National Instruments NI 6115, NI 6120 Timing and Digital I/O

Appendix B Common Questions

© National Instruments Corporation B-5 NI 6115/6120 User Manual

Timing and Digital I/O

What types of triggering can be hardware-implemented on the

NI6115/6120?

Hardware digital and analog triggering are both supported on the

NI6115/6120.

If I’m using one of the general-purpose counter/timers on the

NI6115/6120, but I do not see the counter/timer output on the I/O

connector, what am I doing wrong?

If you are using NI-DAQ or LabWindows/CVI, youmust configure the

output line to output the signal to the I/O connector. Use the

Select_Signal call in NI-DAQ to configure the output line. Bydefault,

all timing I/O lines except EXTSTROBE* are high-impedance.

What are the PFIs and how do I configure these lines?

PFIs are Programmable Function Inputs. These lines serve as connections

to virtually all internal timing signals.

If you are using NI-DAQ or LabWindows/CVI, use the Select_Signal

function to route internal signals to the I/O connector, route external signals

to internal timing sources, or tie internal timing signals together.

If you are using NI-DAQ with LabVIEW and you want to connect external

signal sources to the PFI lines, you can use AI Clock Config, AI Trigger

Config, AO Clock Config, AO Trigger and Gate Config, and Counter Set

Attribute advanced-level VIs to indicate which function the connected

signal serves. Use the Route Signal VI to enable the PFI lines to output

internal signals.

Table B-1. Signal Name Equivalencies

Hardware

Signal Name

LabVIEW

Route Signal NI-DAQ Select_Signal

TRIG1 AI Start Trigger ND_IN_START_TRIGGER

TRIG2 AI Stop Trigger ND_IN_STOP_TRIGGER

STARTSCAN AI Scan Start ND_IN_SCAN_START

SISOURCE —ND_IN_SCAN_CLOCK_TIMEBASE

CONVERT* AI Convert ND_IN_CONVERT

Contents

Main Page Important Information Warranty Copyright Trademarks Patents Compliance FCC/Canada Radio Frequency Interference Compliance Determining FCC Class FCC/DOC Warnings Class A Compliance to EU Directives Contents Chapter 4 Connecting Signals Page About This Manual Conventions National Instruments Documentation Related Documentation Introduction About the NI 6115/6120 Using PXI with CompactPCI What You Need to Get Started Software Programming Choices NI-DAQ National Instruments ADE Software Optional Equipment Custom Cabling Unpacking Safety Information Page Page Installing and Configuring the NI 6115/6120 Installing the Software Installing the Hardware Page Configuring the Device National Instruments Corporation 3-1 NI 6115/6120 User Manual Hardware Overview DAQ - STC RTSI Bus Figure 3-1. NI 6115 Block Diagram Analog Input The following sections describe in detail each AI category. Input Mode Note The inputs are differential only in the sense that the ground loops are broken. I/O Connector Input Polarity and Input Range Considerations for Selecting Input Ranges Input Coupling Analog Output Analog Trigger Figure 3-3. Analog Trigger Block Diagram for the NI 6115/6120 Figure 3-4. Below-Low-Level Analog Triggering Mode Page Antialiasing Filters Phase-Locked Loop Circuit Correlated Digital I/O Timing Signal Routing Page Programmable Function Inputs Device and RTSI Clocks RTSI Triggers Page Figure 3-13. PXI RTSI Bus Signal Connections Connecting Signals I/O Connector Figure 4-1. I/O Connector Pin Assignment for the NI 6115/6120 I/O Connector Signal Descriptions Table 4-2. Signal Descriptions for I/O Connector Pins Table 4-2. Signal Descriptions for I/O Connector Pins (Continued) Table 4-3. Analog I/O Signal Summary for the NI 6115 Table 4-2. Signal Descriptions for I/O Connector Pins (Continued) Table 4-4. Analog I/O Summary for the NI 6120 Table 4-5. Digital I/O Signal Summary Types of Signal Sources Floating Signal Sources Table 4-5. Digital I/O Signal Summary (Continued) Ground-Referenced Signal Sources Connecting Analog Input Signals Connections for Ground-Referenced Signal Sources * Figure 4-2. Pseudodifferential Input Connections on the NI 6115 forGro und-Referenced Signals Figure 4-3. Pseudodifferential Input Connections on the NI 6120 forGro und-Referenced Signals Connections for Nonreferenced or Floating Signal Sources * Figure 4-4. Differential Input Connections on the NI 6115 for Nonreferenced Signals Common-Mode Signal Rejection Considerations Working Voltage Range Connecting Analog Output Signals Connecting Digital I/O Signals Correlating DIO Signal Connections Page Power Connections Connecting Timing Signals Page Programmable Function Input Connections DAQ Timing Connections TRIG1 Signal TRIG2 Signal Page STARTSCAN Signal Page CONVERT* Signal AIGATE Signal SISOURCE Signal SCANCLK Signal EXTSTROBE* Signal Waveform Generation Timing Connections WFTRIG Signal UPDATE* Signal UISOURCE Signal General-Purpose Timing Signal Connections GPCTR0_SOURCE Signal GPCTR0_GATE Signal GPCTR0_OUT Signal GPCTR0_UP_DOWN Signal GPCTR1_SOURCE Signal GPCTR1_GATE Signal GPCTR1_OUT Signal Figure4-34 shows the timing requirements for GPCTR1_OUT. Figure 4-35. GPCTR1_OUT Signal Timing Figure 4-36. GPCTR Timing Summary GPCTR1_UP_DOWN Signal FREQ_OUT Signal Field Wiring Considerations Calibration Loading Stored Calibration Constants Self-Calibration External Calibration Page A Specifications Analog Input Input Characteristics DC Transfer Characteristics Table A-1. NI 6115 Analog Input DC Accuracy Information Table A-2. NI 6120 Analog Input DC Accuracy Information Dynamic Characteristics Table A-4. NI6120 Analog Input Dynamic Charac teristics Figure A-1. NI 6115 Total Harmonic Distortion Plus Noise (THD+N) Figure A-2. NI 6120 Total Harmonic Distortion Plus Noise (THD+N) Figure A-3. NI6115 High-Voltage THD + N Figure A-4. NI 6120 High-Voltage THD+ N Figure A-5. NI 6115 THD + N with Filters Stability Analog Output Output Characteristics DC Transfer Characteristics Voltage Output Dynamic Characteristics Stability Digital I/O Timing I/O Triggers Analog Trigger Page Safety Maximum Working Voltage Electromagnetic Compatibility B Common Questions General Information Installing and Configuring the Device Analog Input and Output Page Timing and Digital I/O Page C Technical Support and Professional Services Glossary Numbers/Symbols A B C D E F G H I K L M N O P R S T U V W Index Numerics A B C D E F G H I K L M N O P Q R S Page T U V W