Serial communication Python to Arduino

Projects Programming
1

Hello, I would like to know how to send a variable valor from python to arduino,

my program on python looks like this

import serial
ser = serial.Serial(
port='COM3',
baudrate=9600,

)
ser.write(1)

my program on arduino looks like this

#include <LiquidCrystal.h>
LiquidCrystal lcd(8, 9, 4, 5, 6, 7);

int val = 0;

void setup() {
Serial.begin(9600);

}

void loop() {

val = Serial.read();
Serial.print(val);

lcd.begin(16, 2);
if (val == 1){
lcd.print("Ok");}
else if (val > 1){
lcd.print("positive");}
else if (val == -1){
lcd.print("negative");
}
lcd.setCursor(0, 1);

}

despite I put a big valor in the ser.write, the "val" valor in python is the same : -1

do someone have the solution of my problem ?
sorry for my english i'm french :sweat_smile:

2

This Simple Python - Arduino demo should help get you started.

...R