《NI官方labview培训教材Lesson 9-11 [ppt]》.ppt

LV Basics I Lesson 9Data Acquisition and Waveforms TOPICS Plug-in DAQ devices Data Acquisition in LabVIEW Analog Input Data Logging Analog Output Counters Digital I/O Measurement Software Framework Channels and Tasks The DAQ Signal Accessory NI-DAQmx versus Traditional NI-DAQ NI-DAQmx Data Acquisition NI-DAQmx Data Acquisition Task Types Analog Input Analog Input Task Timing and Triggering Data Logging It is often necessary to permanently store data that is acquired from the DAQ device LabVIEW includes the ability to read and write a LabVIEW Measurement File LabVIEW Measurement File is an ASCII text file Analog Output Analog Output Task Timing and Triggering Counters Digital Input and Output Digital I/O can read from or write to a line or an entire digital port A digital port is a collection of digital lines Lesson 10Instrument Control TOPICS Instrument Control Overview GPIB Communication and Configuration Instrument I/O Assistant Virtual Instrument Software Architecture (VISA) Instrument Drivers Serial Port Communication Waveform Transfers GPIB Communication Standards Introduction GPIB Hardware Specifications Max cable length between devices = 4 m (2 m average) Max cable length = 20 m Max number of devices = 15 (2/3 powered on) GPIB Software Architecture — Windows Configuring GPIB Board and Instruments Measurement Automation Explorer (MAX) What is the Instrument I/O Assistant? Accessed through a LabVIEW Express VI Sets up device communication and data parsing step by step through a configuration interface Communicating with an Instrument Virtual Instrument Software Architecture Platform independent VISA is the backbone of the IVI and Plug Play Instrument Drivers VISA Terminology Resource—Instrument, Serial Port, or Parallel Port Session—Connection to a Resource Instrument Descriptor—Resource location Format: Interface Type::Address::INSTR Examples: Instrument Descriptor Syntax VISA Resource Name Exact name and location of the instrument Use the VISA Res