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Exit loop with KeyboardInterrupt then begin another loop in python

I currently have a piece of code designed to communicate with two motors via a TCP Device Server which sends ASCII commands to them in order to trace sinusoidal paths. I wish to have the movement continue indefinitely and then immediately stop when KeyboardInterrupt is triggered, then have the motors move back to their defined home positions before the program ends.
This code can currently replicate sinusodial motion, but it currently does not stop immediately when KeyboardInterrupt is triggered, nor do the motors move back to their home positions. The sinusodial loop is designed such that when KeyboardInterrupt occurs, a global variable called move changes from True to False and this breaks the loop. The simplified code is given below:
import socket
import time
import numpy as np
import math
pi = math.pi
try:
s1 = socket.socket(socket.AF_INET, socket.SOCK_STREAM) #TCP Server Connection
s2 = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
except:
print("Failed to connect")
exit()
print("Sockets Created")
s1.connect(("192.168.177.200", 4001)) # Y motor
s2.connect(("192.168.177.200", 4002)) # X motor
# Disengage the motor to allow manual movement by wheel
s1.send("DI\n".encode("ASCII"))
message = s1.recv(1024).decode()
s2.send("DI\n".encode("ASCII"))
message = s1.recv(1024).decode()
homeposition = input("Are the motors centred? Press 'y' to confirm: ")
if homeposition == 'y':
s1.send("EN\n".encode("ASCII"))
s2.send("EN\n".encode("ASCII")) # energise the motors so they cannot be moved
print("Motors Engaged")
s1.send("HO\n".encode("ASCII")) # set current position as home position
s2.send("HO\n".encode("ASCII")) # set current position as home position
else:
print("Set home position and restart program")
exit()
#----ADD DATA FOR SAMPLING SINUSODIAL FUNCTIONS----
radius = input("Desired radius of movement (mm):")
radius = float(radius)
print("radius of circular path (mm): ", radius)
# need slightly different ratios for each motor due to different thread sizes
gearpositionlim_x = 20000 #one rotation equals 2.5mm (+ bearing ration on manipulator of 2:1)
gearpositionlim_y = 10000 #one rotation equals 2mm
# sample sine and cosine
step = 2*pi / 1000
time_range = np.arange(0,2*pi + step,step)
x_motorrange = gearpositionlim_x*np.cos(time_range)
y_motorrange = gearpositionlim_y*np.sin(time_range)
x_motorrange = ['la'+str(int(i)) for i in x_motorrange]
y_motorrange = ['la'+str(int(i)) for i in y_motorrange]
#print(x_motorrange)
x_motorrange_wcom = []
y_motorrange_wcom = []
{x_motorrange_wcom.extend([e, 'm', 'np']) for e in x_motorrange} # add movement prompts and wait for movement to complete
{y_motorrange_wcom.extend([e, 'm', 'np']) for e in y_motorrange} # add movement prompts and wait for movement to complete
# Set Acceleration and Deceleration of Motors
s1.send("AC10\n".encode("ASCII"))
message = s1.recv(1024).decode()
s2.send("AC10\n".encode("ASCII"))
message = s2.recv(1024).decode()
print("Acceleration set to 10 ")
s1.send("DEC10\n".encode("ASCII"))
message = s1.recv(1024).decode()
s2.send("DEC10\n".encode("ASCII"))
message = s2.recv(1024).decode()
print("Deceleration set to 10")
def setup(): #move to initial position before starting movement
s2.send(str(str(x_motorrange_wcom[0])+"\n").encode("ASCII"))
s2.send("m\n".encode("ASCII"))
s2.send("np\n".encode("ASCII"))
s2.send("delay200\n".encode("ASCII"))
def end():
print("Movement ended, return to home position")
s1.send("la0\n".encode("ASCII"))
s1.send("m\n".encode("ASCII"))
s1.send("np\n".encode("ASCII"))
s1.send("delay200\n".encode("ASCII"))
s1.send("DI\n".encode("ASCII"))
s1.send("delay200\n".encode("ASCII"))
time.sleep(2)
s2.send("la0\n".encode("ASCII"))
s2.send("m\n".encode("ASCII"))
s2.send("np\n".encode("ASCII"))
s2.send("delay200\n".encode("ASCII"))
s2.send("DI\n".encode("ASCII"))
s2.send("delay200\n".encode("ASCII"))
def motormove():
global move
try:
for i in np.arange(0,len(x_motorrange)):
if (move == True):
s1.send(str(str(x_motorrange[i])+"\n").encode("ASCII"))
s2.send(str(str(y_motorrange[i])+"\n").encode("ASCII"))
else:
break
except KeyboardInterrupt:
move = False
print(move)
end()
#-------------------------------------------
setup()
name = input("Code Ready, press enter to proceed: ")
if name == "":
print("Code Running: Press ctrl + c to end")
while (move == True):
motormove()
I believe my issue is with my function motormove(), but I am unsure of what I should do in order to achieve my desired operation. Does anyone know how this can be achieved?
Thanks in advance

