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104-COM-8SM Family

PC/104 Eight-, Four-, and -Two Port Serial Communication Boards

Features

  • 8, 4, or 2 independent asynchronous serial COM ports
  • Field selectable RS-232, RS-422 and RS-485, independent for each port
  • Auto-RTS feature makes half-duplex RS-485 communications effortless
  • Speeds up to 921.6K with 64-byte FIFO (RS-232 is 230K max)
  • Fixed bias and jumper selectable termination provided on each transmit and receive channel simplifies cabling
  • Programmable individual non-volatile base addresses and IRQs simplifies installation
  • Low power required: +5VDC at 80 mA typical
  • Operates as a standard COM port in all operating systems
  • RoHS Available. Please contact us for ordering information
  • Designed, made, supported, and manufactured in the USA

Factory Options: (call for pricing and availability)

  • 0 to 70 C and -40 to +85 C versions available
  • 4 port version available
  • RoHS Available. Please contact us for ordering information
This is an eight-, four-, or two-port, asynchronous, serial communication board designed for use on the PC/104 bus. It supports RS-232, RS-422 or RS-485 communications. The board may be installed in any standard PC/104 stack. Connections are made via two 40 pin IDC type right angle connectors. Common applications include POS, gaming systems, machine monitoring, military and high-density networking.

Type 16780 UARTS are used as the asynchronous communication elements. These include 64-byte transmit/receive FIFO buffers to protect against lost data in multitasking systems while maintaining 100% compatibility with the original IBM serial port (software compatible with Windows COM port drivers).

A crystal oscillator located on the board permits precise baud rate capability up to 115,200. Higher speeds, up to 921.6K, are achieved by installing a jumper on the board.

The addresses of the individual channels and IRQ are stored in non volatile memory on the board and loaded into programmed logic when the board is initially powered.

AUTO TRANSCEIVER CONTROL

In RS-485 multidrop communications individual drivers must be enabled when needed and then disabled after use to permit all ports on the network to share a two-wire or four-wire cable. The 104-COM-8SM and 104-COM4SM use an automatic (AUTO) control software selectable channel by channel. The driver is enabled (and the receiver disabled) when data is ready to be transmitted. When transmission is complete, the driver remains enabled for the transmission time of one additional character and then is disabled. This is ideal for use in Windows based applications as the standard Windows COM port driver is used to ensure compatibiliy.

UTILITY SOFTWARE

Tools provided include samples to demonstrate COM port initialization in multiple languages. Driver software is provided by Windows and all other major operating systems, including Linux (16550 compatible.) A graphical Setup program is provided to assist with jumper selections for protocol and address configuration.


Available Reference Manuals

Available Software Downloads

Available Datasheets

Drivers and Downloads

Full list of available Downloads: Software Packages, Drivers, Manuals, and other documents


Custom Software

ACCES also offers Custom Software Services for our products. Our prices are unbelievably low, often as inexpensive as free! If you need something tweaked to support your needs, or an entire enterprise application developed from scratch, it is definitely worth your time to inquire with us, first.

Further information about available ACCES Software:

Redistributing Windows Drivers
A list of ACCES drivers and the files that compose them under different versions of Windows, so you can easily redistribute ACCES cards and drivers.

Specifications


Communications Interface

  • I/O Connections: Via two 40 pin IDC type right angle connectors. There are eight pins per port plus common grounds.
  • Character Length: 5,6,7, or 8 bits
  • Parity: Even, odd, or none
  • Stop Interval: 1, 1.5, or 2 bits
  • Serial Data Rates: Up to 115.2K baud, asynchronous. A faster range of rates, up to 921.6K, is achieved by jumper selection (RS-232 is 230K max).
  • Multidrop: Compatible with RS-485 specifications. Up to 32 drivers and receivers allowed on line. Driver/Receivers used are type 75ALS180. Compatible with RS-422 specifications. Up to ten receivers allowed on line.
  • Address: ISA BUS address is set by jumpers on the board. A "Default" jumper determines whether the channel addresses are sequential or loaded from non-volatile memory on the board.
  • Interrupts: Individual IRQs for each channel are stored onboard in non-volatile memory.
  • Receiver Input Sensitivity: ±200 mV differential input
  • Common Mode Voltage Range: +12V to -7V
  • Transmitter Output Drive Capability: 60 mA with thermal shutdown. Jumper selectable terminations for input and output, by channel, are provided. Bias is also provided.

Environmental

  • Operating Temperature Range: 0 to +70°C, (-40 to +85°C Optional)
  • Storage Temperature Range: -50 to +120°C
  • Humidity: 5% to 95% RH, non-condensing
  • Power Required: +5 VDC at 80 mA typical, all outputs open

CE testing & approval must be done at the system level, in the designed enclosure, and is not done on individual boards.


 
ModelPrice (USD)
104-COM-8SM249.00
104-COM-4SM199.00
104-COM-2SM169.00

Acquisition, Control, Communication: Engineering and Systems