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setting rpi-gpio pin on high after running a python script

I'm building a photogrametry setup with raspberry pi and stepper motor.
The python script runs fine, but i got a problem with setting a pin to high after the script ran through.
The stepper driver has an enable input, which diasables the motor with high input, so i set the pin (gpio26) on high on boot with pigpio, this works fine. While running the python script, the pin is set on low, so the stepper can proceed, after proceeding i want to set the pin on high again.
i tried following commands:
os.system('pigs w 26 1') and
subprocess.call("pigs w 26 1", shell=True)
for a moment they work, but after exiting the script the pin is set on low again.
It's like the commands are resetted after the script stops.
Where is my fault?
Thank you
Edit:
Here is the gpio related code:
import os, sys
import subprocess
from time import sleep
from gpiozero import DigitalOutputDevice as stepper
def InitGPIO():
try:
global step_pul #pulse
global step_en #enable
step_pul=stepper(21)
step_en=stepper(26)
print ("GPIO initialisiert.")
except:
print ("Fehler bei der GPIO-Initialisierung.")
def motor_step():
SPR=40000 #steps per rotation
step_count = SPR
delay = .000025
for x in range(step_count):
step_pul.on()
sleep(delay)
step_pul.off()
sleep(delay)
InitGPIO()
step_en.off()
for i in range(1):
#camTrigger(1)
motor_step()
#os.system('sudo -u root -S pigs w 26 1')
subprocess.call("pigs w 26 1", shell=True)
When i type pigs w 26 1 in the shell, it works...

To make my comment an answer:
Gpiozero only resets the pins it touches, so if you don't initialize or touch pin 26 with gpiozero (i.e. replace step_en.off() with pigs w 26 0 and don't even initialize step_en), it shouldn't also reset the pin:
import os
import time
import gpiozero
step_pul = gpiozero.DigitalOutputDevice(21)
def motor_step():
SPR = 40000 # steps per rotation
step_count = SPR
delay = .000025
for x in range(step_count):
step_pul.on()
time.sleep(delay)
step_pul.off()
time.sleep(delay)
# Enable motor
os.system("pigs w 26 0")
for i in range(1):
# camTrigger(1)
motor_step()
# Disable motor
os.system("pigs w 26 1")

Python Code for RPM-measurement with Raspberry Pi

I'm working on a project where I use a photoelectric sensor to detect a reflector attached to a motor axis. Every time the reflector reflects the light from the LED from the sensor it sends a pulse (voltage) to the raspberry pi (with a voltage divider). With some help I've come to the following code and I've noticed that the results that I'm getting are way too high. Anybody got any suggestions on how to improve it? I've seen other examples of RPM code online, but I wanted to learn it myself and the ones that I've found did not use the same method as me. Thanks in advance!
import time
from gpiozero import Button
sensor = Button(17)
i=1
timestampeven=0
timestamponeven=0
def pulsen():
global i
global timestampeven
global timestamponeven
if (i % 2) ==0:
timestampeven = time.time_ns()
i+=1
elif (i % 2) == 1:
timestamponeven = time.time_ns()
i+=1
periode = timestamponeven-timestampeven
frequentie = 1/(periode*10e09)
rpm = frequentie*60
print("rpm=" + str(rpm))
print("teller = " +str(i))
print("periode = " +str(periode))
print("frequentie = " +str(frequentie))
sensor.when_pressed = pulsen
while True:
pass

