from machine import Pin, ADC, I2C
from ssd1306 import SSD1306_I2C
import time

# Initialize I2C for OLED
i2c = I2C(0, scl=Pin(22), sda=Pin(21))
oled = SSD1306_I2C(128, 64, i2c)

# Initialize ADC for Pulse Sensor
pulse_sensor = ADC(Pin(34))
pulse_sensor.atten(ADC.ATTN_11DB)  # Set attenuation for wider range

# Function to read heartbeat sensor
def read_pulse():
    return pulse_sensor.read()

# Display initialization message
oled.fill(0)
oled.text("Initializing...", 0, 0)
oled.show()
time.sleep(2)

# Main loop
while True:
    heartbeat_value = read_pulse()

    # Debug: print raw sensor value to serial monitor
    print("Heartbeat:", heartbeat_value)

    # Clear the display
    oled.fill(0)

    # Display the heartbeat value
    oled.text("Heartbeat:", 0, 0)
    oled.text(str(heartbeat_value), 0, 10)

    # Update the display
    oled.show()

    # Wait before taking another reading
    time.sleep(0.5)