> ## Documentation Index
> Fetch the complete documentation index at: https://docs.pads4.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Communication port settings

These properties define the **RS-232 communication port settings**, ensuring successful data transmission between your **presentation system** and an **external device**.

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## **Communication Port Settings**

### **Communication Port**

* Select the **COM (serial)** or **LPT (parallel)** port used for **RS-232 communication**.

### **Baud Rate**

* Defines the **transmission speed** in **symbols per second (bps)**.
* Common values: **1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200**.
* Must match the **external device settings**.

### **Parity**

Determines how **parity checking** is applied for **error detection**.

| **Option** | **Description**                                     |
| ---------- | --------------------------------------------------- |
| **None**   | No parity check (default).                          |
| **Even**   | Ensures an even number of **1s** in the data frame. |
| **Odd**    | Ensures an odd number of **1s** in the data frame.  |
| **Mark**   | Always sets the parity bit to **1**.                |
| **Space**  | Always sets the parity bit to **0**.                |

### **Data Bits**

* Defines the number of **data bits per frame**.
* Standard values: **5, 6, 7, or 8 bits** (default: **8**).
* Must match the **external device settings**.

### **Start Bits**

* Specifies the **leading bits** before actual data transmission.
* Standard value: **1 bit**.

### **Stop Bits**

* Specifies the **end of transmission bits**.
* Standard values: **1, 1.5, or 2 bits** (default: **1**).
* Used to **separate data packets**.

### **Handshake**

Defines **flow control** between sender and receiver to prevent **data loss**.

| **Option**   | **Description**                                                                            |
| ------------ | ------------------------------------------------------------------------------------------ |
| **None**     | No handshake (default).                                                                    |
| **XOn/XOff** | Software-based handshake. Uses special characters to control data flow.                    |
| **RTS/CTS**  | Hardware-based handshake using Ready-to-Send (RTS) and Clear-to-Send (CTS) signals.        |
| **DTR/DSR**  | Hardware-based handshake using Data Terminal Ready (DTR) and Data Set Ready (DSR) signals. |

### **Read Timeout**

* **Time limit (in milliseconds)** for receiving a **response from the external device**.
* If no response is received within this time, a **timeout error occurs**.

### **Write Timeout**

* **Time limit (in milliseconds)** for successfully **sending a command**.
* If data cannot be transmitted within this time, a **timeout error occurs**.

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## **Remarks**

* The **correct RS-232 settings** for communication with your **external device** can be found in its **user manual**.
* **Incorrect port settings** may result in **failed communication** or **unexpected device behavior**.

### **Important**

* The communication port settings **must match** those of the **external device**.
* These settings apply **only during playback**, so **RS-232 commands will only be sent if the specified port is available on the playback PC**.