We will be developing paired devices and networked interactions using Particle.publish. The devices will have a tilt sensor and a vibration motor. When the tilt sensor is tilted, the other device will vibrate.
Created: December 19th, 2020
Our goal was to pair a tilt sensor with a vibration motor to see if the tilt could start the vibration motor once tilted more than 30 degrees and then stop once it was back upright. We made this connection as part of our exploration work to see which two components were "sturdiest" and reliable in generating a notification on another device.
int tiltPin = D3;
int motorPin = D2;
void setup()
{
pinMode( tiltPin , INPUT_PULLUP );
pinMode(motorPin, OUTPUT);
}
void loop()
{
int tiltState = digitalRead( tiltPin );
int speed = 100;
if( tiltState == HIGH ) {
for( int i = 0; i < 20; i++ ){
analogWrite(motorPin, speed);
delay(1000);
}
} else {
analogWrite(motorPin, 0);
delay(1000);
}
}
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int motorPin = D2;
int tiltPin = D3;
// This value will store the last time we published an event
long lastPublishedAt = 0;
// this is the time delay before we should publish a new event
// from this device
int publishAfter = 1000;
bool motorTriggeredByOtherDevice = false;
void setup()
{
// setup the tilt switch
pinMode( tiltPin , INPUT_PULLUP );
pinMode(motorPin, OUTPUT);
// We'll want to subscribe to an event thats fairly unique
// From the Particle Docs
// A subscription works like a prefix filter.
// If you subscribe to "foo", you will receive any event
// whose name begins with "foo", including "foo", "fool",
// "foobar", and "food/indian/sweet-curry-beans".
// Basically this will match any event that starts with 'db2018/paired/'
// This is a feature we'll useto figure out if our event comes from
// this device or another (see publishMyEvent below)
Particle.subscribe( "teampotato/" , handleSharedEvent );
}
int lastTiltState = LOW;
void loop()
{
// publish my event
// you'll want some more complex stuff here
int tiltState = digitalRead( tiltPin );
int speed = 250;
if( lastTiltState != tiltState ){
publishMyEvent();
}
lastTiltState = tiltState;
if( motorTriggeredByOtherDevice ){
for( int i = 0; i < 3 ; i++ ){
analogWrite(motorPin, speed);
}
delay( 2000);
analogWrite(motorPin, 0);
motorTriggeredByOtherDevice = false;
}
// delay for a bit
delay(100);
}
void publishMyEvent()
{
// Remember that a device can publish at rate of about 1 event/sec,
// with bursts of up to 4 allowed in 1 second.
// Back to back burst of 4 messages will take 4 seconds to recover.
// So we want to limit the amount of publish events that happen.
// check that it's been 10 secondds since our last publish
if( lastPublishedAt + publishAfter < millis() )
{
// Remember our subscribe is matching "db2018/paired/"
// We'll append the device id to get more specific
// about where the event came from
// System.deviceID() provides an easy way to extract the device
// ID of your device. It returns a String object of the device ID,
// which is used to identify your device.
String eventName = "teampotato/" + System.deviceID();
// now we have something like "diot/2019/paired/0123456789abcdef"
// and that corresponds to this devices info
// then we share it out
Particle.publish( eventName, "data goes here" );
// And this will get shared out to all devices using this code
// we just pubished so capture this.
lastPublishedAt = millis();
}
}
// Our event handlde requires two bits of information
// This gives us:
// A character array that consists of the event name
// A character array that contains the data published in the event we're responding to.
void handleSharedEvent(const char *event, const char *data)
{
// Now we're getting ALL events published using "db2018/paired/"
// This includes events from this device.
// So we need to ignore any events that we sent.
// Let's check the event name
String eventName = String( event ); // convert to a string object
// This gives us access to a bunch of built in methods
// Like indexOf()
// Locates a character or String within another String.
// By default, searches from the beginning of the String,
// but can also start from a given index,
// allowing for the locating of all instances of the character or String.
// It Returns: The index of val within the String, or -1 if not found.
// We can use this to check if our event name contains the
// id of this device
String deviceID = System.deviceID();
// device id = 0123456789abcdef
// event = "diot/2019/paired/0123456789abcdef"
if( eventName.indexOf( deviceID ) != -1 ){
// if we get anything other than -1
// the event came from this device.
// so stop doing stuff
return;
}
// otherwise do your stuff to respond to
// the paired device here
motorTriggeredByOtherDevice = true;
}
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