VXI Technology, Inc.

Starting the Device

The device resets upon application of power. The Optical Attenuators park at the minimum-loss position.

Control Modes

The Optical Attenuators can be operated in two modes: uncalibrated and calibrated. The uncalibrated mode is called Move-To-Absolute-Step mode. In this mode, the user sends movement requests to the internal stepping motor through the Move-To-Absolute-Step interface. The internal stepping motor responds by moving one step up, or one step down as requested. In this mode, there is no conversion of step number to absolute attenuation.

Move-To-Absolute-Step is the simplest mode of operation. This method of operation is typically used when devices are used in a feedback loop to maintain a particular attenuation regardless of absolute position.

The calibrated, absolute conversion mode of operation sends absolute attenuation requests to the Optical Attenuator. The circuitry then translates the commanded absolute request into a motor- step position and rotates the motor accordingly. This method of operation is typically used when the devices are used to calibrate other devices, or to set absolute references within a system.

Both modes of operation are described in detail in the following sections.

Uncalibrated Operation - Move-To-Absolute-Step

The motorized Optical Attenuators are all based on stepping motor technology. The easiest method of using these devices is to simply command the motor to step in one direction, or the other. For our purposes, stepping will increase attenuation, while stepping down will decrease attenuation.

To utilize this mode of operation, simply command the Optical Attenuator to Move-To-Absolute- Step. See the Attenuator Command Set in the Programming section.

Calibrated Operation

The Optical Attenuators are all based on stepping motor technology. Operating in the calibrated mode requires use of the I2C interface on the optical modules.

The I2C interface is a linearized controller, allowing users to select for the attenuator, he absolute attenuation in dB.

It is also possible to command uncalibrated step movements while operating in calibrated mode. Note that following an uncalibrated step, a Query Attenuation command will return invalid data. A subsequent calibrated movement will restore query command validity.

SM8000 Series Operation

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VXI SM8000 Starting the Device, Control Modes, Uncalibrated Operation Move-To-Absolute-Step, Calibrated Operation
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SM8000 specifications

The VXI SM8000 is a versatile and robust modular instrumentation platform that is designed for various testing applications in industries such as aerospace, telecommunications, and military. This advanced test equipment is part of the VXI (Versatile Instrumentation System) standards, which allow for high-speed data acquisition, processing, and analysis.

One of the main features of the VXI SM8000 is its modular architecture, which enables users to configure the system according to their specific testing needs. This flexibility means that users can integrate various modules, including signal generators, oscilloscopes, and digital multimeters, making the system adaptable to a wide range of applications. The modular design also ensures scalability, allowing for easy expansion as test requirements grow.

The VXI SM8000 supports high-speed communication via its advanced backplane design. This design features multiple data buses that facilitate fast communication between modules, ensuring minimal latency and enhanced performance during testing. Moreover, the system is built to accommodate high-density modules, maximizing the amount of test parameters that can be handled simultaneously.

The SM8000 boasts enhanced signal processing capabilities thanks to its digital signal processing (DSP) technology. This feature enables real-time analysis and processing of signals, which is crucial for applications that require rapid feedback and adjustments. Additionally, the system is equipped with high-resolution analog-to-digital converters, ensuring precise measurement and analysis.

One of the key characteristics of the VXI SM8000 is its reliability. Built with robust materials and advanced engineering, the system is designed to endure rigorous testing environments and extreme operating conditions. This durability ensures consistent performance over time, making it a reliable choice for critical applications.

Furthermore, the VXI SM8000 is compatible with various software platforms, enabling seamless integration into existing testing environments. It supports programming languages like LabVIEW and MATLAB, allowing engineers to develop customized test scripts and configurations easily.

In summary, the VXI SM8000 is a powerful and flexible test system that combines modularity, high-speed communication, advanced signal processing, and compatibility with industry-standard software. Its reliability and scalability make it an ideal choice for professionals seeking a comprehensive testing solution across various sectors.
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