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Chapter 5

Counters

Analog Output Series User Manual

5-2

ni.com

Pause Trigger

You can use pause triggers in edge counting and continuous pulse 
generation applications. For edge counting acquisitions, the counter stops 
counting edges while the external trigger signal is low and resumes when 
the signal goes high or vice versa. For continuous pulse generations, the 
counter stops generating pulses while the external trigger signal is low and 
resumes when the signal goes high or vice versa.

Counter Timing Signals

The following sections contain information on counter timing signals.

Counter Timing Summary

Figure 5-2 shows the timing requirements for the gate and source input 
signals and the timing specifications for the output signals on your device.

Figure 5-2.  

Gate and Source Input Timing Requirements

The gate and out signal transitions shown in Figure 5-2 are referenced to 
the rising edge of the source signal. This timing diagram assumes that the 
counters are programmed to count rising edges. The same timing diagram, 

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Summary of Contents for NI 6711

Page 1: ...DAQ Analog Output Series Analog Output Series User Manual NI 6711 6713 DAQCard 6715 NI 6722 6723 and NI 6731 6733 Devices Analog Output Series User Manual June 2007 370735E 01...

Page 2: ...Lebanon 961 0 1 33 28 28 Malaysia 1800 887710 Mexico 01 800 010 0793 Netherlands 31 0 348 433 466 New Zealand 0800 553 322 Norway 47 0 66 90 76 60 Poland 48 22 3390150 Portugal 351 210 311 210 Russia...

Page 3: ...photocopying recording storing in an information retrieval system or translating in whole or in part without the prior written consent of National Instruments Corporation National Instruments respects...

Page 4: ...t of Communications DOC Changes or modifications not expressly approved by NI could void the user s authority to operate the equipment under the FCC Rules Class A Federal Communications Commission Thi...

Page 5: ...6 Field Wiring Considerations 1 6 Programming Devices in Software 1 7 Chapter 2 I O Connector 68 Pin AO I O Connector Pinouts 2 1 68 68 Pin Extended AO I O Connector Pinout 2 5 Terminal Name Equivalen...

Page 6: ...g an Internal Source 3 9 Using an External Source 3 9 Outputting the AO Sample Clock Signal 3 9 Other Timing Requirements 3 10 AO Sample Clock Timebase Signal 3 11 Master Timebase Signal 3 11 Getting...

Page 7: ...6 Counter 1 Source Signal 5 7 Counter 1 Gate Signal 5 7 Counter 1 Internal Output Signal 5 8 Counter 1 Up Down Signal 5 9 Frequency Output Signal 5 9 Master Timebase Signal 5 9 Getting Started with Co...

Page 8: ...er Methods 9 2 Direct Memory Access DMA 9 2 Interrupt Request IRQ 9 2 Programmed I O 9 2 Changing Data Transfer Methods between DMA and IRQ 9 2 Chapter 10 Triggering Triggering with a Digital Source 1...

Page 9: ...s icon denotes a caution which advises you of precautions to take to avoid injury data loss or a system crash When this symbol is marked on a product refer to the Read Me First Safety and Radio Freque...

Page 10: ...AQmx for Windows software how to install your NI DAQmx supported DAQ device and how to confirm that your device is operating properly Select Start All Programs National Instruments NI DAQ DAQ Getting...

Page 11: ...nts NI DAQmx Base Documentation Getting Started Guide Getting Started with NI DAQmx Base for Linux and Mac Users describes how to install your NI DAQmx Base software your NI DAQmx Base supported DAQ d...

Page 12: ...w to take an NI DAQmx measurement in LabVIEW using the DAQ Assistant VI and Function Reference Measurement I O VIs and Functions Describes the LabVIEW NI DAQmx VIs and properties Taking Measurements C...

Page 13: ...ual Studio NET select Measurement Studio Measurement Studio Reference To create an application in Visual C Visual C or Visual Basic NET follow these general steps 1 In Visual Studio NET select File Ne...

