Product Introduction

The NI PXIe-7961R is a 3U single-slot PXIe FlexRIO reconfigurable I/O module, equipped with Xilinx Virtex-5 SX50T field-programmable gate array. It expands signal interfaces through external adapters and does not integrate onboard large-capacity memory. This module focuses on user-defined FPGA hardware logic, high-speed parallel I/O, and low-latency point-to-point data transmission. It can perform hardware-level real-time signal processing, custom protocol parsing, and timing control, and is widely used in various test measurement and prototype development scenarios that require hardware acceleration and high-speed data flow interaction.

Model Interpretation

PXIe represents that the device uses the PXI Express bus and follows the 3U single-slot mechanical standard, compatible with standard PXIe chassis slots. 7961 is the product number of NI FlexRIO programmable FPGA series, corresponding to the basic FPGA master module equipped with Virtex-5 SX50T chip and without onboard independent memory. The suffix R indicates Reconfigurable I/O, which means that users can independently write and burn FPGA logic, flexibly define hardware functions and interface modes. Technical Specifications

FPGA core resources

The module is equipped with Xilinx Virtex-5 SX50T programmable logic chip, featuring 51,200 logic units, 288 digital signal processing slices, and 3,456,000 bit block memory. It supports the development of user logic through graphical or code methods, enabling algorithm hardwareization, custom timing, and dedicated communication protocols.

Bus and transmission performance

It adopts PXIe Gen1 x4 bus, with a bidirectional peak bandwidth of up to 1400 megabytes per second, and a single-directional transmission bandwidth exceeding 700 megabytes per second. It natively supports point-to-point transmission between modules, eliminating the need for data transfer to pass through the host computer, effectively reducing transmission delay.

General I/O electrical parameters

The module is equipped with 132 digital channels, which can be flexibly set to single-ended, differential, or mixed working modes. The maximum transmission rate of single-ended signals is 400 megabits per second, and the maximum LVDS differential signal is 1 gigabit per second. It supports multiple logic levels such as 1.2V, 1.5V, 1.8V, 2.5V, and 3.3V, and is compatible with LVDS and LVTTL standards. It can be connected to the PXI backplane clock, star trigger, and D-Star LVDS trigger signals to meet the requirements of multi-module synchronization.

Physical and environmental parameters

The module is overall in a 3U standard size, with a total weight of approximately 213 grams. When paired with an adapter, the overall power consumption corresponds to 3.3V power supply of 3 amps and 12V power supply of 2 amps. The normal operating temperature range of the equipment is from 0 degrees Celsius to 55 degrees Celsius, meeting the requirements for long-term continuous operation in industrial scenarios.

Interface and communication configuration

Host bus interface

The device uses PXIe Gen1 x4 bus, supporting plug-and-play, and can normally call all synchronization resources on the PXI chassis backplane, such as clocks, star triggers, and D-Star high-speed triggers, to achieve alignment of multiple modules' timings and signal routing within the chassis.

Front panel interface

The panel is equipped with high-density edge connectors, serving as an expansion interface for dedicated adapters, used to connect NI series RF, analog, and digital FlexRIO adapter modules, thereby expanding the external signal input and output capabilities of different types. The module itself has no independent external signal ports.

Driver and software communication

The accompanying driver is NI-FlexRIO and NI-DAQmx, conforming to the IVI universal instrument standard. It can be completed through NI-MAX for hardware identification, device self-check, basic parameter configuration, and firmware management. At the development level, it supports mainstream programming environments such as LabVIEW FPGA, C/C++, and Python, providing complete application programming interfaces for FPGA logic development, channel parameter configuration, point-to-point data flow control, and trigger strategy setting.

Core functions

It has complete user-programmable FPGA capabilities, allowing signal processing algorithms such as filtering, fast Fourier transform, modulation, and demodulation to be deployed on the hardware side, achieving hardware acceleration and significantly reducing the computing pressure on the host computer. With 132 configurable digital channels, it is suitable for multi-level, differential high-speed transmission scenarios, meeting parallel testing and high-speed digital interaction requirements. It supports point-to-point transmission between modules, with extremely low data interaction delay, making it suitable for large-scale multi-channel synchronous data flow. Relying on the rich clock and trigger resources of the PXI backplane, it can achieve high-precision timing synchronization of multiple modules and devices. By connecting with adapters of different specifications, it can flexibly expand RF reception and transmission, high-speed analog acquisition, and dedicated digital interface functions, and a single set of hardware can meet various testing requirements. Applicable scenarios

In the fields of radio frequency and wireless communication, it can be applied to the real-time processing of baseband, signal modulation and demodulation, and beamforming in 5G, radar, and multi-antenna array systems. In semiconductor and chip testing, it is used to build a custom high-speed digital test platform to achieve dedicated protocol parsing, parallel chip testing, and timing verification. In the field of high-speed data acquisition, it can perform real-time pre-processing of vibration, acoustic, and image signals at the front end, reducing data bandwidth and lowering transmission delay. In the direction of industrial control, it can implement industrial real-time bus protocols and high-precision motion control logic in hardware, improving the response speed and stability of the control system. It is also applicable to various research projects and algorithm prototype verification, quickly completing the hardware implementation and iterative testing of communication and signal processing solutions.

User and Maintenance Instructions Instruction Manual

When the power is off, insert the module into the corresponding slot of the standard 3U PXIe chassis and tighten the fixing screws. During the operation of the equipment, hot plugging is strictly prohibited. Throughout the operation, take precautions against static electricity. When connecting the adapter, also perform the operation with the power off to ensure that the interface is aligned and locked, and to prevent pin damage. After starting the equipment, complete the hardware identification and basic parameter settings through NI-MAX. According to the requirements, configure the I/O levels, clock sources, and trigger modes. Then, download the compiled FPGA logic program to the chip for running. When building a multi-module synchronous system, unify the reference clock of all devices, configure the point-to-point transmission routes and trigger signals, and complete the synchronization accuracy verification before conducting the test work.

Maintenance Instructions

Regularly use a dry soft cloth to wipe the surface of the module and the connector positions, remove the accumulated dust, keep the interface in good contact, and strictly prohibit contact with the equipment body. Avoid short circuits or corrosion caused by liquid contact. Regularly check and update the drivers and firmware through NI-MAX to ensure the stability of the equipment operation. When the module is idle for a long time, place it in a dry environment with a temperature ranging from minus twenty to sixty degrees Celsius and a relative humidity of less than 60%. Seal it in an anti-static packaging. When the equipment has abnormal operation, first check the power supply, adapter connection, and software configuration; if there are data transmission errors or logical operation abnormalities, sequentially check the FPGA program, channel parameters, and point-to-point routing settings.