The **FCR-16E-R** is an electronic component primarily classified as a **Rotary Coded Switch** (often used for hex or decimal encoding). These parts are commonly manufactured by companies like **Nidec Copal Electronics** or **Fujisoku**. Below is a detailed breakdown of its electronic specifications and characteristics. --- ### 1. General Specifications The FCR series represents a compact, surface-mount or through-hole rotary switch designed to provide binary-coded outputs to a microcontroller or logic circuit. | Parameter | Specification (Typical) | | :--- | :--- | | **Part Series** | FCR-16 (16 positions) | | **Suffix "E"** | Often denotes packaging or specific terminal style (e.g., Lead-free/RoHS) | | **Suffix "R"** | Typically indicates "Real Code" output (Standard Binary) | | **Number of Positions** | 16 (Hexadecimal: 0-9, A-F) | | **Terminal Pitch** | Standard 2.54mm (0.1") | | **Switching Rating** | 5V DC, 100mA (Logic Level) | --- ### 2. Internal Electronic Functionality The switch acts as a manual interface that converts a physical rotation into a 4-bit digital signal. * **Binary Coded Hexadecimal (BCH):** As the dial is turned, it opens or closes four internal tracks connected to pins. * **Common Terminal:** There is a "Common" (C) pin. Depending on the dial position, the Common pin is shorted to pins 1, 2, 4, and 8 in various combinations. * **Logic Example:** * Position **0**: All switches open (Binary 0000). * Position **7**: Pins 1, 2, and 4 are shorted to Common (Binary 0111). * Position **F (15)**: All pins (1, 2, 4, 8) are shorted to Common (Binary 1111). --- ### 3. Pin Configuration The "16E-R" model usually features a 3-3 or 2-3 pin layout depending on the mounting style. | Pin Number | Function | Description | | :--- | :--- | :--- | | **C** | Common | The input voltage (usually GND or VCC) | | **1** | Bit 0 ($2^0$) | Least Significant Bit (LSB) | | **2** | Bit 1 ($2^1$) | Second Bit | | **4** | Bit 2 ($2^2$) | Third Bit | | **8** | Bit 3 ($2^3$) | Most Significant Bit (MSB) | --- ### 4. Typical Applications These parts are used in "Set and Forget" scenarios where a hardware address or mode must be defined without a digital UI: * **Address Setting:** Setting the ID for a device on a RS-485 or CAN bus. * **Mode Selection:** Choosing between 16 different firmware operating modes. * **Configuration:** Adjusting hardware parameters on a PCB (Industrial automation). --- ### 5. Circuit Implementation When integrating the FCR-16E-R, it is standard practice to use **Pull-up Resistors** if the Common pin is tied to Ground. ```c // Pseudo-code for reading the FCR-16E-R int readSwitch() { int b0 = digitalRead(PIN_1); int b1 = digitalRead(PIN_2); int b2 = digitalRead(PIN_4); int b3 = digitalRead(PIN_8); // Combine bits into a single integer (0-15) return (b3 << 3) | (b2 << 2) | (b1 << 1) | b0; } ``` ---