Comprehensive Product Summary – Rayon Technology P5914 UPCI 4-Port RS232/RS422/RS485 Selectable 5V PCI Card

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### 1. Product Overview

Product Name: UPCI 4-Port RS232/RS422/RS485 Selectable 5V Only Card
Model Number: P5914
Series: UPCI Intelligent Serial Communication Card Series
Article Number: P5914
Manufacturer: Rayon Technology Co., Ltd.
Manufacturer Address: 2F, No. 177, Chung Shan 2 Rd., Lu Chou City, Taipei Hsien, Taiwan
Contact Information:
- Telephone: +886-2-82858362
- Fax: +886-2-82857065
- Email: rayon@ms1.hinet.net / info@rayontech.com.tw
- Websites: [www.rayontech.com.tw](http://www.rayontech.com.tw), [www.computex.com.tw/rayon](http://www.computex.com.tw/rayon)

Product Type: Intelligent PCI serial communication interface card
Form Factor: Standard PCI expansion card (5V only)
Primary Function: Provides four independent serial communication ports selectable between RS232, RS422, and RS485 modes.
Target Users: Industrial automation, embedded systems, communication servers, and multi-serial port PC applications requiring flexible serial connectivity.

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### 2. Key Features

- Multi-Protocol Serial Support: Each of the four ports can be independently configured as RS232, RS422, or RS485, providing maximum flexibility for mixed communication environments.
- 5V PCI Bus Compatibility: Designed specifically for 5V PCI slots, ensuring stable operation in legacy and industrial PC systems.
- Intelligent Plug & Play Architecture: Fully PCI Plug & Play compliant, with automatic I/O address and IRQ assignment handled by the PCI BIOS.
- High Compatibility: Supports a wide range of operating systems including DOS, Windows 95/98/Me, Windows NT, Windows 2000/XP, Windows 7/8/10, Linux, and SCO OpenServer.
- Auto Data Direction Control (RS485): Built-in automatic data direction control for RS485 communication eliminates the need for manual RTS signal handling, simplifying half-duplex communication.
- 16550A UART Compatibility: Each port uses a 16550A-compatible UART with 16-byte FIFO buffers, ensuring reliable high-speed data transmission and reduced CPU overhead.
- Flexible Connector Options: Ships with a DB37 female to 4×DB9 male breakout cable (DB25 male version available upon request).
- Compact Design: Small form factor (120 mm × 100 mm) suitable for standard desktop or industrial PC enclosures.
- Industrial-Grade Reliability: Operates in wide environmental conditions (0°C–55°C, 10–95% RH) suitable for industrial and laboratory use.
- Shared IRQ Mapping: Efficient resource utilization through a single shared IRQ for all four ports, minimizing system conflicts.
- Selectable Baud Rate: Each port supports baud rates from 50 to 115,200 bps, covering most serial communication requirements.
- Extended Product Line: Part of Rayon’s 5V-only PCI serial card family, offering 4-port and 8-port variants for different application scales.

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### 3. Technical Specifications

Physical Characteristics:
- Dimensions: 120 mm (L) × 100 mm (W)
- Weight: Approximately 100–150 g (typical for PCI card of this size)
- Form Factor: Standard PCI card (33 MHz, 5V signaling)
- Material: Multi-layer PCB with gold-plated PCI edge connector and high-quality electronic components
- Color: Standard green PCB

Electrical Characteristics:
- Bus Interface: PCI 2.1 compliant, 33 MHz, 5V signaling
- Power Requirement: 5V DC only (drawn from PCI slot)
- Voltage Tolerance: 5V ±5%

Serial Communication Controller:
- Type: 16550A-compatible UART
- Clock Frequency: 1.8432 MHz
- FIFO Buffer: 16-byte transmit and receive buffers per port
- Interrupts: Single shared IRQ assigned by PCI BIOS
- I/O Mapping: Six 8-byte I/O address blocks assigned automatically by PCI BIOS

