PXI Kits

The PXI serial hardware gives you a variety of solutions for serial communication. The RS-232 boards (PXI-8430, PXI-8432, PXI-8420, and PXI-8422) work with the RS-232 protocol. The RS-485 boards (PXI-8431, PXI-8433, PXI-8421, and PXI-8423) work with the RS-422 and RS-485 protocols. You can use the RS-232 ports for serial communication up to distances of 50 ft. You can connect the RS-485 ports to up to 31 devices using serial cable lengths up to 4,000 ft.

Additionally, the PXI serial boards are available in two-port, four-port, eight-port, and 16-port versions. The two-port versions use DB-9 connectors. The four-port versions use 10-position modular jacks to provide all four connections on a single front panel. Optional cable accessories convert the 10-position modular jacks to either DB-9 or DB-25 connectors with standard pinouts. The eight-port versions use adapter cables to convert the 68-pin connector on the board to eight DB-9 connectors. The PXI-8430/16 uses two adapter cables to convert the two 68-pin connectors on the board to 16 DB-9 connectors. The PXI-8420/16 uses a breakout box to convert the 100-pin connector on the board to 16 DB-9 connectors. Throughout this help file, PXI serial boards refers to all versions of the PXI serial boards.

The isolated PXI boards are designed for applications in harsh environments. Isolated ports provide reliable communication in situations involving ground loops from different ground levels or high common mode voltage induced on the lines in noisy environments. Nonisolated ports may not provide reliable communication in those situations. The isolation between each communication port and the host PC ensures the safe operation of the PC and the devices connected to other ports on the same board, in case of accidental high voltages or line surges on communication lines.

The RS-232 ports are DTE. In the RS-232 specification, Data Terminal Equipment (DTE) and Data Communications Equipment (DCE) refer to the types of equipment on either end of a serial connection. In general, DTE and DCE refer to computer equipment and modems, respectively. For more information about cabling a RS-232 port to other devices, refer to RS-232 DTE vs. DCE.

The RS-485 ports support four hardware transceiver control modes for reliable communication with two and four-wire devices. For more information about transceiver control modes, refer to RS-485 Transceiver Control.

All PXI serial hardware uses standard 16550-compatible UARTs (Universal Asynchronous Receiver/Transmitters) for complete compatibility with standard PC COM ports. The serial hardware contains FIFO (First-In-First-Out) buffers to reduce susceptibility to interrupt latency for faster transmission rates. Full Plug and Play compatibility allows switchless configuration and installation. For more information about the serial hardware specifications and operating conditions, refer to the NI Serial Hardware Guide.

The following table lists the PXI serial board numbers and corresponding board descriptions.

PXI Board Names and Descriptions