How to automate control of Wemo light switch based on iPhone GPS

I'm writing a program to toggle the lights at my house based on my iPhone's GPS coordinates. Below is what I have so far. However, I feel like there must be a better way to do this. Is there a way to get GPS data without pinging my phone every five minutes?
So far I've tried the following with no joy:
Using Shortcuts and Scriptable I tried to write some JavaScript that would trigger when I got close to home. However, I could not figure out how to use await require('wemo-client') using scriptablify. I kept getting an error, "ReferenceError: Can't find variable: require".
IFTTT does not have a variable timed trigger so the lights won't turn off after 15 minutes. Also, I plan on adding a motion sensor trigger that is unsupported.
Pythonista is $10. Yes, I am that cheap.
Apple HomeKit does not support the model I'm using, Wemo Smart Light Switch F7C030.
The code below works, but I hate that I have to ping my phone every five minutes. I'd rather save battery life by firing this code once or twice a day, as needed.
Any suggestions would be greatly appreciated.
Code:
import sys
import time
import datetime
import os
from pyicloud import PyiCloudService
import pywemo
APPLE_ID = os.getenv('APPLE_ID') # Apple ID username
APPLE_ID_PASSWORD = os.getenv('APPLE_ID_PASSWORD') # Apple ID password
API = PyiCloudService(APPLE_ID, APPLE_ID_PASSWORD)
IPHONE = API.devices[1]
LOCATION = IPHONE.location()
FIVE = 300 # 5 * 60 seconds
FIFTEEN = 900 # 15 * 60 seconds
ONEMILE = 0.01449275362318840579710144927536 # one mile is 1/69 degrees lat or long
HOMELAT = # my home's latitude
HOMELONG = # my home's longitude
WEMOS = pywemo.discover_devices()
LEN_WEMOS = range(len(WEMOS))
# Two factor authentication to retrieve iPhone data
if API.requires_2fa:
import click
print("Two-step authentication required. Your trusted devices are:")
DEVICES = API.devices
for i, device in enumerate(DEVICES):
print(" %s: %s" % (i, device.get('deviceName', "SMS to %s" % device.get('phoneNumber'))))
DEF_DEVICE = click.prompt('Which device would you like to use?', default=0)
DEVICE = DEVICES[DEF_DEVICE]
if not API.send_verification_code(DEVICE):
print("Failed to send verification code")
sys.exit(1)
CODE = click.prompt('Please enter validation code')
if not API.validate_verification_code(DEVICE, CODE):
print("Failed to verify verification code")
sys.exit(1)
# Turn off the lights when I leave
def leavehome():
timenow = datetime.datetime.now()
print("Left home on {}".format(timenow.strftime("%B %d, %Y at %H:%M:%S")))
for wemo in LEN_WEMOS:
WEMOS[wemo].off()
# Turn on the lights for 15 minutes when I get home
def arrivehome():
timenow = datetime.datetime.now()
print("Arrived home on {}".format(timenow.strftime("%B %d, %Y at %H:%M:%S")))
# Loop through all Wemo devices
for wemo in LEN_WEMOS:
WEMOS[wemo].on()
time.sleep(FIFTEEN)
for wemo in LEN_WEMOS:
WEMOS[wemo].off()
# Automatically turn off the lights after 15 minutes - save electricity
def timeoff():
time.sleep(FIFTEEN)
for wemo in LEN_WEMOS:
WEMOS[wemo].off()
# Ping my phone for GPS data
def pingphone(prev):
mylat = LOCATION["latitude"]
mylong = LOCATION["longitude"]
logic(prev, mylat, mylong)
time.sleep(FIVE)
# Perform logic to determine if I'm home, out, arriving, or leaving
def logic(prev, lat, long):
inrange = (HOMELAT+ONEMILE >= lat >= HOMELAT-ONEMILE and HOMELONG+ONEMILE >= long >= HOMELONG-ONEMILE)
current = bool(inrange)
previous = prev
if current and not previous:
arrivehome()
elif previous and not current:
leavehome()
else:
timeoff()
pingphone(current)
# Run the script
pingphone(False)

Micro Switch with pyserial RS232 starts/stops a timer in a tkinter thread but continues to run even when stopped

