3540 - 4 Port RS-232/422/485 PC/104 Serial Card (C4.104-ULTRA)
CE is a mandatory standard for products on the market in the European Economic Area. By CE marking a product, the manufacturer ensures that the item meets the essential safety requirements set out in the applicable CE directive.
This product fully adheres to the Restriction of Hazardous Substances Directive 2002/95/EC, RoHS for short.  The directive covers the restriction of use of certain hazardous substances in electrical and electronic equipment and was adopted in February 2003 by the European Union.
This product has a lifetime warranty against product failure (excludes user or enviromental damage).
This product either conforms to a PC/104 form factor or supports PC/104 expansion. PC/104 (or PC104) is an embedded computer standard controlled by the PC/104 Consortium which defines both a form factor and computer bus.
The Federal Communications Commission (FCC) is an independent agency of the United States government that sets standards and governs the testing of conducted and radiated emissions such as EMI.
3540 PC 104 Serial Card

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Version information
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4 Port RS-232/422/485 PC/104 Serial Card (MOQ 25 pieces)
Peripheral information
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40-Pin IDC Ribbon Cable to (4) DB9 Male Connectors, 14" in Length
40-Pin IDC Ribbon Cable to DB37 Male, 6" in Length
DB37 Female to (4) DB9 Male, 36" in Length - for 7402, 7404, 7904, 3440, etc.
DB9 Female to DB9 Female, 72" in Length - RS-422 207M SMPTE Cable
40-Pin IDC to 40-Pin IDC Ribbon Cable, 18" in Length - Standard IDE Cable
DB9 Female (RS-422) to DB9 Female (Opto 22 Optomux) Converter
Terminal Block - IDC40 to (4) DB9 Male Connectors - for 354x Multi-Port Interface Adapters
Terminal Block Kit - DB37 Male and DB37 Female to 37 Screw Terminals
* Lead time is indicative and is subject to change at time of ordering. Next business day delivery on in-stock products only (when ordered before 3pm).
** Contact us for quantity or project pricing.
† Additional delivery charge may be incurred for certain postcodes (calculated at checkout)

3540 overview

  • Asynchronous Communication
  • RS-232/422/485 Software Selectable Interface
  • Ports: 4
  • UART: 16C854
  • Max. data rate: 921.6Kbps
  • Max data distance: up to 4000ft
  • Termination, pull-ups, and pull-down resistors for each port are software selectable
  • Automatic RS-485 enable and disable
  • Connector: 40way IDC
  • Operating temperature : 0 to +70C
  • SeaCOM software drivers included
  • (MOQ 25 pieces)
The 3540 is the first PC/104 serial interface module to provide four software-selectable RS-232, RS-422, or RS-485 ports. RS-232, RS-422, or RS-485 mode may be selected independently via software command for each of the four ports, eliminating the need for setting jumpers or DIP switches.

The board is designed using the XR16C864 UART, which provides a 128-byte FIFO, 8 times larger than boards designed with 16C550 compatible parts.

The larger buffers allow error free operation even in high-speed applications. In RS-485 mode the C4-104.ULTRA offers automatic control of the RS-485 driver enable for trouble free network master arbitration.

Additionally, the C4-104.ULTRA allows RS-485 network termination, critical to robust multi-drop communication, to be selectively added to the circuit via a simple software command.

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