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, SU2-BALLAD or SU3-ENSEMBLE 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).