I have been using a micro switch connected to an RS232/USB serial converter cable on my windows PC to start stop and reset a timer.
The program runs smoothly most of the time but every so often updating the timer widget gets stuck running and the timer will not stop.
With the serial protocol i want to receive 1 byte b'\x00' for off and anything that's not b'\x00' should signify on.
I have replaced the micro switch with button widgets to simulate the switch and don't get the same error or i just have not kept at it for long enough.
It could be an issue with the RS232 causing an error i cannot see but my knowledge on this is sketchy and have exhausted all avenues looking online for any information on this.
import time
import sys
import serial
import threading
from tkinter import *
from tkinter import ttk
class Process(Frame):
def __init__(self, root, parent=None, **kw):
Frame.__init__(self, parent, kw)
self.root = root
self._cycStart = 0.0
self._cycTimeElapsed = 0.0
self._cycRunning = 0.0
self.cycTimeStr = StringVar()
self.cycTime_label_widget()
self.ser = serial.Serial(
port='COM4',
baudrate=1200,
timeout=0
)
self.t1 = threading.Thread(target=self.start_stop, name='t1')
self.t1.start()
def initUI(self):
root.focus_force()
root.title("")
root.bind('<Escape>', lambda e: root.destroy())
def cycTime_label_widget(self):
# Make the time label
cycTimeLabel = Label(root, textvariable=self.cycTimeStr, font=
("Ariel 12"))
self._cycleSetTime(self._cycTimeElapsed)
cycTimeLabel.place(x=1250, y=200)
cycTimeLabel_2 = Label(root, text="Cycle Timer:", font=("Ariel
12"))
cycTimeLabel_2.place(x=1150, y=200)
def _cycleUpdate(self):
""" Update the label with elapsed time. """
self._cycTimeElapsed = time.time() - self._cycStart
self._cycleSetTime(self._cycTimeElapsed)
self._cycTimer = self.after(50, self._cycleUpdate)
def _cycleSetTime(self, elap):
""" Set the time string to Minutes:Seconds:Hundreths """
minutes = int(elap/60)
seconds = int(elap - minutes*60.0)
hseconds = int((elap - minutes*60.0 - seconds)*100)
self.cycTimeStr.set('%02d:%02d:%02d' % (minutes, seconds,
hseconds))
return
def cycleStart(self):
""" Start the stopwatch, ignore if running. """
if not self._cycRunning:
self._cycStart = time.time() - self._cycTimeElapsed
self._cycleUpdate()
self._cycRunning = 1
else:
self.cycleReset()
def cycleStop(self):
""" Stop the stopwatch, ignore if stopped. """
if self._cycRunning:
self.after_cancel(self._cycTimer)
self._cycTimeElapsed = time.time() - self._cycStart
self._cycleSetTime(self._cycTimeElapsed)
self._cycRunning = 0
self._cycTimeElapsed = round(self._cycTimeElapsed, 1)
self.cycleTimeLabel = Label(root, text=(self._cycTimeElapsed,
"seconds"), font=("Ariel 35"))
self.cycleTimeLabel.place(x=900, y=285)
self.cycleReset()
def cycleReset(self):
""" Reset the stopwatch. """
self._cycStart = time.time()
self._cycTimeElapsed = 0
self._cycleSetTime(self._cycTimeElapsed)
def start_stop(self):
while True :
try:
data_to_read = self.ser.inWaiting()
if data_to_read != 0: # read if there is new data
data = self.ser.read(size=1).strip()
if data == bytes(b'\x00'):
self.cycleStop()
print("Off")
elif data is not bytes(b'\x00'):
self.cycleStart()
print("On")
except serial.SerialException as e:
print("Error")
if __name__ == '__main__':
root = Tk()
application = Process(root)
root.mainloop()
I expect the timer to start running when the micro switch is pressed. when depressed it should stop and reset back to zero and wait for the next press

