How to Send Commands to an Arduino from a Python Script

These tutorials assume some basic understanding of Python syntax.

[hansyboi]

I've looked at dozens of arduino Python tutorials and none of them have worked so it was such a relief to see mine working after I followed yours. Thank you so much!

[steelcock]

import serial.tools.list_ports

ports =
serial_inst = serial.Serial()

ports_list = []

for port in ports:
ports_list.append(str(port))
print(str(port))

val: str = input('Select Port: COM')

for i in range(len(ports_list)):
if
port_var = f'COM{val}'
print(port_var)

serial_inst.baudrate = 9600
serial_inst.port = port_var
serial_inst.open()

while True:
command: str = input('Arduino Command: (ON/OFF): ').upper()
print(command)


if command == 'EXIT':
exit(0)




#define LED_pin 9
#define LED_error_pin 8

void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
pinMode(LED_pin, OUTPUT);
pinMode(LED_error_pin, OUTPUT);
}

void loop() {
// put your main code here, to run repeatedly:
//String msg = "STATIC";
if (Serial.available() > 0) {
String msg = Serial.readString();
if (msg == "ON") {
digitalWrite(LED_pin, HIGH);
}
else if (msg == "OFF") {
digitalWrite(LED_pin, LOW);
}

else {
digitalWrite(LED_error_pin, HIGH);
delay(100);
digitalWrite(LED_error_pin, LOW);
}
}
}

[hieule-chyb]

why i can't connect between python and arduino in same com port?

[vishal.s]

please let know if it posssible to use this in esp32 cam module also

[superpayaseria]

So I'm trying to write 1, 000's of commands for a humanoid robot project. I started coding in python. But as far as I can tell with the last few lessons Arduino ide only allows like a few commands at a time. So is it possible to write super complex code in python and use an arduino for the main processing unit for the entire robot??? Or will the arduino ide not handle it?

[benbenameur]

Hello
I am looking for the equivalent of : in matlab .

[anmaleno]

how can we remove the delay between sending the message and lighting the LED? THANKS

[neknek]

hello, i tried to practice your code, but it seems I have lacking on my side,
it shows some comments regarding error at line#15. what does this mean?


if + str(val)):

AttributeError: 'str' object has no attribute 'startswitch'. Did you mean: 'startswith'?

[elyakimlev]

Cool. I was wondering how I could combine computer vision with an Arduino controlled robotic arm. I thought I'd have to use Raspberry Pi, which isn't capable enough for real-time computer vision. Now I'm thinking of using this method to do the resource intensive action of computer vision on my PC and then just send the coordinates of the detected objects to the Arduino for it to decide how to move the robotic arm.

[nanakoii]

How to fix this issue?? I'm using windows and I was run the file as administrator and still not work

Traceback (most recent call last):
File "D:\MIDI\test.py", line 21, in <module>
serialInst.open()
File "C:\Users\NHQEN\AppData\Local\Programs\Python\Python311\Lib\site-packages\serial\serialwin32.py", line 64, in open
raise SerialException("could not open port {!r}: {!r}".format(self.portstr, ctypes.WinError()))
could not open port 'COM7': PermissionError(13, 'Access is denied.', None, 5)

[linyih]

there seems to be lagging when input command from pc till the LED is on, is there a way to improve it?

[nityanandadas]

Nice video.
I am automating a power supply by Python with SCPI Commands.
At the same time I need to use Arduino to switch on and off control by Python.
Can I synchronise the two devices - the power supply and the Arduino or, they are automatically synchronised with the PC time?
Regards

[francescocassini]

Your code is fantastic, but if I have to send a NUMBER (also as string) to control a servo motor, how can I change the .ino files to get a string ("0" or"180") and convert to an INT in .ino files? I have seen other videos that use FIRMATA, but the servo has always a bad beahaviour and many delays to reach the position. So I believe that it's better realize a system as yours. Thanks in advance if you can help me