Black Box IC107A-R2 RS-232 to RS-422/485 Interface Converter (Data Only)

Black Box IC107A-R2 RS-232↔RS-422/485 Data-Only Serial Interface Conversion for 4-Wire Full-Duplex Communication

The Black Box IC107A-R2 is a serial interface converter designed to provide electrical signal conversion between asynchronous RS-232 and RS-422/485 communication standards. The unit performs physical-layer conversion only and is intended for use in systems where compatibility between differing serial interfaces is required without alteration to data format, protocol structure, or timing behavior.

The converter supports 4-wire, full-duplex operation and is suitable for both point-to-point and multipoint serial communication configurations. It is designed to interconnect legacy RS-232 equipment with RS-422 or RS-485-based systems while maintaining transparent data transmission characteristics.

Interface conversion and signaling characteristics

• Bidirectional conversion between asynchronous RS-232 and RS-422/485 electrical signaling standards
• Support for 4-wire, full-duplex communication with separate transmit and receive signal paths
• Compatibility with point-to-point and multipoint serial wiring topologies
• User-configurable RS-232 port operation for DTE or DCE roles
• User-selectable RS-422/485 line termination to support terminated or unterminated installations

Architecture and operational scope

The IC107A-R2 provides independent differential transmit and receive pairs on the RS-422/485 interface, identified as TXA/TXB and RXA/RXB, enabling simultaneous bidirectional data transfer. On the RS-232 side, the converter uses a DB25 female connector and supports the data and control leads commonly required for asynchronous serial communication.

Control signals on the RS-232 interface are used solely to manage electrical driver enable behavior on the RS-422/485 side, depending on internal configuration. The converter may be configured for continuous driver enable or for control via selected RS-232 handshake lines. These control functions are electrical in nature and do not imply interpretation of protocol state or communication intent.

The “Data Only” designation indicates that the IC107A-R2 performs no modem functions, protocol interpretation, synchronous clocking, or data processing. The unit does not generate, recover, or manage timing signals beyond those inherent to asynchronous serial transmission, and it does not modify or analyze the content of transmitted data.

Integration and typical usage context

The IC107A-R2 is housed in a standalone enclosure and includes a DB25 female connector for RS-232 connections and a four-pin terminal block for RS-422/485 wiring. Front-panel indicators provide visual status of transmit activity, receive activity, and power state, supporting basic operational verification during installation and use.

This converter is used in environments where RS-232-based equipment must communicate reliably with RS-422 or RS-485 systems, particularly in installations that benefit from the longer cable distances and noise immunity associated with differential signaling. Its defined scope and lack of higher-layer functionality make it suitable for integration into systems where serial communication behavior is managed entirely by the connected equipment.

Applications

• Connecting RS-232 host equipment to RS-422/485-connected industrial devices
• Extending asynchronous serial communication over long copper cable runs
• Implementing point-to-point or multipoint 4-wire full-duplex serial links