The **M2RT-56-R2** is a specific type of **Rotary DIP Switch** manufactured by Nidec Components (formerly Copal Electronics). It is designed to act as a binary or hexadecimal selector for circuits, often used to set device addresses or configurations on a PCB. --- ### 1. Key Technical Specifications | Parameter | Specification | | :--- | :--- | | **Switch Type** | Rotary DIP | | **Number of Positions** | 10 (Decimal / BCD) | | **Output Code** | Real Code (Binary Coded Decimal) | | **Actuator Style** | Flush / Flat (Screwdriver slot) | | **Mounting Type** | Through-hole (THT) | | **Terminal Pitch** | 2.54 mm (Standard) | | **Contact Rating** | 100mA @ 5V DC (Switching) / 100mA @ 50V DC (Non-switching) | --- ### 2. Physical Design and Construction * **Actuator (R2):** The "R2" suffix typically denotes the interface style. In this series, it refers to a **flush-type actuator** that requires a flat-head screwdriver to turn. This prevents accidental changes to the settings. * **Sealing:** These components are usually **washable**. They feature an O-ring or a sealed construction that allows the PCB to be cleaned with solvents after soldering without damaging the internal contacts. * **Compact Footprint:** It follows a 10mm square standard, making it easy to fit into dense electronic layouts. --- ### 3. Electronic Functionality: BCD Output The M2RT-56-R2 uses **Binary Coded Decimal (BCD)** logic. Depending on the position of the dial (0-9), specific output pins are connected to the "Common" pin. **Truth Table (Logic 1 = Connected):** | Position | Pin 1 (2^0) | Pin 2 (2^1) | Pin 4 (2^2) | Pin 8 (2^3) | | :---: | :---: | :---: | :---: | :---: | | 0 | 0 | 0 | 0 | 0 | | 1 | **1** | 0 | 0 | 0 | | 3 | **1** | **1** | 0 | 0 | | 5 | **1** | 0 | **1** | 0 | | 9 | **1** | 0 | 0 | **1** | --- ### 4. Common Applications * **Address Setting:** Used in industrial automation (RS-485 or CAN bus nodes) to give each device a unique ID. * **Mode Selection:** Configuring hardware parameters like baud rate or operation modes without needing a software interface. * **Server/Networking:** Setting identification numbers for rack-mounted hardware. ---