EKF - Short Profile
EKF - Short Profile


CompactPCI® Serial • Quad Port Isolated RS-485 Interface

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Ordered List
Product Information
Block Diagram, Configuration

Block Diagram

RS-485 Transceiver


Application Note

General Information
Concise Guide

Smart Solution


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CompactPCI® Serial • Quad Port Isolated RS-485 Interface

Proven and reliable, RS-485 (EIA/TIA-485) stays a popular fieldbus communication interface, due to simple installation via low cost twisted pair copper cables, up to 1200m length.

The SU1-TWIST is a peripheral slot card for CompactPCI® Serial systems, based on PCI Express®. The board is equipped with four isolated front panel RS-485 ports. High speed RS-485 balanced line transceivers with internal 5kV isolation barrier provide for optimum noise and EMC immunity.

The SU1-TWIST is equipped with an octal PCI Express® to UART bridge. The 950-style UARTs are compatible with many asynchronous serial applications and protocols. Four isolated EIA/TIA-485 transceivers are wired to Micro-D front panel connectors, individually configurable for full-duplex operation (4+1 wire cable) or half-duplex (2+1 wire cable), either point-to-point or multipoint applications. Another four UART channels are available via the CompactPCI® Serial backplane connector P4 for versatile rear I/O usage.



SU1-TWIST Simplified Block Diagram

Block Diagram
Summary of Features

CompactPCI® Serial
  • PICMG® CompactPCI® Serial standard (CPCI-S.0)
  • Single size Eurocard 3U 4HP 100x160mm2
  • Suitable for CompactPCI® Serial peripheral slot (PCI Express® enabled)
  • CompactPCI® Serial backplane connector P1 for PCI Express®, single lane link
  • Option CompactPCI® Serial backplane connector P4 for rear I/O

  • Pericom® PCI Express® Octal UART PI7C9X7958
  • Eight high performance 950-class UARTs
  • 16C550 software compatible
  • 128-Byte FIFO for each transmitter/receiver
  • Baud rate up to 15Mbps
  • XON/XOFF in-band flow control
  • CTS/RTS or DSR/DTR out-of-band control
  • Data frame 5, 6, 7, 8 and 9 bits
  • Clock prescaling 4 to 46
  • Windows® WHQL device driver support

RS-485 Transceivers
  • 5kV rms isolation barrier RS-485/RS-422 transceivers (Analog Devices ADM2682)
  • Configurable as half- or full-duplex
  • ±15 kV ESD protection on RS-485 input/output pins
  • Transceiver data rate 16Mbps max.
  • Connect up to 256 nodes on one PartyLine bus (driver enable control via dedicated UART mode select outputs)
  • Open- and short-circuit, fail-safe receiver inputs
  • High common-mode transient immunity >25 kV/µs
  • Thermal shutdown protection

Front Panel I/O
  • 4 x Front panel Micro-D 9-pin high density male connectors
  • RS-485 front ports isolated against each other and board circuitry
  • On-board DIP-switches for full/half-duplex setting, and line termination on/off
  • Micro-D cable assemblies available, e.g. Micro-D to classic style D-Sub male or female
  • Ordering option D-Sub 9-pin front panel connectors (4 ports require 8HP F/P)
  • Option 2 x D-SUB9 front panel connectors on request (4HP, 2 x micro ribbon flat cable assembly)
  • Option 3 x D-SUB9 front panel connectors on request (4HP, front handle replaced by screw lock)
  • Option 4 x D-SUB9 front panel connectors on request (8HP, 4 x micro ribbon flat cable assembly)

Option Rear I/O
  • Ordering Option CompactPCI® Serial backplane connector P4 for rear I/O
  • 4 x Rear I/O UART ports (TTL Level), wired to P4 for optional usage with RIO module
  • Each rear I/O UART port suitable for versatile use with an appropriate transceiver on a RIO module, e.g. RS-232 or RS-485, isolated or non-isolated
  • Standard rear I/O modules available (SUA-RIO for 4 x RS-232 isolated, SUB-RIO for 4 x RS-485 isolated)
  • Option all 8 ports available for rear I/O (SUC-RIO)
  • EKF offers custom specific rear I/O module design

Environment, Regulatory
  • Designed & manufactured in Germany
  • Certified quality management according to ISO 9001
  • Long term availability
  • Rugged solution (coating, sealing, underfilling on request)
  • RoHS compliant
  • Operation temperature -40°C to +85°C (industrial temperature range)
  • Storage temperature -40°C to +85°C, max. gradient 5°C/min
  • Humidity 5% ... 95% RH non condensing
  • Altitude -300m ... +3000m
  • Shock 15g 0.33ms, 6g 6ms
  • Vibration 1g 5-2000Hz
  • MTBF 43.5 years
  • EC Regulations EN55022, EN55035, EN60950-1 (UL60950-1/IEC60950-1)

SU1-TWIST Transceiver Schematics - FDX/HDX

Simplified Transceiver Schematics - Full Duplex

SU1-TWIST Transceiver Schematics - FDX/HDX

Simplified Transceiver Schematics - Half Duplex

SU1-TWIST Micro-D Connector Pin Assignment

Micro-D Connector Pin Assignment

SU1-TWIST w. SUB-RIO Assembly

SU1-TWIST w. SUB-RIO Eight Port 4HP Assembly
Ordering Information
Please refer to List 21 for popular SKU
EKF is an ISO-9001 certified company
EKF Elektronik GmbH • Philipp-Reis-Str. 4 • 59065 Hamm • Germany
Phone +49 (0)2381/6890-0 • Fax +49 (0)2381/6890-90 • E-Mail