Page 14: ...evice Documentation and Specifications The NI 6711 6713 DAQCard 6715 Specifications contains all specifications for the NI 6711 NI 6713 and NI DAQCard 6715 AO Series devices The NI 6722 6723 Specifica...

Page 15: ...e documents at ni com manuals DAQ specifications and some DAQ manuals are available as PDFs You must have Adobe Acrobat Reader with Search and Accessibility 5 0 5 or later installed to view the PDFs R...

Page 16: ...tioning cables that connect the various devices to the accessories the analog output device and the programming software Refer to the Using Accessories with Devices section for a list of devices and t...

Page 17: ...of the following three timing groups AI two 24 bit two 16 bit counters not used on AO Series devices AO three 24 bit one 16 bit counter General purpose counter timer functions two 24 bit counters You...

Page 18: ...re stored in the EEPROM of the device as calibration constants Before performing a measurement these constants are read out of the EEPROM and are used to adjust the calibration hardware on the device...

Page 19: ...nnector blocks with screw terminals I O connector cables RTSI bus cables Low channel count digital signal conditioning modules devices and accessories For more specific information about these product...

Page 20: ...B 68 TB 68 NI 6731 6733 SH68 68 EP BNC 2110 CB 68LP CB 68LPR SCB 68 TB 68 Table 1 2 Overview of DAQ Accessories for Analog Output Devices Accessory Description BNC 2110 BNC connector block for 68 pin...

Page 21: ...r Board Mating Connectors To access this document go to ni com info and enter the info code rdsmbm Field Wiring Considerations The following recommendations apply for all signal connections to the AO...

Page 22: ...lasses attributes and properties for creating applications for your device NI DAQ 7 x includes two NI DAQ drivers Traditional NI DAQ Legacy and NI DAQmx Each driver has its own API hardware configurat...

Page 23: ...Studio directory contains a link to the ActiveX control examples for use with Measurement Studio NI DAQ Examples VBasic directory contains the examples not associated with Measurement Studio NI DAQmx...

Page 24: ...I O connectors Note Some hardware accessories may not yet reflect the NI DAQmx terminal names If you are using an AO Series device in Traditional NI DAQ Legacy refer to Table 2 1 for the Traditional...

Page 25: ...ND AO 3 AO GND AO GND NC AO GND NC AO GND AO GND NC AO GND D GND PFI 8 CTR 0 SOURCE PFI 7 CTR 1 OUT PFI 4 CTR 1 GATE PFI 3 CTR 1 SOURCE PFI 2 D GND D GND D GND EXT STROBE NC P0 3 P0 7 P0 2 D GND P0 5...

Page 26: ...AO 0 AO GND AO GND AO 3 AO GND AO GND AO 5 AO GND AO 6 AO GND AO GND NC AO GND D GND PFI 8 CTR 0 SOURCE PFI 7 CTR 1 OUT PFI 4 CTR 1 GATE PFI 3 CTR 1 SOURCE PFI 2 D GND D GND D GND EXT STROBE NC P0 3...

Page 27: ...D P0 4 CAL AO 1 AO 0 AO GND AO GND AO 3 AO GND AO GND AO 5 AO GND AO 6 AO GND AO GND NC AO GND D GND PFI 8 CTR 0 SOURCE PFI 7 CTR 1 OUT PFI 4 CTR 1 GATE PFI 3 CTR 1 SOURCE PFI 2 D GND D GND D GND EXT...

Page 28: ...ational Instruments Corporation 2 5 Analog Output Series User Manual 68 68 Pin Extended AO I O Connector Pinout The NI 6723 has two 68 pin I O connectors Figure 2 4 shows the pin assignments for both...