Using library signal should be sufficient for your usecase. See code bellow.
import socket
import signal
import time
import numpy as np
import math
pi = math.pi
try:
s1 = socket.socket(socket.AF_INET, socket.SOCK_STREAM) #TCP Server Connection
s2 = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
except:
print("Failed to connect")
exit()
print("Sockets Created")
s1.send("HO\n".encode("ASCII")) # set current position as home position
s2.send("HO\n".encode("ASCII")) # set current position as home position
gearpositionlim = int(10000)
# sample sine and cosine
step = 2*pi / 2000
time_range = np.arange(0,2*pi + step,step)
x_motorrange = gearpositionlim*np.sin(time_range)
y_motorrange = gearpositionlim*np.cos(time_range)
def handler(signum, frame):
res = input("Ctrl-c was pressed. Do you really want to exit? y/n ")
if res == 'y':
exit(1)
else:
#Do STH
def setup():
s2.send(y_motorrange[0])+"\n").encode("ASCII"))
s2.send("m\n".encode("ASCII"))
s2.send("np\n".encode("ASCII"))
s2.send("delay200\n".encode("ASCII"))
def end():
print("Movement ended, return to home position")
s1.send("la0\n".encode("ASCII"))
s1.send("m\n".encode("ASCII"))
s1.send("np\n".encode("ASCII"))
s1.send("delay200\n".encode("ASCII"))
s1.send("DI\n".encode("ASCII"))
s1.send("delay200\n".encode("ASCII"))
time.sleep(2)
s2.send("la0\n".encode("ASCII"))
s2.send("m\n".encode("ASCII"))
s2.send("np\n".encode("ASCII"))
s2.send("delay200\n".encode("ASCII"))
s2.send("DI\n".encode("ASCII"))
s2.send("delay200\n".encode("ASCII"))
def motormove():
global move
try:
for i in np.arange(0,len(x_motorrange)):
if (move == True):
s1.send(str(str(x_motorrange[i])+"\n").encode("ASCII"))
s2.send(str(str(y_motorrange[i])+"\n").encode("ASCII"))
else:
break
except KeyboardInterrupt:
signal.signal(signal.SIGINT, handler)
#-------------------------------------------
setup()
name = input("Code Ready, press enter to proceed: ")
if name == "":
print("Code Running: Press ctrl + c to end")
while (move == True):
motormove()
This should be working just fine, note the signal function being called on KeyboardInterrupt, this redirects to signal function where, you can either exit or do something else.

