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Language of Love
// Creation and computation Expriment 4
// Rana Zandi
// November 2016
#include <Ticker.h>
#include "config.h"
Ticker flipper;
Ticker sender;
AdafruitIO_Feed *bpm = io.feed("TK2");
const int maxAvgSample = 20;
volatile int rate[maxAvgSample]; // used to hold last ten IBI values
boolean sendok = false;
volatile unsigned long sampleCounter = 0; // used to determine pulse timing
volatile unsigned long lastBeatTime = 0; // used to find the inter beat interval
volatile int P = 250; // used to find peak in pulse wave
volatile int T = 250; // used to find trough in pulse wave
volatile int thresh = 250; // used to find instant moment of heart beat
volatile int amp = 100; // used to hold amplitude of pulse waveform
volatile boolean firstBeat = true; // used to seed rate array so we startup with reasonable BPM
volatile boolean secondBeat = true; // used to seed rate array so we startup with reasonable BPM
volatile int BPM; // used to hold the pulse rate
volatile int Signal; // holds the incoming raw data
volatile int IBI = 600; // holds the time between beats, the Inter-Beat Interval
volatile boolean Pulse = false; // true when pulse wave is high, false when it's low
volatile boolean QS = false;
int bpmSample = 3;
int bpmCurrent = 0;
int bpmAverage = 0;
void setup() {
Serial.begin(115200);
delay(10);
Serial.print("Connecting to Adafruit IO");
// connect to io.adafruit.com
io.connect();
// wait for a connection
while (io.status() < AIO_CONNECTED) {
Serial.print(".");
delay(500);
}
// we are connected
Serial.println();
Serial.println(io.statusText());
flipper.attach_ms(2, Test);
sender.attach(2, senderfunc);
}
void senderfunc()
{
sendok = true;
}
void loop() {
io.run();
if (sendok)
{
delay(100);
Serial.println(BPM);
bpmAverage += BPM;
if( bpmCurrent == bpmSample){
Serial.print("Sending Average :");
Serial.println(bpmAverage/3);
bpm->save(bpmAverage/3);
bpmAverage = 0;
bpmCurrent = 0;
}
bpmCurrent++;
delay(10);
sendok = false;
flipper.attach_ms(2, Test);
}
}
void sendBMP()
{
}
int count = 0;
void Test()
{
count++;
if (count == 1000)
{
flipper.detach();
count = 0;
sendBMP();
sendok = true;
}
Signal = analogRead(A0); // read the Pulse Sensor
sampleCounter += 2; // keep track of the time in mS with this variable
int N = sampleCounter - lastBeatTime; // monitor the time since the last beat to avoid noise
if (Signal < thresh && N > (IBI / 5) * 3) { // avoid dichrotic noise by waiting 3/5 of last IBI
if (Signal < T) { // T is the trough
T = Signal; // keep track of lowest point in pulse wave
}
}
if (Signal > thresh && Signal > P) { // thresh condition helps avoid noise
P = Signal; // P is the peak
} // keep track of highest point in pulse wave
// NOW IT'S TIME TO LOOK FOR THE HEART BEAT
// signal surges up in value every time there is a pulse
if (N > 250) { // avoid high frequency noise
if ( (Signal > thresh) && (Pulse == false) && (N > (IBI / 5) * 3) ) {
Pulse = true; // set the Pulse flag when we think there is a pulse
//digitalWrite(blinkPin,HIGH); // turn on pin 13 LED
IBI = sampleCounter - lastBeatTime; // measure time between beats in mS
lastBeatTime = sampleCounter; // keep track of time for next pulse
if (firstBeat) { // if it's the first time we found a beat, if firstBeat == TRUE
firstBeat = false; // clear firstBeat flag
return; // IBI value is unreliable so discard it
}
if (secondBeat) { // if this is the second beat, if secondBeat == TRUE
secondBeat = false; // clear secondBeat flag
for (int i = 0; i <= maxAvgSample - 1; i++) { // seed the running total to get a realisitic BPM at startup
rate[i] = IBI;
}
}
// keep a running total of the last 10 IBI values
word runningTotal = 0; // clear the runningTotal variable
for (int i = 0; i <= (maxAvgSample - 2); i++) { // shift data in the rate array
rate[i] = rate[i + 1]; // and drop the oldest IBI value
runningTotal += rate[i]; // add up the 9 oldest IBI values
}
rate[maxAvgSample - 1] = IBI; // add the latest IBI to the rate array
runningTotal += rate[maxAvgSample - 1]; // add the latest IBI to runningTotal
runningTotal /= maxAvgSample; // average the last 10 IBI values
BPM = 60000 / runningTotal; // how many beats can fit into a minute? that's BPM!
QS = true; // set Quantified Self flag
// QS FLAG IS NOT CLEARED INSIDE THIS ISR
}
}
if (Signal < thresh && Pulse == true) { // when the values are going down, the beat is over
//digitalWrite(blinkPin,LOW); // turn off pin 13 LED
Pulse = false; // reset the Pulse flag so we can do it again
amp = P - T; // get amplitude of the pulse wave
thresh = amp / 2 + T; // set thresh at 50% of the amplitude
P = thresh; // reset these for next time
T = thresh;
}
if (N > 2500) { // if 2.5 seconds go by without a beat
thresh = 250; // set thresh default
P = 250; // set P default
T = 250; // set T default
lastBeatTime = sampleCounter; // bring the lastBeatTime up to date
firstBeat = true; // set these to avoid noise
secondBeat = true; // when we get the heartbeat back
}
//sei(); // enable interrupts when youre done!
}// end isr
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