program2.py

# Program 2
# My design uses pin 12 as input and pin 11 as output. 
# When 0 switch off it'll blink at 2 second intervals and blink at 1 second intervals when 1.

import RPi.GPIO as GPIO  # type: ignore
import time

GPIO.setwarnings(False)
GPIO.setmode(GPIO.BOARD)

LED_PIN = 11
SWITCH_PIN = 12

GPIO.setup(LED_PIN, GPIO.OUT, initial=GPIO.LOW)
GPIO.setup(SWITCH_PIN, GPIO.IN)  # This is external 330Ω pull out

start = time.time()
led_state = False

# Open log file once in append mode
f = open("data.txt", "a")

# This 10 second loop makes the LED blink correctly.
while (time.time() - start) < 10:
    switch_state = GPIO.input(SWITCH_PIN)
    
    if switch_state == 0:
        interval = 2
        switch_str = "off"
    else:
        interval = 1
        switch_str = "on"

    led_state = not led_state
    GPIO.output(LED_PIN, led_state)

    time.sleep(interval)

    GPIO.output(LED_PIN, GPIO.LOW)  # Makes sure LED is off

    # Log in a txt file
    elapsed = time.time() - start
    elapsed_ms = round(elapsed, 3)

    f.write(f"{elapsed_ms:.3f}\t{switch_str}\n")
    f.flush()

# Close log file after loop
f.close()