How to stop 'enter spamming' in a python reaction timer

I have been trying to make a reaction timer for a project to test reaction times. It uses 'perf_counter' to record the times before and after an input to test how long it takes to press the enter key. The issue is that the enter key can be spammed which makes it seem if they have a reaction time of 0.000001 seconds. I have made a class which disables the keyboard and enables it when I want. Even in that case, people are able to sneak in extra enter presses between the disables and enables. I have attached the code below. Any ideas how to prevent enter spamming?
import time, random, msvcrt
from math import log10, floor
def round_sig(x, sig=5):
return round(x, sig-int(floor(log10(abs(x))))-1)
class keyboardDisable():
def start(self):
self.on = True
def stop(self):
self.on = False
def __call__(self):
while self.on:
msvcrt.getwch()
def __init__(self):
self.on = False
import msvcrt
disable = keyboardDisable()
disable.start()
print('When I say __GO__ you hit ENTER! This will happen 3 times. Got it?')
time.sleep(2)
print('Ready')
time.sleep(1)
print('Steady')
time.sleep(random.randint(2,5))
print('#####__GO__######')
disable.stop()
tic = time.perf_counter()
a = input()
toc = time.perf_counter()
if msvcrt.kbhit():
disable.start()
timeSpent = toc-tic
print('Your first time was '+str(timeSpent) + ' seconds')
time.sleep(1)
print('The next one is coming up.')
time.sleep(1)
print('Ready')
time.sleep(1)
print('Steady')
time.sleep(random.randint(2,5))
print('#####__GO__######')
disable.stop()
tic2 = time.perf_counter()
b = input()
toc2 = time.perf_counter()
if msvcrt.kbhit():
disable.start()
timeSpent2 = toc2-tic2
print('Your second time was '+str(timeSpent2) + ' seconds')
time.sleep(1)
print('The last one is coming up.')
time.sleep(1)
print('Ready')
time.sleep(1)
print('Steady')
time.sleep(random.randint(2,5))
print('#####__GO__######')
disable.stop()
tic3 = time.perf_counter()
c = input()
toc3 = time.perf_counter()
timeSpent3 = toc3-tic3
print('Your last time was '+str(timeSpent3) + ' seconds')
average = (timeSpent + timeSpent2 + timeSpent3)/3
numAverage = round_sig(average)
print('Your average time is '+str(numAverage) + ' seconds')

The keyboard-disabling code never really runs.
Here's a simplification of your program that uses a function to capture one reaction time and calls it thrice.
The clear_keyboard_buffer() function (that should consume all outstanding keystrokes) was borrowed from https://stackoverflow.com/a/2521054/51685 .
import time, random, msvcrt, math
def round_sig(x, sig=5):
return round(x, sig - int(math.floor(math.log10(abs(x)))) - 1)
def clear_keyboard_buffer():
while msvcrt.kbhit():
msvcrt.getwch()
def get_reaction_time():
print("Ready")
time.sleep(1)
print("Steady")
time.sleep(random.randint(2, 5))
print("#####__GO__######")
clear_keyboard_buffer()
tic = time.perf_counter()
a = input()
toc = time.perf_counter()
return toc - tic
print("When I say __GO__ you hit ENTER! This will happen 3 times. Got it?")
time1 = get_reaction_time()
print(f"Your first time was {time1} seconds")
time.sleep(1)
print("The next one is coming up.")
time2 = get_reaction_time()
print(f"Your first time was {time2} seconds")
time.sleep(1)
print("The last one is coming up.")
time3 = get_reaction_time()
print(f"Your first time was {time3} seconds")
average = (time1 + time2 + time3) / 3
print(f"Your average time is {round_sig(average)} seconds")

This solution uses a Thread to start the timer, while the main thread waits for input all the time. That way, it is possible to catch early key presses:
from threading import Thread
import random
import time
def start():
global started
started = None
time.sleep(random.randint(2,5))
print("#### GO ####")
started = time.time()
t = Thread(target=start)
print("ready...")
# start the thread and directly wait for input:
t.start()
input()
end = time.time()
if not started:
print("Fail")
else:
print(end-started)
t.join()

Counter in Python for Rising Edges

Dear Stackoverflow Community!
I am currently on my first Project working with a Raspberry Pi. The task is to implement a TY-010 Photo Interruptor Sensor. What I want to do is following:
I want to count the interruptions in a given time (i.e 2 seconds). So something like that(not C, in Python):
d count how many Interruptions there are.
int i = 0
while(time != 3){
if(outputFunction == True)
i += 1;
}
You can find the whole Code beneath:
import RPi.GPIO as GPIO
import time
GPIO_PIN = 24
GPIO.setup(GPIO_PIN, GPIO.IN, pull_up_down = GPIO.PUD_DOWN)
print "Sensor-Test [Press STRG+C, to exit the Test]"
def outputFunction(null):
print("Signal detected")
GPIO.add_event_detect(GPIO_PIN, GPIO.RISING, callback=ausgabeFunktion, bouncetime=100)
try:
while True:
time.sleep(1)
except KeyboardInterrupt:
GPIO.cleanup()
I am thankful for any help or advise !