Page 29: ...AO GND AO GND AO 7 AO GND AO GND NC 1 35 2 36 3 37 4 38 5 39 6 40 7 41 8 42 9 43 10 44 11 45 12 46 13 47 14 48 15 49 16 50 17 51 18 52 19 53 20 54 21 55 22 56 23 57 24 58 25 59 26 60 27 61 28 62 29 6...

Page 30: ...ware products The revised terminal names used in this document are usually similar to the names they replace Refer to Table 2 1 for a list of Traditional NI DAQ Legacy terminal names and their NI DAQm...

Page 31: ...URCE CTR 1 SOURCE or CTR 1 SRC PA PB PC P0 P1 P2 PFI PFI PFI_ PFI SCANCLK AI HOLD COMP or AI HOLD SISOURCE AI Sample Clock Timebase STARTSCAN AI SAMP CLK or AI SAMP TRIG1 AI START TRIG or AI START TRI...

Page 32: ...0 7 D GND Input or Output Digital I O signals These pins drive and receive digital signals P0 6 and P0 7 can control the up down signal of Counters 0 and 1 respectively 5 V D GND Output 5 VDC source T...

Page 33: ...apter 5 Counters CTR 1 OUT D GND Output Counter 1 Output Signal This pin emits the Ctr1InternalOutput signal For more information refer to Chapter 5 Counters PFI 5 AO SAMP CLK D GND Input PFI 5 As an...

Page 34: ...ult input for the Ctr0Gate signal Output Counter 0 Gate Signal As an output this pin emits the Ctr0Gate signal This signal reflects the actual gate signal connected to Counter 0 For more information r...

Page 35: ...o D GND to power external circuitry A self resetting fuse protects the supply from overcurrent conditions The fuse resets automatically within a few seconds after the overcurrent condition is removed...

Page 36: ...og Output Circuitry DACs Digital to analog converters DACs convert digital codes to analog voltages DAC FIFO The DAC FIFO enables analog output waveform generation It is a first in first out FIFO memo...

Page 37: ...nge on a voltage output on your AO Series device as follows LSB output voltage range 2resolution of your device where the output range is determined by your reference selection Using AO EXT REF you ca...

Page 38: ...ransitions This uniform glitch energy appears as a multiple of the update rate in the frequency spectrum This reglitch circuit does not eliminate the glitches it only makes them more uniform in size B...

Page 39: ...een samples can be deterministic Hardware timed generations can use hardware triggering For more information refer to Chapter 10 Triggering Hardware timed operations can be buffered or non buffered A...

Page 40: ...must fit within the FIFO size The advantage of using FIFO regeneration is that it does not require communication with the main host memory when the operation is started thereby preventing any problem...

Page 41: ...O Sample Clock that causes all AO channels to update simultaneously Figure 3 3 summarizes the timing and routing options provided by the analog output timing engine Figure 3 3 Analog Output Engine Rou...

Page 42: ...signal on your DAQ device Refer to Device Routing in MAX in the NI DAQmx Help or the LabVIEW Help in version 8 0 for more information Figure 3 4 shows the timing requirements of the ao StartTrigger d...

Page 43: ...se ao Pause Trigger specify a source and a polarity The source can be an external signal connected to any PFI or RTSI 0 6 pin The source can also be one of several other internal signals on your DAQ d...

Page 44: ...e NI DAQmx Help or the LabVIEW Help in version 8 0 for more information Using an External Source You can use a signal connected to any PFI or RTSI 0 6 pin as the source of ao SampleClock Figure 3 6 sh...

Page 45: ...The ao StartTrigger signal starts this counter It is stopped automatically by hardware after a finite acquisition completes or manually through software When using an internally generated ao SampleCl...

Page 46: ...l then you should use the ao SampleClock signal rather than the ao SampleClockTimebase If you do not specify an external sample clock timebase NI DAQ uses the Onboard Clock Figure 3 9 shows the timing...

Page 47: ...Integration Bus RTSI for more information on which signals are available through RTSI Figure 3 10 shows the timing requirements for MasterTimebase Figure 3 10 MasterTimebase Timing Requirements Gettin...

