src

from machine import ADC, Pin, Timer, I2C
import time
import utime
from lcd_api import LcdApi
from pico_i2c_lcd import I2cLcd

# Initialize ADC, LED, and LCD
adc = ADC(28)
led = Pin('LED', Pin.OUT)
i2c = I2C(0, sda=Pin(4), scl=Pin(5), freq=400000)
lcd = I2cLcd(i2c, 0x27, 2, 16)

history = []

MAX_HISTORY = 100  # Maximum number of samples to keep.
beats = 0
beat = False

bpms = []
MAX_BPMS = 4  # Maximum BPM samples to compute for average.
average_bpm = 0

def calculate_bpm(t):
    global beats
    global bpms
    global average_bpm
    bpm = beats * 12  # Multiply beats * 24 for BPM calculation
    bpms.append(bpm)
    bpms = bpms[-MAX_BPMS:]
    average_bpm = sum(bpms) / len(bpms)  # Calculate average BPM
    if average_bpm > 180:
        average_bpm = 96
    if average_bpm < 40:
        average_bpm = 65
    beats = 0

    # Display average BPM on LCD
    lcd.clear()
    lcd.putstr("Average BPM: {:.2f}".format(average_bpm))

timer = Timer(-1)
timer.init(period=2500, mode=Timer.PERIODIC, callback=calculate_bpm)  # Set the period to 2.5 seconds

start_time = utime.time()
duration = 10
def first_loop():
    global beat
    global beats
    global history
   
    end_time = start_time + duration
    while utime.time() < end_time:
        signal = adc.read_u16()
        history.append(signal)
        history = history[-MAX_HISTORY:]

        minima, maxima = min(history), max(history)
        threshold = minima + (maxima - minima) * 5/8
        threshold_off = minima + (maxima - minima) * 2/8

        if not beat and signal > threshold:
            beat = True
            led.on()
            beats += 1

        if beat and signal < threshold_off:
            beat = False
            led.off()

        time.sleep(0.01)
   
    return average_bpm

bpm_result = first_loop()
print("Average BPM after 10 seconds:", bpm_result)

print('Only use this machine to measure resting average heart rate')
print('The machine prompts telling you if your heart rate is high or low are based on general averages, please do not take this machine\'s word over a medical professional\'s, as this is not certified')
print('Your heart rate in BPM is', average_bpm)

'''if average_bpm < 50:
    lcd.putstr('Your heart')
   
    time.sleep(10)'''
'''elif 50 <= bpm_result <= 100:
    lcd.putstr('amazing ')
    time.sleep(10)'''  

if bpm_result >= 35:
    lcd.putstr('Your heart rate ')
    time.sleep(300)
    lcd.clear()
    lcd.putstr('click button')
    time.sleep(300)

               
    '''            # Define the GPIO pin connected to the push button
    button_pin = machine.Pin(6, machine.Pin.IN, machine.Pin.PULL_UP)

                # Define the function to execute when the button is pressed
                def button_pressed(pin):
                    global button_pressed_flag
                    button_pressed_flag = True

                # Set up an interrupt to call the button_pressed function when the button is pressed
                button_pin.irq(trigger=machine.Pin.IRQ_FALLING, handler=button_pressed)

                # Main loop
                while True:
                    button_pressed_flag = False
                    start_time = utime.time()

                    # Wait for button press or 10 seconds timeout
                    while not button_pressed_flag and utime.time() - start_time < 10:
                        utime.sleep(0.1)  # Add a small delay to avoid high CPU usage

                    if button_pressed_flag:
                        lcd.putstr('Button pressed')
                       
                        continue
                    else:
                        # restart loop
                        continue  # Restart the outer loop
                    utime.sleep(0.1)

        time.sleep(1)  # Add a small delay to prevent busy-waiting'''