General
Serial standards	2 x RS-232/422/485, 2 x RS-422/485 -
Data bits	5, 6, 7, 8 -
FIFO buffer	128 Bytes
Maximum number of expansion cards per PC	8 Stück
EMC	EN 55032/35 -
Communication control	MU860 -

The Moxa CP-134U-DB9M is a 4-Port-Universal-PCI card for serial communication in industrial and technical applications. The device offers four serial interfaces, which can be configured as RS-232, RS-422, or RS-485 as required, with two ports supporting full compatibility with all three standards. The card is designed for use in PCs with a 32-bit Universal-PCI bus and enables connection to serial devices such as sensors, controls, measuring instruments, or industrial peripheral units. The electrical isolation of 2 kV protects system components from transient voltage spikes and enables reliable communication in electrically harsh environments. The operating temperature of 0 to 55 °C makes the module suitable for use in indoor environments where ambient temperature remains within these limits.

Applications

The CP-134U-DB9M is suitable for applications in automation technology, process monitoring, machine control, and data transfer between industrial devices and PC systems. The support for multiple serial standards (RS-232/422/485) enables connection to various devices commonly found in existing installations. The 2-kV isolation is particularly important in environments with high electrical interference, such as production halls or when high-voltage equipment is used nearby. The integrated LED indicators for transmit (Tx) and receive (Rx) at each port facilitate diagnosis and troubleshooting during operation.

Functions and Equipment in Detail

The card features a communication controller of type MU860, compatible with the 16C550C. This ensures stable and widely supported operation across various operating systems. The FIFO buffer size is 128 bytes per port, enabling efficient data transfer at higher baud rates. The maximum number of installable cards per PC is eight, supporting scalability for systems with many serial end devices. The baud rate can be set between 50 bps and 921.6 kbps, allowing flexible adaptation to different transmission speeds. Data bits can be set to 5, 6, 7, or 8 bits, stop bits to 1, 1.5, or 2, and parity to None, Even, Odd, Space, or Mark. Flow control is achieved via RTS/CTS or XON/XOFF, preventing data loss during overload.

Technology Explained Simply

The serial interface of the CP-134U-DB9M enables data transmission bit by bit over a cable. RS-422 and RS-485 technologies use differential signals (e.g., Tx+, Tx−) to improve noise immunity and transmission range compared to RS-232. The 2-kV isolation electrically separates the serial signals from the PCI bus to prevent damage from voltage spikes. The DB44 connector on the card allows connection to a DB9 male cable, which is the standard for serial connections in industry. The integrated LEDs indicate active transmission and reception, which is helpful for troubleshooting.

Compatibility and Accessories

The card supports a wide range of operating systems, including Windows (from DOS to Windows 10, x86/x64), Linux (kernels 2.4.x to 5.x), and UNIX systems such as QNX 6, SCO OpenServer, UnixWare 7, Solaris 10, and FreeBSD. Drivers are available for various platforms, facilitating integration into existing system environments. The PCI bus compatibility allows use in standard PCs with the appropriate slot. The card is designed for use in systems with a stable 5 VDC power supply, with a power consumption of 850 mA.

Installation and Mounting

Installation is performed by inserting the card into a free 32-bit Universal-PCI slot of the computer. Connection to external devices is made via the included DB9 male cable, which connects to the DB44 female socket on the card. Configuration is done using the provided drivers and software tools, enabling settings for baud rate, parity, data bits, and flow control. The maximum of eight cards per PC allows for a high number of serial ports in a single system.

Advantages in Operation

The 2-kV isolation increases system reliability and lifespan, especially in environments with electrical interference. Support for multiple serial standards (RS-232/422/485) and flexible configuration of baud rate, data bits, and parity enable broad compatibility with various devices. The integrated LEDs simplify diagnostics, and the high MTBF (480,209 hours according to Telcordia SR332) indicates high operational reliability. The 5-year warranty underscores the product’s quality and durability.

The card is designed for use in industrial environments where stable and reliable serial communication is required. The operating temperature of 0 to 55 °C and storage temperature of −40 to 85 °C allow flexible use under various climatic conditions. The relative humidity of 5 to 95 % (non-condensing) is suitable for use in dry to slightly humid environments. Compliance with standards EN 55032/35, CISPR 32, FCC Part 15B Class B, as well as IEC 61000-4-2 and -4-3, ensures low electromagnetic emissions and high immunity to external interference. Certification according to RoHS, CRoHS, and WEEE demonstrates the product’s environmental compatibility.