You have wrong defined ouputFunction, if you want a function without arguments just leave it empty, like this:
def outputFunction():
print("Signal detected")
You can add a statement to verify if have passed x seconds, if you do time.sleep() you are stopping your code and if you press the button it won't work, so do it this way:
try:
t_to_wait = 2 #Set to 2 secs
t1 = time.time() #Get the start time
while True:
if GPIO.input(GPIO_PIN) == 1:
outputFunction()
if t1-time.time() > t_to_wait:
break #Exit the loop if have passed t_to_wait seconds
except KeyboardInterrupt:
GPIO.cleanup()
I also would recommend you to read some examples because it seems that you don't know python very well and the use of the GPIO module

How do I run two while True statements in python?

I am trying to make a door swipe card system in Python for my Raspberry Pi. I broke the program into two: A Door Alarm and a Card Swipe Recording system. The two programs work individually but how do I combine the two programs into one python file? I've tried threading but it doesn't seem to work.
Below are the programs:
1.) Door Alarm: If door is left open for a certain duration, an led will blink, then an alarm will ring
import time
import RPi.GPIO as gpio
led = 37
buzzer = 11
door = 16
gpio.setmode(gpio.BOARD)
gpio.setwarnings(False)
gpio.setup(buzzer, gpio.OUT)
gpio.setup(led, gpio.OUT)
gpio.setup(door, gpio.IN, pull_up_down=gpio.PUD_UP)
def blink(buzzer):
gpio.output(buzzer, True)
time.sleep(0.1)
gpio.output(buzzer, False)
time.sleep(0.1)
return
def blink(led):
gpio.output(led, True)
time.sleep(1)
gpio.output(led, False)
time.sleep(1)
return
while True:
if gpio.input(door):
time.sleep(3)
for i in range(0,5):
blink(led)
for i in range (0,5):
blink(buzzer)
else:
gpio.output(buzzer, False)
gpio.cleanup()
2.) Card Swipe Recording System: When someone swipes their card, the led blinks and a picture is taken
import datetime
import time
import os
import RPi.GPIO as gpio
led = 37
t = datetime.datetime.now()
gpio.setmode(gpio.BOARD)
gpio.setwarnings(False)
gpio.setup(led, gpio.OUT)
def blink(led):
gpio.output(led, True)
time.sleep(0.1)
gpio.output(led, False)
time.sleep(0.1)
while True:
card = raw_input()
f = open("Laptop Sign Out" + '.txt', 'a')
f.write("OneCard Number: " + card[1:10] + " Time: " + t.strftime("%m-%d-%Y %H:%M:%S"))
f.write('\n')
f.write(';')
f.write('\n')
f.close()
time.sleep(1)
for i in range(0,3):
blink(led)
os.system('fswebcam ~/Desktop/Photos/%H%M%S.jpeg')
time.sleep(3)
gpio.cleanup()
(UPDATE) Also, below is my attempt at threading:
import time
import RPi.GPIO as gpio
import os
import datetime
from threading import Thread
led = 37
buzzer = 11
door = 16
t = datetime.datetime.now()
gpio.setmode(gpio.BOARD)
gpio.setwarnings(False)
gpio.setup(buzzer, gpio.OUT)
gpio.setup(led, gpio.OUT)
gpio.setup(door, gpio.IN, pull_up_down=gpio.PUD_UP)
def blink(buzzer):
gpio.output(buzzer, True)
time.sleep(0.1)
gpio.output(buzzer, False)
time.sleep(0.1)
return
def blink(led):
gpio.output(led, True)
time.sleep(1)
gpio.output(led, False)
time.sleep(1)
return
def doorsensor():
while True:
if gpio.input(door):
time.sleep(3)
for i in range(0,5):
blink(led)
for i in range (0,5):
blink(buzzer)
else:
gpio.output(buzzer, False)
def cardreader():
while True:
card = raw_input()
f = open("Laptop Sign Out" + '.txt', 'a')
f.write("OneCard Number: " + card[1:10] + " Time: " + t.strftime("%m-%d-%Y %H:%M:%S"))
f.write('\n')
f.write(';')
f.write('\n')
f.close()
time.sleep(1)
for i in range(0,3):
blink(led)
os.system('fswebcam ~/Desktop/Photos/%H%M%S.jpeg')
time.sleep(3)
f1 = Thread(target = doorsensor())
f2 = Thread(target = cardreader())
f2.start()
f1.start()
gpio.cleanup()

