Abaco Systems / Ramix PMC422FP Eight Port Serial Controller

The Abaco Systems PMC422FP is an eight-port serial controller on a PCI Mezzanine Card (PMC) that extends embedded systems with multiple serial communication channels. Designed for VMEbus, CompactPCI, and single-board computer platforms, it consolidates RS-232, RS-422, and RS-485 serial I/O into a single module with flexible signaling options configured via on-board DIP switches.

Technical Specifications

• Form Factor: Standard PMC module


• Serial Channels: 8 ports


• UART Architecture: Octal UART with 16C550-compatible register set


• Receive/Transmit Buffer: 64 bytes per channel (RX and TX)


• PCI Interface: PCI 2.2 compliant, 32-bit data transfers, 33 MHz clock


• Data Transfer Modes: Read/write burst operation; byte, word, and double-word transfers


• Baud Rate Range: 100 bits/sec to 921.6 kbits/sec (up to 6.2 Mb/s with alternative crystal)


• Supported Protocols: RS-232, RS-422, RS-485 (full duplex and half duplex with selectable termination)


• General Purpose I/O: 8-bit switch input; 16-bit timer/counter with 8 general inputs

Key Features

• Multi-protocol support with DIP switch configuration eliminates firmware complexity


• Front panel connectivity options: four ports via RJ-45 connectors or all eight ports via 68-pin SCSI cable


• Rear panel access available with optional PIM422 I/O module on J4


• 64-byte FIFO per channel reduces CPU interrupt overhead


• Full-duplex and half-duplex RS-485 with termination control

Typical Applications

• Industrial embedded systems requiring multiple serial instruments


• Rugged field deployment in VMEbus or CompactPCI chassis


• Legacy device integration in modernized SBC architectures


• Real-time monitoring and telemetry collection

Compatibility & Integration Works with any host processor featuring a PMC slot. Direct compatibility with VMEbus and CompactPCI backplanes. PCI 2.2 compliant for standard 32-bit, 33 MHz operation.