NI-DAQmx Base 2.0 Readme

Copyright 2005 National Instruments. Part number 371034A-01. All rights reserved. For patents covering National Instruments products, refer to ni.com/patents.

CVI™, LabVIEW™, Measurement Studio™, National Instruments™, NI™, ni.com™, and NI-DAQ™ are trademarks of National Instruments Corporation.

Product and company names mentioned herein are trademarks or trade names of their respective companies.

Thank you for using NI-DAQmx Base 2.0.

The NI-DAQmx Base 2.0 software contains LabVIEW and C Application Programming Interfaces (API) that allow you to create applications for your device.

NI-DAQmx Base 2.0 supports:

• USB-92xx, USB-600x, and USB-6501 devices on Windows 2000/XP
• NI PCMCIA E Series cards and the NI CF-6004 on Pocket PC 2003 with LabVIEW 8.0 PDA Module
• NI M Series and NI 671x and NI 673x devices on Ardence RTX with LabVIEW Real-Time for RTX 8.0

The Readme contains the following main sections:

• Choosing the API to Use
• Support in NI-DAQmx Base 2.0
• Device Support
• Known Issues
• Error Codes

Choosing the API to Use

The following sections provide a NI-DAQmx and NI-DAQmx Base 2.0 overview and include information about choosing the right API for the device and application.

NI-DAQmx

NI-DAQmx is the latest NI-DAQ driver with new VIs and functions and development tools for programming measurement devices. Install and use NI-DAQmx if the following situations apply:

• You are using Windows 2000/NT/XP
• You are using only device(s) supported by NI-DAQmx. If you are using NI application software, you must use LabVIEW, LabWindows/CVI, or Measurement Studio version 7.x, or LabVIEW with the LabVIEW Real-Time Module 7.1 to use NI-DAQmx
• If you use one of the Measurement Studio .NET languages or a device supported by NI-DAQmx, you must use NI-DAQmx

NI-DAQmx Base 2.0

Install and use NI-DAQmx Base 2.0 if the following situations apply:

• You are using an operating system not supported by NI-DAQmx, such as Linux or MacOS X
• You are using a device which is only supported by NI-DAQmx Base 2.0

NI-DAQmx Base 1.5.1 for RTX

Install and use NI-DAQmx Base 1.5.1 for RTX if the following situations apply:

• You are developing a DAQ application for Ardence RTX with the LabVIEW 7.1 Real-Time Module for RTX and M Series or NI 671x/673x devices.

NI-DAQmx Base 1.0.x

Install and use NI-DAQmx Base 1.0.x if the following situations apply:

• You are developing a DAQ application for PocketPC 2003 with LabVIEW 7.1 PDA, E Series devices, or NI CF-6004

Support in NI-DAQmx Base 2.0

Application Software and Programming Language Support

The following table lists the application software versions supported by NI-DAQmx Base 1.0.2.

The following table lists the language versions supported by NI-DAQmx Base 2.0.

Device Support

Device support is divided into the following categories:

• Devices Supported by NI-DAQmx Base 2.0 for PocketPC (LabVIEW PDA 8.0)
• Devices Supported by NI-DAQmx Base 2.0 for RTX (LabVIEW Real-Time 8.0)
• Devices Supported by NI-DAQmx Base 2.0 for Windows

Devices Supported by NI-DAQmx Base 2.0 for PocketPC:

• NI DAQCard 6024E 200 kS/s, 12-bit, 16 AI channels, two AO channels, 8 DIO lines, two counter/timers
• NI DAQCard 6062E 500 kS/s, 12-bit, 16 AI channels, two AO channels, 8 DIO lines, two counter/timers
• NI DAQCard 6036E 200 kS/s, 16-bit, 16 AI channels, two AO channels, 8 DIO lines, two counter/timers
• NI DAQCard AI-16E-4 (6041E) 500 kS/s, 12-bit, 16 AI channels, 8 DIO lines, two counter/timers
• NI CF-6004 200kS/s, 14-bit, 4 AI channels, 4 DIO lines

