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pcl-844 image
8-port Intelligent RS-232 Card

Ordering Information


Introduction Return to top of page

The PCL-844 Intelligent 8-port RS-232 Card is designed for lab and industrial applications where a PC needs to communicate with many serial devices such as terminals, modems and other instruments. If you need RS-422 interfaces for longer distance, connect the PCL-844 to a PCL-8442 to get 8 isolated RS-422 ports. You can install up to four PCL-844 cards for a total of 32 ports in any ISA bus based 286/386/486/Pentium PC.

The PCL-844's on-board 12 MHz 80286 processor takes over the communication load from the host PC. When you process large amounts of data from/to multiple serial ports, servicing the interrupts alone consumes a big percentage of your PC's CPU time. The PCL-844 serves as a high speed dedicated interrupt processor. Its CPU directly controls the board's CD180 RISC-based UART, guaranteeing 38,400 bps performance over eight high speed data ports.

The PCL-844 is virtually a self contained computer in its own right. It contains 512 KB of dual-port RAM which you can use to store and run programs. The dual-port RAM maps into the host system's address space to give you the fastest possible data transfer between the PCL-844 and the PC memory.

When the PCL-844 initializes, it downloads the driver software (which functions like a PC's BIOS) into on-board SRAM. This improves performance and makes version upgrading easy without hardware redundancy.

Each PCL-844 comes with software drivers, PC-ComLIB, for DOS and Windows. These drivers support most common languages, including C, Pascal, Visual Basic, Quick Basic, assembly and Clipper. The PC-ComLIB package also includes the DataScope data viewer, terminal emulator and serf-diagnostic utilities for easy troubleshooting and debugging.

Applications Return to top of page

  • Data acquisition and control with RS-232/RS-422 based devices
  • PLC monitoring and control
  • Instrument controller, distributed control system
  • Modem server, database server, POS controller
  • Multi-user system

Features Return to top of page

  • 12 MHz 80286 processor, CD180 RISC-Based UART, 512 KB dual port RAM.
  • Baud rate up to 38,400 bps with eight ports on line
  • Complete RS-232 modem control signals
  • Maps to just 16 KB of system memory Choose one of six addresses from C8000 to DC000
  • Many IRQ options: 2, 3, 4, 5, 7, 10, 11, 12 or 15
  • Easy-to-use menu driven installation program
  • LEDs on connection box let you monitor the TxD/RxD status of every port
  • Links to peripherals up to 4,000 feet from controller (RS-422) with PCL-8442

Specifications Return to top of page


  • Number of ports: 8
  • Processor: 12 MHz 80286
  • Dual-port RAM: 512 KB
  • SRAM: 16 KB
  • UART: RISC-based CD180
  • Total ports in one system: 32
  • Operating temperature: 32 to 122 degF (0 to 50 degC)
  • Power consumption: 5V@1.5A, 12V@120 mA, -12V@180 mA
  • Dimensions: 13.3" x 4.7" (338mm x 120mm)
  • Weight: 1.5 lb. (0.67 Kg)

RS-232 Interface

  • Signals: TxD, RxD, RTS, CTS, DTR, DSR, DCD and GND
  • Mode: asynchronous full duplex
  • Communication rate: 50 to 38,400 bps
  • Stop bits: 1 or 2
  • Parity: even, odd or none
  • Data bits: 7 or 8

DOS Driver

  • Optimized, small-size resident (TSR) interrupt driver
  • Supports standard DOS COM: ports
  • Supports C, BASIC, Pascal, Clipper and assembly
  • Includes DataScope data viewer, terminal emulator and self diagnostic utilities for easy troubleshooting and debugging

Windows Driver

  • DLL driver for Windows 3.0/3.1
  • Supports Visual Basic, Microsoft C , Borland C and Turbo Pascal

Ordering Information Return to top of page

8-port Intelligent RS-232 Card
Isolated 8-port RS-232/422 Converter (110 V)
Isolated 8-port RS-232/422 Converter (220 V)
8-port RS-232 connection box
1-to-8 RS-232 cable
USA Office

Address: 1480 Gulf Road, Suite 837,
PO Box 1280
Point Roberts, WA 98281

Western Canada - Vancouver BC

Tel:1.800.663.6001 or 1.604.925.6150
Address: 2454 Haywood Ave
West Vancouver, BC V7V 1Y1

Eastern Canada - Markham, Ontario

Tel:1.800.465.0164 or 1.905.513.7027