Page 48: ...High speed digital waveform acquisition NI 6731 6733 only Figure 4 1 shows the circuitry of one DIO line Figure 4 1 AO Series Digital I O Block Diagram The DIO terminals are named P0 0 7 on the I O c...

Page 49: ...ble sources The DO waveform generation FIFO stores the digital samples The NI 6731 6733 can use DMA transfers to move data from the system memory to the DO waveform generation FIFO The DAQ device move...

Page 50: ...on You must ensure that the time between two active edges of the do SampleClock is not too short If the time is too short the DO waveform generation FIFO is not able to read the next sample fast enoug...

Page 51: ...software Using an Internal Source To use di SampleClock with an internal source specify the signal source and the polarity of the signal The source can be any of the following signals AO Sample Clock...

Page 52: ...I has several signal conditioning solutions for digital applications requiring high current drive If you configure a PFI or DIO line as an input do not drive the line with voltages outside of its norm...

Page 53: ...d sensing external device states such as the state of the switch shown in the figure Digital output applications include sending TTL signals and driving external devices such as the LED shown in the f...

Page 54: ...Digital Output Digital Waveform Generation Digital Waveform Acquisition NI 6731 6733 only For correlated DIO examples in Traditional NI DAQ Legacy refer to the KnowledgeBase document What Devices Othe...

Page 55: ...ng Counters support two different triggering actions start and pause Only digital triggers can initiate these actions For more information on digital triggers refer to the Triggering with a Digital So...

Page 56: ...on counter timing signals Counter Timing Summary Figure 5 2 shows the timing requirements for the gate and source input signals and the timing specifications for the output signals on your device Figu...

Page 57: ...ts in an uncertainty of one source clock period with respect to unsynchronized gating sources The output timing parameters are referenced to the signal at the source input or to one of the internally...

Page 58: ...l Counter 0 Gate Signal You can select any PFI as well as many other internal signals like the Counter 0 Gate Ctr0Gate signal The Ctr0Gate signal is configured in edge detection or level detection mod...

Page 59: ...se on TC and toggle output polarity on TC The output polarity is software selectable for both options Figure 5 5 shows the behavior of the Ctr0InternalOutput signal Figure 5 5 Ctr0InternalOutput Signa...

Page 60: ...R 0 OUT is set to high impedance at startup Figure 5 6 shows the relationship of CTR 0 OUT and Ctr0InternalOutput Figure 5 6 CTR 0 OUT and Ctr0InternalOutput Counter 0 Up Down Signal You can externall...

Page 61: ...ing Requirements The maximum allowed frequency is 20 MHz with a minimum pulse width of 10 ns high or low There is no minimum frequency For most applications unless you select an external source the 20...

Page 62: ...ity is software selectable for both options Figure 5 9 shows the behavior of the Ctr1InternalOutput signal Figure 5 9 Ctr1InternalOutput Behavior You can use Ctr1InternalOutput in the following applic...

Page 63: ...put clock by the numbers one through 16 The input clock of the frequency generator is software selectable from the internal 10 MHz and 100 kHz timebases The output polarity is software selectable This...

Page 64: ...ounting Edges Frequency Measurement Period Measurement Pulse Width Measurement Semi Period Measurement Pulse Generation You can perform these measurements through programmed I O interrupt or DMA data...

Page 65: ...ng When using the PFI pin as an input you can individually configure each PFI for edge or level detection and for polarity selection You can use the polarity selection for any of the timing signals bu...

Page 66: ...ut PFI pins are labeled with the timing signal that can be output on it For example PFI 8 is labeled PFI 8 CTR 0 Source The following timing signals can be output on PFI pins AO Start Trigger Signal A...

Page 67: ...scription of which routes are possible on your device click the Device Routes tab in Measurement Automation Explorer Timing Signal Routing The DAQ STC provides a flexible interface for connecting timi...

