The Sealevel Systems COMM+4.PCI is a 4-port serial interface card for PCI bus systems, supporting RS-232, RS-422, and RS-485 electrical standards. It enables integration with diverse serial devices in industrial automation, data acquisition, and control applications. The card employs a 16C864 UART with 128-byte transmit and receive FIFOs, delivering sustained performance across programmable baud rates up to 460.8K bps. RS-422 and RS-485 interfaces extend communication distances to 4000 ft, while RS-485 multi-drop capability supports up to 31 devices on a single bus. The card occupies a standard-profile PCI slot and includes a 36-inch cable with four DB9 male connectors.
Technical Specifications
• Host Interface: PCI (3.3V and 5V compatible)
• Ports: 4
• Electrical Standards: RS-232, RS-422, RS-485
• Communications Chip: 16C864 UART
• FIFO Buffers: 128-byte transmit and receive
• Maximum Data Rate: 460.8K bps
• Transmission Distance: Up to 4000 ft (RS-422/485)
• Operating Temperature Range: 0°C to 70°C
• Connector Type: DB9 male
• Cable Length: 36 inches (included)
• Form Factor: Standard profile
– Key Features
• Dual differential signaling on RS-422 delivers high noise immunity for long-distance links
• RS-485 multi-drop architecture addresses up to 31 devices per bus
• Configurable two-wire or four-wire RS-485 modes with DIP switch selectable termination, pull-up, and pull-down resistors
• Auto-enable functionality presents ports as standard COM ports to the operating system
• 128-byte FIFOs reduce software interrupt overhead and improve throughput
– Typical Applications
• Industrial control and automation systems
• Multi-device sensor and instrument networks
• Long-distance serial data acquisition
• Legacy system integration requiring mixed RS-232/422/485 support
– Compatibility & Integration
Supported by Sealevel SeaCOM software drivers for Microsoft Windows and Linux environments. Compatible with universal PCI buses rated 3.3V or 5V. Card is classified as legacy with limited availability.
