UNO Q / App Lab: How do I read MCU pin D8 and print in Python console via Bridge?

Official Hardware UNO Family UNO Q
1

Board/Env

  • Board: Arduino UNO Q
  • Environment: Arduino App Lab (Python + MCU sketch in one app)

Goal:

I want the LED to turn on when the switch is pressed and turn off when the switch is released. I also want to read the data from pin D8, where my switch is connected, and send that value to the Linux side using a Bridge function so I can print it in the Python console.

MCU (C++ / sketch.ino)

  • Reads D8 with INPUT_PULLUP
  • Turns the LED ON while the switch is pressed (and OFF when released)
  • Exposes a read_d8() function via the Router Bridge so Python can fetch the value

Python (main.py)

  • Polls read_d8() through the Bridge
  • Prints only on change to keep the console tidy

My code for reference

Sketch.ino
`#include "Arduino_RouterBridge.h"

const uint8_t SWITCH_PIN = 8;

int read_d8();
void set_led_state(bool state);

void setup() {
pinMode(SWITCH_PIN, INPUT_PULLUP);
pinMode(LED_BUILTIN, OUTPUT);
Bridge.begin();
Bridge.provide("read_d8", read_d8);
Bridge.provide("set_led_state", set_led_state);
}

void loop() {
}

int read_d8() {
return digitalRead(SWITCH_PIN);
}

void set_led_state(bool state) {
// LOW state means LED is ON
digitalWrite(LED_BUILTIN, state ? LOW : HIGH);
}`

main.py
`from arduino.app_utils import *
import time import sleep

led_state = False
last = None

def loop():
global last, led_state
v = Bridge.call("read_d8")
if v is not None and v != last:
print("D8 =", v)
last = v
led_state = not led_state
Bridge.call("set_led_state", led_state)
sleep(1)

App.run(user_loop=loop)`

2

Have you tried your app of post #1? Is it working? Is it the LED_BUILTIN are you talikng? And always use code tags <code/> when posting codes:

Sketch.ino

#include "Arduino_RouterBridge.h"

const uint8_t SWITCH_PIN = 8;

int read_d8();
void set_led_state(bool state);

void setup() {
  pinMode(SWITCH_PIN, INPUT_PULLUP);
  pinMode(LED_BUILTIN, OUTPUT);
  Bridge.begin();
  Bridge.provide("read_d8", read_d8);
  Bridge.provide("set_led_state", set_led_state);
}

void loop() {
}

int read_d8() {
  return digitalRead(SWITCH_PIN);
}

void set_led_state(bool state) {
  // LOW state means LED is ON
  digitalWrite(LED_BUILTIN, state ? LOW : HIGH);
}

main.py

from arduino.app_utils import *
import time import sleep

led_state = False
last = None

def loop():
global last, led_state
v = Bridge.call("read_d8")
if v is not None and v != last:
print("D8 =", v)
last = v
led_state = not led_state
Bridge.call("set_led_state", led_state)
sleep(1)

App.run(user_loop=loop)

Notes:
1. In Python, indentation and spacing are part of the language syntax. Please ensure that the above main.py script follows correct indentation and spacing, then re-submit it. Remember that a colon (:) marks the start of a block, and the lines belonging to that block must be indented consistently on the following lines.

2.

From your python script, it appears that --

You press switch at the MCU side
The information is known to MPU via Bridge
MPU sends "turn On" signal to MCU via Bridge

If I am corect, then the above quoted line shoud be modified as:
Turns the LED ON while the switch is pressed (and OFF when released) and let it be known to MPU which sends the "turn On/Off" value to MCU.

3. Add codes with python script so that when MCU driven LED_BUILTIN is On, the MPU driven LED1_R is also On.

image
image1035×582 138 KB

3

Hey there. thank you for helping. it is working now.

4

What have you done to make it working?