Page 68: ...configurable For example the signal routing multiplexer for controlling the ao SampleClock signal is shown in Figure 7 1 Figure 7 1 Signal Routing Multiplexer on Analog Output Devices Figure 7 1 shows...

Page 69: ...our device can damage your device and the computer NI is not liable for any damage resulting from signal connections that exceed the maximum ratings The 10 programmable function interface PFI pins lab...

Page 70: ...r more information about routing signals in software refer to the NI DAQmx Help Table 7 1 Signal Routing in Software Language Program Function LabVIEW NI DAQmx DAQmx Export Signal vi and DAQmx Connect...

Page 71: ...ation To access this document go to ni com info and enter the info code rdrtcp Note The NI DAQCard 6715 does not use the RTSI bus RTSI Triggers The seven RTSI trigger lines on the RTSI bus provide a f...

Page 72: ...PCI RTSI bus signal connection Figure 8 1 PCI RTSI Bus Signal Connection RTSI Bus Connector Switch RTSI Switch RTSI Trigger 7 Trigger 0 6 DAQ STC Ctr0 Source Ctr0Gate Ctr0InternalOutput Ctr0Out Ctr1So...

Page 73: ...mebase to generate the necessary timing signals for controlling DAC updates or general purpose signals at the I O connector This timebase is also called the Master Timebase or Onboard Clock For more i...

Page 74: ...le Devices With the RTSI bus and the routing capabilities of the DAQ STC there are several ways to synchronize multiple devices depending on your application NI recommends that you use a common timeba...

Page 75: ...ndard CompactPCI chassis you cannot use PXI specific functions but you can still use the basic plug in device functions For example the RTSI bus on a PXI AO Series device is available in a PXI chassis...

Page 76: ...ata transfer speed is tightly coupled to the rate at which the CPU can service the interrupt requests If you are using interrupts to acquire data at a rate faster than the rate the CPU can service the...

Page 77: ...ormation refer to the Analog Output Triggering section of Chapter 3 Analog Output and the Counter Triggering section of Chapter 5 Counters Triggering with a Digital Source Your DAQ device can generate...

Page 78: ...DAQ device to perform an action in response to a trigger from a digital source The action can affect analog output generation counter behavior For more information refer to the Analog Output Triggerin...

Page 79: ...analog output AO digital I O DIO and timing I O TIO devices for PCI bus computers The NI 6711 features four AO channels with 12 bit resolution eight lines of TTL compatible DIO two 24 bit counter time...

Page 80: ...onnector and the NI 6713 has eight channels of voltage output at the I O connector The reference for the AO circuitry is software selectable per channel The reference can be either internal or externa...

Page 81: ...put Timing Control Digital I O Trigger Counter Timing I O RTSI Bus Interface DMA IRQ Bus Interface Address Data Address Control EEPROM Control AO Control Calibration Control DMA IRQ Register Decode FP...

Page 82: ...r timers for TIO a 68 pin AO I O connector Because the NI DAQCard 6715 have no DIP switches jumpers or potentiometers they are easily software configured and calibrated For the NI DAQCard 6715 connect...

Page 83: ...12 Bit DAC AO 4 Amp AO 5 12 Bit DAC AO 6 12 Bit DAC AO 7 12 Bit DAC AO 5 Amp AO 6 Amp AO 7 Amp Data AO 0 12 Bit DAC AO 0 Amp AO 1 12 Bit DAC AO 2 12 Bit DAC AO 3 12 Bit DAC AO 1 Amp AO 2 Amp AO 3 Amp...

Page 84: ...ls with 13 bit resolution eight lines of TTL compatible DIO two 24 bit counter timers for TIO a 68 pin extended AO I O connector Because the NI 6722 6723 have no DIP switches jumpers or potentiometers...