Devices Supported by NI-DAQmx Base 2.0 for RTX

• NI PCI-6220 16 AI channel, 250 kS/s, 16-bit M Series device
• NI PCI-6221 16 AI channel, 250 kS/s, 16-bit M Series device
• NI PCI-6224 32 AI channel, 250 kS/s, 16-bit M Series device
• NI PCI-6225 80 AI channel M Series device
• NI PCI-6229 32 AI channel, 250 kS/s, 16-bit M Series device
• NI PCI-6250 16 AI channel, 1 MS/s, 16-bit M Series device
• NI PCI-6251 16 AI channel, 1 MS/s, 16-bit M Series device
• NI PCI-6254 32 AI channel, 1 MS/s, 16-bit M Series device
• NI PCI-6259 32 AI channel, 1 MS/s, 16-bit M Series device
• NI PCI-6280 16 AI channel, 500 kS/s, 18-bit M Series device
• NI PCI-6281 16 AI channel, 500 kS/s, 18-bit M Series device
• NI PCI-6284 32 AI channel, 500 kS/s, 18-bit M Series device
• NI PCI-6289 32 AI channel, 500 kS/s, 18-bit M Series device
• NI PCI-6711 1 MS/s, 12-bit, 4 channel AO device
• NI PCI-6713 1 MS/s, 12-bit, 8 channel AO device
• NI PCI-6731 1 MS/s, 16-bit, 4 channel AO device
• NI PCI-6733 1 MS/s, 16-bit, 8 channel AO device

Devices Supported by NI-DAQmx Base 2.0 for Windows

• NI USB-9211 4 AI Channels, 24-bit thermocouple input module
• NI USB-9215 4 AI Channels, ±10 VDC, 16-bit simultaneous sampling analog input module
• NI USB-6008 12-bit, 10 kS/s, 8 AI channel, 12 DIO line, 1 event counter device
• NI USB-6009 14-bit, 48 kS/s, 8 AI channel, 12 DIO line, 1 event counter device
• NI USB-6501 24 DIO line, 1 event counter device

Operating System Requirements

The following section discusses NI-DAQmx Base 2.0 operating system installation requirements. When installing NI-DAQmx Base, the development operating system must meet the following requirements:

Windows

NI-DAQmx Base 2.0 Known Issues

The following list covers issues specific to NI-DAQmx Base 2.0.

