General
Data bits	5, 6, 7, 8
Stop bits	1, 1.5, 2
MTBF	536.288 Stunden (Telcordia SR-332)

The CA-132I-T from Moxa is an industrial-grade interface card with two RS-422/485 ports, specifically designed for use in embedded systems and harsh industrial environments. The module is based on the PC/104 bus standard and enables serial communication with optical isolation of 2 kV, compensating for voltage differences and electromagnetic interference. It supports an extended operating temperature range of -40 to 85 °C, making it suitable for applications in extreme environments.

Applications

The module is used in industrial automation systems, controls, and data acquisition systems where reliable serial communication under demanding conditions is required. Typical application scenarios include machine control systems, process monitoring systems, and fieldbus connections in manufacturing, energy supply, or rail transport. The high operating temperature and robust construction also make it suitable for mobile or outdoor-operated systems.

Functions and Features in Detail

The CA-132I-T features two 16C550C-compatible UARTs, each supporting a 64-byte FIFO buffer. This enables efficient data transfer with low CPU load. Configuration is done via DIP switches for I/O address and interrupt vector, ensuring flexible integration into various system platforms. Integrated Tx/Rx LEDs are present at each port, visually indicating data traffic and thus simplifying diagnosis of communication issues.

Technology Explained Simply

The RS-422 and RS-485 interfaces enable serial data transmission over long distances with high noise immunity. The RS-422 interface operates in 4-wire mode (separate transmit and receive lines), while RS-485 can operate in both 4-wire and 2-wire mode (shared line for transmit and receive). The 2 kV optical isolation protects the module and connected system from voltage spikes and potential differences, which may arise from grounding differences or electrical discharges. The baud rate can be set between 50 bps and 921.6 kbps, with configurable data bits (5–8), stop bits (1, 1.5, 2), and parity types (None, Even, Odd, Space, Mark). Flow control is via XON/XOFF or disabled.

Compatibility and Accessories

The module is designed for various operating systems, including Windows (DOS to Windows 10/Server 2019, x86/x64, CE 5.0/6.0, XP Embedded), Linux (Kernel 2.4.x, 2.6.x), and UNIX (FreeBSD 4.x, QNX 4, SCO UNIX, OpenServer). Driver support enables easy integration into existing system environments. IRQs (Interrupt Requests) can be set to channels 3, 4, 5, 6, 7, 9, 10, 11, 12, and 15. The connection type is a 20-pin box header, standard for PC/104 systems.

Mounting and Installation

The module is installed directly into a PC/104 system, with mechanical dimensions of 90 x 96 mm. Power supply is 5 VDC with a current draw of 190 mA. Installation requires no additional components; configuration is done via DIP switches on the module. The integrated LEDs serve as visual indicators for operation and data transmission.

Operational Advantages

The high operating temperature range of -40 to 85 °C, optical isolation, and comprehensive driver support ensure high reliability and flexibility. The integrated diagnostic LEDs reduce troubleshooting time during operation. The MTBF (Mean Time Between Failures) is 536,288 hours according to Telcordia SR-332, indicating a very long service life. The module complies with EMC standards such as EN 55032/24, CISPR 32, FCC Part 15B Class A, as well as EMS tests according to IEC 61000-4-2 to -8 and -14. Additionally, it is environmentally compliant according to RoHS, CRoHS, and WEEE. The warranty period is 5 years.