Page 85: ...Bus 13 Bit DAC 13 Bit DAC 13 Bit DAC 13 Bit DAC 13 Bit DAC 13 Bit DAC 13 Bit DAC EEPROM PFI Trigger Timing Digital I O 8 16 Bit ADC x4 x4 Load DAC Update Busy Clear DMA IRQ DAQ STC Analog Output Timi...

Page 86: ...f TTL compatible DIO two 24 bit counter timers for TIO a 68 pin AO I O connector Because the NI 6731 6733 have no DIP switches jumpers or potentiometers they are easily software configured and calibra...

Page 87: ...Digital I O Trigger Counter Timing I O RTSI Bus Interface DMA IRQ Bus Interface Address Data Address Control EEPROM Control AO Control Calibration Control DMA IRQ Register Decode FPGA DAQ STC Bus Inte...

Page 88: ...generate is determined by the update clock frequency fu and the number of samples per cycle Sc The onboard 20 MHz clock that generates fu can only be divided by an integer For example suppose you wan...

Page 89: ...for the outputs of the NI 6713 is 0 V with an accuracy of 200 mV When the computer is powered on the output values might go to 100 110 mV which are within the specifications When you run LabVIEW or th...

Page 90: ...l Instruments Application Engineers make sure every question receives an answer For information about other technical support options in your area visit ni com services or contact your local office at...

Page 91: ...ni com calibration If you searched ni com and could not find the answers you need contact your local office or NI corporate headquarters Phone numbers for our worldwide offices are listed at the front...

Page 92: ...of or minus Ohms Percent Plus or minus Positive of or plus A A Amperes the unit of electric current A D Analog to digital AC Alternating current ADC Analog to digital converter an electronic device o...

Page 93: ...ht lines The name used for a counter physical channel is an exception because that physical channel name is not the name of the terminal where the counter measures or generates the digital signal 2 Vi...

Page 94: ...DAQ devices DAQ STC Data acquisition system timing controller an application specific integrated circuit ASIC for the system timing requirements of a general A D and D A system data acquisition DAQ 1...

Page 95: ...mmands the device accepts E EEPROM Electrically erasable programmable read only memory ROM that can be erased with an electrical signal and reprogrammed ESD Electrostatic Discharge a high voltage low...

Page 96: ...ds and so on A module contains everything required to occupy one or more slots in a mainframe SCXI and PXI devices are modules monotonicity A characteristic of a DAC in which the analog output always...

Page 97: ...omputers electrical storms welders radio transmitters and internal sources such as semiconductors resistors and capacitors Noise corrupts signals you are trying to send or receive NRSE Nonreferenced s...

Page 98: ...to express the rate at which a digitizer or D A converter or DAQ device samples an analog signal scan interval Controls how often a scan is initialized is regulated by the AI SAMP signal scan rate Re...

Page 99: ...y An upgrade to the earlier version of NI DAQ Traditional NI DAQ Legacy has the same VIs and functions and works the same way as NI DAQ 6 9 x You can use both Traditional NI DAQ Legacy and NI DAQmx on...

Page 100: ...nts typically used with a PC that has the functionality of a classic stand alone instrument 2 A LabVIEW software module VI which consists of a front panel user interface and a block diagram program VI...

Page 101: ...calibration certificate NI resources C 2 conventions ix correlated DIO DI Sample Clock 4 4 digital waveform acquisition 4 3 digital waveform generation 4 2 DO Sample Clock 4 2 counter applications 5...

Page 102: ...ure 2 4 NI 6723 figure 2 5 NI 6731 figure 2 2 NI 6733 figure 2 3 NI DAQCard 6715 figure 2 3 signal descriptions 2 9 I O protection 4 5 instrument drivers NI resources C 1 interrupt request IRQ 9 2 int...

Page 103: ...n 3 3 related documentation x RTSI 8 1 S signal descriptions 2 9 software NI resources C 1 support technical C 1 synchronizing multiple devices 8 4 T technical support xv C 1 terminal name equivalents...

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