With a better understanding of what you're trying to do better solutions come to mind.
As it turns out, you're not using your serial port to send or receive serial data. What you're actually doing is wiring a switch to its RX line and toggling it manually with a mechanical switch, feeding a high or low level depending on the position of the switch.
So what you're trying to do is emulating a digital input line with the RX line of your serial port. If you take a look a how a serial port works you'll see that when you send a byte the TX line toggles from low to high at the baud rate, but on top of the data you have to consider the start and stop bits. So, why your solution works (at least sometimes): that's easy to see when you look at a scope picture:
This is a screenshot of the TX line sending the \x00 byte, measured between pins 3 (TX) and 5 (GND) with no parity bit. As you can see the step only lasts for 7.5 ms (with a 1200 baud rate). What you are doing with your switch is something similar but ideally infinitely long (or until you toggle your switch back, which will be way after 7.5 ms no matter how fast you do it). I don't have a switch to try but if I open a terminal on my port and use a cable to shortcircuit the RX line to pin 4 (on a SUB-D9 connector) sometimes I do get a 0x00 byte, but mostly it's something else. You can try this experiment yourself with PuTTy or RealTerm and your switch, I guess you'll get better results but still not always the byte you expect because of the contacts bouncing.
Another approach: I'm sure there might be ways to improve on what you have, maybe reducing the baud rate to 300 or 150 bps, checking for a break in the line or other creative ideas.
But what you're trying to do is more akin to reading a GPIO line, and actually, the serial port has several digital lines intended (in the old days) for flow control.
To use these lines you should connect the common pole on your switch to the DSR line (pin 6 on a SUB-D9) and the NO and NC poles to lines DTR (pin 4) and RTS (pin 7).
The software side would be actually simpler than reading bytes: you just have to activate hardware flow control :
self.ser = serial.Serial()
self.ser.port='COM4'
self.ser.baudrate=1200 #Baud rate does not matter now
self.ser.timeout=0
self.ser.rtscts=True
self.ser.dsrdtr=True
self.ser.open()
Define the logical levels for your switch:
self.ser.setDTR(False) # We use DTR for low level state
self.ser.setRTS(True) # We use RTS for high level state
self.ser.open() # Open port after setting everything up, to avoid unkwnown states
And use ser.getDSR() to check the logical level of the DSR line in your loop:
def start_stop(self):
while True :
try:
switch_state = self.ser.getDSR()
if switch_state == False and self._cycRunning == True:
self.cycleStop()
print("Off")
elif switch_state == True and self._cycRunning == False:
self.cycleStart()
print("On")
except serial.SerialException as e:
print("Error")
I defined your self._cycRunning variable as boolean (in your initialization code you had defined it as float, but that was probably a typo).
This code works with no glitches at all even using a stripped wire as a switch.

You don't explain very well how your protocol works (I mean what is your switch supposed to be sending, or if it's sending a state change only once or several times or continuously).
But there are some red flags on your code anyway:
-With data = self.ser.read(size=1).strip() you read 1 byte but immediately you check if you have received 2 bytes. Is there a reason to do that?
-Your timer stop condition works comparing with the NULL character. That should not be a problem, but depending on your particular configuration it might (in some configurations the NULL character is read as something else, so it's wise to make sure you're really receiving it correctly).
-Your timer start condition seems too loose. Whatever you receive on the port, if it's one byte, you start your timer. Again, I don't know if that's the way your protocol works but it seems prone to trouble.
-When you replace your hardware switch with a software emulation it works as intended, but that is not surprising since you're probably imposing the condition. When you read from the serial port you have to deal with real world issues like noise, communication errors or the switch bouncing back and forth from ON to OFF. Maybe for a very simple protocol you don't need to use any error checking method, but it seems wise to at least check for parity errors. I'm not completely sure it would be straight-forward to do that with pyserial; on a quick glance I found this issue that's been open for a while.
-Again, the lack of info on your protocol: should you be using XON-XOFF flow control and two stop bits? I guess you have a reason to do it, but you should be very aware of why and how you're using those.
EDIT: With the comments below I can try to improve a bit my answer. This is just an idea for you to develop: instead of making the stop condition comparing exactly with 0x00 you can count the number of bits set to 1 and stop the counter if it's less or equal to 2. That way you can account for bits that are not received correctly.
You can do the same with the start condition but I don't know what hex value you send.
Credits for the bit counting function go to this question.
...
def numberOfSetBits(i):
i = i - ((i >> 1) & 0x55555555)
i = (i & 0x33333333) + ((i >> 2) & 0x33333333)
return (((i + (i >> 4) & 0xF0F0F0F) * 0x1010101) & 0xffffffff) >> 24
def start_stop(self):
while True :
try:
data_to_read = self.ser.inWaiting()
if data_to_read != 0: # read if there is new data
data = self.ser.read(size=1).strip()
if numberOfSetBits(int.from_bytes(data, "big")) <= 2:
self.cycleStop()
print("Off")
elif numberOfSetBits(int.from_bytes(data, "big")) >= 3: #change the condition here according to your protocol
self.cycleStart()
print("On")
except serial.SerialException as e:
print("Error")