You need to pass your thread functions as the target arguments, not their return values:
import sleep
f1 = Thread(target=doorsensor) # Remove parentheses after doorsensor
f1.daemon = True
f1.start()
f2 = Thread(target=cardreader) # Remove parentheses after cardreader
f2.daemon = True
f2.start()
# Use a try block to catch Ctrl+C
try:
# Use a while loop to keep the program from exiting and killing the threads
while True:
time.sleep(1.0)
except KeyboardInterrupt:
pass
gpio.cleanup()
The daemon property is set on each thread so that the program will exit when only the daemon threads are left:
A thread can be flagged as a “daemon thread”. The significance of this flag is that the entire Python program exits when only daemon threads are left. The initial value is inherited from the creating thread. The flag can be set through the daemon property.

I'm presenting a thread-less approach.
The idea is to turn your while bodies into update functions, and call them alternatively.
First off, your door loop becomes
def update_door():
if gpio.input(door):
time.sleep(3)
for i in range(0,5):
blink(led)
for i in range (0,5):
blink(buzzer)
else:
gpio.output(buzzer, False)
Then your card swipe recording system becomes
def update_card():
card = raw_input()
f = open("Laptop Sign Out" + '.txt', 'a')
f.write("OneCard Number: " + card[1:10] + " Time: " + t.strftime("%m-%d-%Y %H:%M:%S"))
f.write('\n')
f.write(';')
f.write('\n')
f.close()
time.sleep(1)
for i in range(0,3):
blink(led)
os.system('fswebcam ~/Desktop/Photos/%H%M%S.jpeg')
time.sleep(3)
Finally, your main loop becomes:
while True:
update_door()
update_card()
But a problem arises: time.sleep in update_card will delay update_door as well.
Here, you have three solutions:
1 - It's ok if update_door is delayed
Well, ok.
2 - It's not ok if update_door is delayed, but it's ok if update_card is not delayed
Then just remove time.sleep(3).
3 - You need update_door not to be delayed, and update_card to be delayed
Then you can set a manual timer, using the time module.
lastCardUpdate = time.time()
while True:
update_door()
now = time.time()
if now - lastCardUpdate >= 3:
update_card()
lastCardUpdate = now
But raw_input in update_card is a blocking method, waiting for a user input.
If you do need this user input to happen every three seconds, then this approach cannot be used.
If you can move it before the while, ie outside of the update_card function, then it's fine.
Else, you will indeed need to use threads.

If you are attempting to run these two programs simultaneously, then you will have to use either threading or multiprocessing, which you say you have attempted. If you have, may we see your attempt as we may be then able to help you with your issue there.
One other issue is that all of your methods are named Blink, which is not allowed in Python, in python all of your methods should have different names.
Edit: For threading make sure to type threading.Thread(target = target) as your code

Regardless of any other mistake, you need to join one of your threads once they have been started.
f1 = Thread(target = doorsensor())
f2 = Thread(target = cardreader())
f2.start()
f1.start()
f1.join()
What does f1.join() do?
Basically, it tells Python to wait until f1 has finished running.
If you don't do so, the program will start f1 and f2, then will exit.
Upon exiting, Python will release all the resources, including those two threads, whose execution will stop.

math quiz with a time limit (simultaneous functions) - advanced python

So I would like to run two programs, a timer and a math question. But always the input seems to be stopping the timer funtion or not even run at all. Is there any ways for it to get around that?
I'll keep the example simple.
import time
start_time = time.time()
timer=0
correct = answer
answer = input("9 + 9 = ")
#technically a math question here
#so here until i enter the input prevents computer reading the code
while True:
timer = time.time() - start_time
if timer > 3:
#3 seconds is the limit
print('Wrong!')
quit()
So recap i would like the player to answer the question in less than 3 seconds.
after the 3 seconds the game will print wrong and exit
if the player answer within three seconds the timer would be 'terminated' or stopped before it triggers 'wrong' and quit
hope you understand, and really appreciate your help

