CompactPCI® Serial Quad Port Isolated RS-485 Interface • Mezzanine Expansion Module • Rear I/O Transition Module

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 SUB-RIO is basically a rear I/O transition module for CompactPCI® Serial systems. The board is equipped with four isolated rear panel RS-485 ports. High speed RS-485 balanced line transceivers with internal 5kV isolation barrier provide for optimum noise and EMC immunity.

In addition, the SUB-RIO can be configured as a mezzanine expansion module, suitable e.g. for the CompactPCI® Serial cards SU1-TWIST (isolated RS-485), SU2-BALLAD (isolated RS-232), SUA-RIO (isolated RS-232), and the SUB-RIO itself. When used as mezzanine board in addition to a carrier card, the SUB-RIO doubles the number of ports available from four to eight, and allows also mixed configurations RS-232 and RS-485. When used as a rear I/O transition module, the SUB-RIO is equipped with the CompactPCI® Serial backplane connector rJ4, sourced from either the SU1-TWIST or SU2-BALLAD octal UART cards via P4 RIO.
When used as a mezzanine expansion module, the backplane connector rJ4 is not populated. Instead, TTL-level UART ports are passed via on-board stacking connectors M51 to M84, for either top or bottom mount assemblies, with a common 8HP rear (or front) panel.

The isolated RS-485 ports are wired to Micro-D rear (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. As an alternate, the SUB-RIO can be equipped with classic D-SUB 9-pin connectors, attached by means of flat cable assemblies (on-board headers PU5 to PU8).

Downloads & Ressources

Application Note

General Information


Ordering Information

  • RIO Serial Interface OnBoard 4xRS485 isolated via microDSub optional LED Displays


  • PICMG® CompactPCI® Serial standard (CPCI-S.0)
  • Rear I/O transition module
  • CompactPCI® Serial backplane connector rJ4
  • Dimensions 100x80mm2 (3U), 4HP rear panel width
  • Suitable for CompactPCI® Serial octal UART peripheral cards SU1-TWIST and SU2-BALLAD (matching SU1 and SU2 backplane connector P4)
  • Expands front card to 8 ports in total (4 x front panel connectors, 4 x rear panel)
  • Any 4 + 4 port mix of isolated RS-232 and RS-485

Simplified Block Diagram

Contact Us