Port Configuration:
- Number of Ports: 4 independent serial ports
- Interface Standards: RS232, RS422, RS485 (individually selectable per port)
- Baud Rate Range: 50 bps to 115,200 bps
- Connector Type:
- DB37 female on card (via breakout cable)
- DB9 male connectors (standard cable)
- DB25 male connectors (optional cable)
- Signal Support:
- RS232: TXD, RXD, RTS, CTS, DTR, DSR, DCD, GND
- RS422: Differential TX/RX pairs
- RS485: Differential data pair with auto-direction control

Environmental Conditions:
- Operating Temperature: 0°C to 55°C
- Storage Temperature: 0°C to 65°C
- Operating Humidity: 10% to 95% RH (non-condensing)
- Storage Humidity: 5% to 95% RH (non-condensing)

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### 4. Functionality

The P5914 UPCI 4-Port Serial Card functions as a multi-interface communication adapter that allows a host PC to connect to multiple serial devices simultaneously. Each of the four ports can be configured independently to operate in RS232, RS422, or RS485 mode, enabling mixed-protocol environments within a single system.

Operational Principle:
- The card interfaces with the host system via the PCI bus, using 5V signaling.
- Upon installation, the PCI BIOS automatically assigns I/O addresses and IRQ resources, ensuring conflict-free operation.
- Each port’s communication mode (RS232/RS422/RS485) is selectable through onboard configuration or software settings.
- The integrated 16550A UART provides buffered data transmission, reducing CPU load and improving throughput.
- In RS485 mode, the Auto Data Direction Control feature automatically manages the transmit/receive switching, simplifying half-duplex communication.

Typical Use Cases:
- Industrial automation systems requiring multiple serial device connections (PLCs, sensors, controllers).
- Communication servers and data acquisition systems.
- Laboratory instrumentation and test equipment interfaces.
- Point-of-sale (POS) systems and kiosks.
- Legacy equipment integration in modern PCs.
- Multi-protocol serial communication environments.

Compatibility:
- Fully compatible with standard PCI 5V slots (not suitable for 3.3V-only PCI or PCIe slots).
- Supported operating systems include:
- DOS
- Windows 95/98/Me
- Windows NT
- Windows 2000/XP
- Windows 7/8/10
- Linux
- SCO OpenServer
- UNIX-based systems

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### 5. Components & Accessories

Included Components:
- P5914 PCI Card: Main 4-port intelligent serial interface card.
- DB37F to 4×DB9M Cable (P485 Cable): Breakout cable providing four DB9 male connectors for external serial devices.
- Documentation: User manual and installation guide (digital or printed).

Optional Accessories:
- DB37F to 4×DB25M Cable (A400 Cable): Alternative breakout cable for DB25 connectivity.
- TB485 Kit: DB9 female to RS485 terminal block adapter for direct wiring of RS485 networks.
- Additional Cables: Custom-length or shielded cables available upon request.

Connector Details:
- On-Card Connector: DB37 female
- External Connectors: Four DB9 male or DB25 male (depending on cable type)
- Signal Pinouts: Standard RS232/RS422/RS485 pin assignments per EIA/TIA specifications.

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### 6. Installation & Setup

System Requirements:
- Available 5V PCI slot (33 MHz)
- Compatible operating system (DOS, Windows, Linux, or UNIX)
- Administrative privileges for driver installation

Installation Steps:
1. Power off the host PC and disconnect from power.
2. Insert the P5914 card into an available 5V PCI slot, ensuring firm seating.
3. Secure the card bracket to the chassis.
4. Connect the provided DB37-to-DB9/DB25 breakout cable.
5. Power on the system; the PCI BIOS will automatically detect and assign resources.
6. Install the appropriate driver or configure the serial ports using the operating system’s device manager.
7. Configure each port’s communication mode (RS232/RS422/RS485) as required.
8. Connect external serial devices and verify communication using terminal software or diagnostic tools.

Configuration Options:
- Port mode selection (RS232/RS422/RS485) via jumper or software utility (depending on revision).
- Baud rate, parity, data bits, and stop bits configurable through software.
- IRQ and I/O addresses automatically managed by PCI BIOS (no manual configuration required).