On Windows you can use the msvcrt module's kbhit and getch functions (I modernized this code example a little bit):
import sys
import time
import msvcrt
def read_input(caption, timeout=5):
start_time = time.time()
print(caption)
inpt = ''
while True:
if msvcrt.kbhit(): # Check if a key press is waiting.
# Check which key was pressed and turn it into a unicode string.
char = msvcrt.getche().decode(encoding='utf-8')
# If enter was pressed, return the inpt.
if char in ('\n', '\r'): # enter key
return inpt
# If another key was pressed, concatenate with previous chars.
elif char >= ' ': # Keys greater or equal to space key.
inpt += char
# If time is up, return the inpt.
if time.time()-start_time > timeout:
print('\nTime is up.')
return inpt
# and some examples of usage
ans = read_input('Please type a name', timeout=4)
print('The name is {}'.format(ans))
ans = read_input('Please enter a number', timeout=3)
print('The number is {}'.format(ans))
I'm not sure what exactly you have to do on other operating systems (research termios, tty, select).
Another possibility would be the curses module which has a getch function as well and you can set it to nodelay(1) (non-blocking), but for Windows you first have to download curses from Christopher Gohlke's website.
import time
import curses
def main(stdscr):
curses.noecho() # Now curses doesn't display the pressed key anymore.
stdscr.nodelay(1) # Makes the `getch` method non-blocking.
stdscr.scrollok(True) # When bottom of screen is reached scroll the window.
# We use `addstr` instead of `print`.
stdscr.addstr('Press "q" to exit...\n')
# Tuples of question and answer.
question_list = [('4 + 5 = ', '9'), ('7 - 4 = ', '3')]
question_index = 0
# Unpack the first question-answer tuple.
question, correct_answer = question_list[question_index]
stdscr.addstr(question) # Display the question.
answer = '' # Here we store the current answer of the user.
# A set of numbers to check if the user has entered a number.
# We have to convert the number strings to ordinals, because
# that's what `getch` returns.
numbers = {ord(str(n)) for n in range(10)}
start_time = time.time() # Start the timer.
while True:
timer = time.time() - start_time
inpt = stdscr.getch() # Here we get the pressed key.
if inpt == ord('q'): # 'q' quits the game.
break
if inpt in numbers:
answer += chr(inpt)
stdscr.addstr(chr(inpt), curses.A_BOLD)
if inpt in (ord('\n'), ord('\r')): # Enter pressed.
if answer == correct_answer:
stdscr.addstr('\nCorrect\n', curses.A_BOLD)
else:
stdscr.addstr('\nWrong\n', curses.A_BOLD)
if timer > 3:
stdscr.addstr('\nToo late. Next question.\n')
if timer > 3 or inpt in (ord('\n'), ord('\r')):
# Time is up or enter was pressed; reset and show next question.
answer = ''
start_time = time.time() # Reset the timer.
question_index += 1
# Keep question index in the correct range.
question_index %= len(question_list)
question, correct_answer = question_list[question_index]
stdscr.addstr(question)
# We use wrapper to start the program.
# It handles exceptions and resets the terminal after the game.
curses.wrapper(main)

Use time.time(), it returns the epoch time (that is, the number of seconds since January 1, 1970 UNIX Time). You can compare it to a start time to get the number of seconds:
start = time.time()
while time.time() - start < 60:
# stuff
You can have a timer pull you out of your code at any point (even if the user is inputting info) with signals but it is a little more complicated. One way is to use the signal library:
import signal
def timeout_handler(signal, frame):
raise Exception('Time is up!')
signal.signal(signal.SIGALRM, timeout_handler)
This defines a function that raises an exception and is called when the timeout occurs. Now you can put your while loop in a try catch block and set the timer:
signal.alarm.timeout(60)
try:
while lives > 0
# stuff
except:
# print score