Python time between x and y run code. And no code if time between xy

Im gonna try and explain to the best of my efforts.
Script im running is below.
I want to include something that will make the pir sensor not do anything between the hours of 24:00 and 05:00. But the button should work at those times regardless.
Also i want to be able to send different colors at certain times of the day.
So that if its between 8pm and 11 pm it will give this code to the lights: {"on":true,"bri":255,"sat":80,"hue":357}
There will be 4 colors in total. I have tried defining the command called with command(): and the colors but im at a standstill here.
Can anyone help me with this? I do really hope i made myself clear here, but fire away if anything is unclear.
import sys
sys.path.append("/home/pi/.local/lib/python2.7/site-packages")
from phue import Bridge
import RPi.GPIO as GPIO
import time
import datetime
print 'Waiting for network...'
time.sleep(30)
print 'The wait is over. It\'s showtime!'
GPIO.setwarnings(False)
GPIO.setmode(GPIO.BCM)
GPIO.setup(4, GPIO.IN) #Read output from PIR motion sensor
GPIO.setup(18, GPIO.IN, pull_up_down=GPIO.PUD_UP) #Read output from button.
b=Bridge('192.168.1.47')
try:
b.connect()
except ImportError:
print "Import error occurred!"
print "Connected to Hue bridge!"
lightson=b.get_light(2, "on")
if lightson: print "Lights are already on."
print 'Entering infinite loop...'
light_on_delay = 15 # time in min for light to stay on when button pressed
button_pressed = 0
while True:
# check for button press
input_state = GPIO.input(18)
if input_state == False:
print('Button Pressed')
end = (light_on_delay * 1) + time.time()
button_pressed = 1
command = {"on" : True, "bri" : 255, "sat" : 0, "hue" : 0}
b.set_group(2, command)
lightson=True
print('Lights are on for 15 minutes')
# check if button has been pressed if it has check to see if time is up
if button_pressed == 1:
if time.time() > end:
button_pressed = 0
else:
i=GPIO.input(4)
timestamp=datetime.datetime.now().time()
if (timestamp < offstarttime and timestamp > offendtime):
if i==0: #When output from motion sensor is LOW
print ('No movement detected - Turning lights off')
b.set_group(2, 'on', False)
lightson=False
print ('Lights are off')
time.sleep(0.1)
else: #When output from motion sensor is HIGH
print ('Movement detected - Turning lights on')
command = {"on" : True, "bri" : 255, "sat" : 0, "hue" : 0}
b.set_group(2, command)
lightson=True
print ('Lights are on.')
time.sleep(5)
# added delay to prevent program using 100% cpu time.
time.sleep(0.5)

You can add a time check using datetime module at the start of each iteration to conditionally set your command dictionary and run your PIR code if between certain hours. The button logic code should be run outside of the if blocks to make sure it always works
from datetime import datetime
while True:
now = datetime.now()
# Check to see if it is 5am or later
if now.hour >= 5:
# PIR sensor code here
print("PIR sensor should work now")
# Check to see if between 8pm and 11pm
if now.hour >= 20 and now.hour <= 23:
# Configure command dictionary for specific hours
command = {"on": True,"bri": 255,"sat": 80,"hue": 357}
else:
# Configure command dictionary for regular hours
command = {"on": False}
# Rest of your code including button logic