M5Stack Limit Switch Unit

The Unit Limit from M5Stack is a limit switch sensor. When the switch bar is pressed, the digital single of the Unit would change from 3.3V to 0V, which may generate a limit signal to MCU or other peripherals.

Applied for multiple mechanical equipment to achieve limit protection.

Features

• Contact limit switch
• Long durability, up to 400K times lifetime
• Multiple installation methods

Package Contents

• 1x Unit limit
• 1x HY2.0 4-pin Cable (20cm)

Specifications

Switch Bar Length	16mm
Mechanical Lifetime	400K Times
Power Supply	DC 5V
Output Logical Signal	DC 3.3V
Standby Current	DC5V@2mA
Operation Current	DC5V@3mA
Net Weight	6.3g
Gross Weight	11.4g
Product Size	37 * 24 * 9.5mm
Package Size	92 * 135mm

Resources

• Product Documentation
• Schematic
• Arduino Example

Pinout

M5CORE - PORT B	G36
UNIT Limit	Input

Arduino Example

#include 

#define KEY_PIN 36 

void setup() {
    M5.begin();  
    M5.Lcd.setTextSize(4);
    M5.Lcd.print(("\n  UNIT-LIMIT\n  Example"));

    pinMode(KEY_PIN, INPUT_PULLUP);
}

void loop() {
    if (!digitalRead(KEY_PIN)) {
        M5.Lcd.setCursor(0, 130);
        M5.Lcd.print(("  Hit limit!"));
    } else {
        M5.Lcd.setCursor(0, 130);
        M5.Lcd.println(("            "));
    }
    delay(100);
}