Mounting Options:
- Standard PCI bracket for desktop or industrial PC chassis.
- Optional low-profile bracket available for compact systems (on request).

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### 7. Performance & Capabilities

Data Transmission:
- Supports full-duplex communication in RS232 and RS422 modes.
- Supports half-duplex communication in RS485 mode with automatic direction control.
- Reliable operation up to 115,200 bps per port.

Efficiency:
- 16550A UART with FIFO buffering minimizes CPU load during high-speed data transfer.
- Shared IRQ design optimizes system resource usage.
- PCI Plug & Play ensures seamless integration without manual configuration.

Capacity:
- Four independent serial channels per card.
- Multiple cards can be installed in a single system for expanded port capacity (subject to available PCI slots and IRQ resources).

Limitations:
- Designed for 5V PCI slots only (not compatible with 3.3V or PCI Express).
- Maximum baud rate limited to 115,200 bps (standard UART limitation).
- Environmental operation limited to 0–55°C (not suitable for extreme industrial environments without additional cooling).

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### 8. Standards & Compliance

Interface Standards:
- RS232 (EIA/TIA-232)
- RS422 (EIA/TIA-422)
- RS485 (EIA/TIA-485)
- PCI Local Bus Specification Revision 2.1

Electrical & Safety Compliance:
- Designed to meet CE and FCC Class B requirements (typical for PCI interface cards).
- RoHS-compliant manufacturing process (lead-free soldering and materials).

Software & Driver Compliance:
- Compatible with standard serial communication APIs and driver models across supported operating systems.
- Supports standard COM port emulation for legacy software compatibility.

Industry Standards:
- UART 16550A compatibility ensures interoperability with standard serial communication software and hardware.
- Conforms to industrial communication standards for RS422/RS485 differential signaling.

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### 9. Additional Information

Warranty:
- Standard manufacturer’s warranty (typically 1 year) covering defects in materials and workmanship.
- Extended warranty options available through authorized distributors.

Technical Support:
- Email and phone support provided by Rayon Technology.
- Driver downloads, manuals, and FAQs available on the official website.
- Firmware and driver updates periodically released for new OS compatibility.

Maintenance:
- No routine maintenance required.
- Periodic inspection recommended to ensure secure cable connections and dust-free PCI contacts.
- Avoid exposure to excessive humidity or temperature beyond specified limits.

Product Line Relationship:
The P5914 belongs to Rayon’s family of 5V-only PCI serial communication cards, offering various port configurations:

| Model | RS232 Ports | RS422 Ports | RS485 Ports |
|--------|--------------|--------------|--------------|
| P5984 | 4 | 0 | 0 |
| P5984P | 4 | 0 | 0 |
| P5985 | 0 | 4 | 4 |
| P5914 | 4 | 4 | 4 |

This makes the P5914 the most versatile model, supporting all three serial standards on each port.

Applications Summary:
- Industrial control and automation
- Data acquisition and monitoring
- Communication gateways and protocol converters
- Laboratory instrumentation
- POS and retail systems
- Embedded computing and legacy system integration

Product Longevity:
- Designed for long-term availability and support in industrial and embedded markets.
- Backward-compatible with older PCI-based systems, ensuring extended lifecycle usability.

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### Summary

The Rayon Technology P5914 UPCI 4-Port RS232/RS422/RS485 Selectable 5V PCI Card is a robust, flexible, and intelligent serial communication solution designed for industrial and professional applications requiring multiple serial interfaces within a single PCI expansion card. With independent port configuration, broad OS compatibility, and reliable 16550A UART performance, it provides a cost-effective and efficient means to expand serial connectivity in both legacy and modern PC systems. Its 5V-only design ensures compatibility with traditional PCI architectures, while its auto-configuration and auto-direction control features simplify installation and operation. The P5914 stands out as a versatile, high-quality communication interface card suitable for a wide range of serial communication tasks across industrial, commercial, and technical environments.