• PDA Support
• RTX Support
• USB Support
• Miscellaneous

PDA Support

• Before installing the NI-DAQmx Base 2.0 Pocket PC components, remove any existing NI-DAQmx Base 1.0 or 1.0.1 installation from the device. To remove from the host, open ActiveSync and select Add/Remove Programs... from the Tools menu. To remove from the device (Pocket PC) go to Start >> Settings, click on the System tab and select Remove Programs.
• NI-DAQmx Base 2.0 provides example tasks for both the E Series and CF-6004 DAQ devices. To switch between the two task lists, select Import Tasks List in the NI-DAQmx Base Task Configuration Utility. Select the tasks list from C:\Program Files\National Instruments\LabVIEW 7.1|8.0\examples\daqmxbase directory. The following examples work for the CF DAQ-6004:
  • Acq&Graph Voltage-Int Clk.vi
  • Cont Acq&Graph Voltage-Int Clk.vi
  • Cont Acq&Graph Multiple Voltages-Int Clk.vi
  • Acq&Graph Voltage-Raw I16-Int Clk.vi
  • Acq&Graph Voltage-Int Clk-Dig Start.vi
  • Read Dig Port.vi
  • Write Dig Port.vi
• In the LabVIEW development environment, you cannot browse for tasks configured in the DAQmx Base Configuration Utility. You must type a task name in the LabVIEW DAQmx Task Name Constant control/constant field on the development machine.
• Some E Series devices on some PDAs may experience problems loading the calibration constants. If this condition is detected, a warning (223700) is generated by the start task VI. This condition has been reported on the Compaq IPAQ 3900 series.
• The DAQ hardware model (such as 6062E or 6036E) is not detected at run-time on the PDA. The driver determines the DAQ device capabilities, scaling mode, and calibration constants based on the DAQ hardware model selected in the NI-DAQmx Base Configuration Utility.
• Single-point analog input (AI) is not supported. All the DAQ devices supported in this release support buffered AI tasks.
• Triggering (digital or analog) is supported only for analog input tasks.
• Only the DAQCard-6062E supports buffered AO operations. AO tasks do not work for any other DAQ device. If an AO task is used with a non-supported device, the write operation times out (error -200474) when it tries to writes to the FIFO.
• The first sample of an analog output task, without FIFO regeneration enabled, is not generated.
• PFI 0 is the only supported analog trigger signal input on E Series devices.
• DAQ Task constants might lose their value when building an application. When using DAQ Task constants, use Operate»Make Current Value Default, with the block diagram open to set the string value to the DAQ Task constant before building an application. When using this method, the constant does not lose its value after the application is deployed.
• Due to the limited processing capabilities of PDA devices, the maximum buffered counter read rate is 4 Hz. This read rate refers to the rate at which counter measurements are triggered. This limitation does not apply to more common read operations.
• The first reading in pulse width and period measurement counter operations is discarded. Two consecutive pulses are needed to take a measurement; the returned measurement refers to the last pulse.
• NI-DAQmx Base 2.0 for PDA supports static task configuration only. Programmatic task configuration might be supported in a future version of NI-DAQmx Base.
• Saving VIs while building an NI-DAQmx Base application might take longer than saving all VIs needed to build a non-NI-DAQmx Base application. NI-DAQmx Base might have more than 100 VIs in memory, which increases the time required to save VIs for the Build for PDA process.
• Property nodes are not available in LabVIEW PDA, including NI-DAQmx API properties. NI-DAQmx API properties are not supported in NI-DAQmx Base 2.0 Use the NI-DAQmx Base Task Configuration Utility to change parameters not supported in the VIs.
• For faster acquisitions, set Generate Serial Only in the Application Build Specification. Generate Serial Only increases the maximum speed of NI-DAQmx Base 2.0 by disabling the pauses which update the VI front panel during execution. If you select Generate Serial Only, you must add a 10 ms wait in the main loop of the VI, otherwise the VI might appear unresponsive.
• For the fastest AI acquisitions, use the Raw I16 1D version of the polymorphic DAQmxBase Read.vi. The Raw I16 1D version allows the least amount of memory allocation and no floating point calculations.
• Changing the system font or Windows color schemes can cause incorrect behavior in E Series AI Read FIFO Raw 1D I16 Pretrigger.vi and E Series AI Read FIFO Raw 1D I16.vi. This incorrect behavior might cause the following run-time error in the PDA application: Error code 130413003: Unable to lock memory chunk. To fix this error, open the VI and click the run arrow while pressing the <Shift> key. Doing so forces a recompile of the VI, which should fix the error.

RTX Support

• Hardware installation issues

To avoid device enumeration conflicts with NI-DAQmx, NI-DAQmx Base does not install a Windows inf file to identify DAQ devices. If you do not have NI-DAQmx installed and need to identify your DAQ devices before swiching to RTX, install the dmxbase.inf file included in 'C:\RTXRoot\ni-rt\system\inf' by copying it to the WINDOWS\inf directory. The Windows inf directory is hidden by default on most systems.

Refer to 'RTX Documentation Library >> RTX Runtime Documentation >> Managing Devices' for details on how to convert a Windows device to a RTX device.

RTX devices that use interrupts cannot share interrupts with Windows devices. This may require some modifications to the device resources to force exclusive access to an IRQ line. In NI-DAQmx Base, a device works correctly without exclusive access to an IRQ line as long as the device does not use interrupts. Only M Series AI tasks that use the 'Wait for Next Sample Clock.vi' generates and uses interrupts.

• Wait For Next Sample Clock.vi 'late' detection

'Wait for Next Sample Clock.vi' may not detect a late acquisition if the VI is running in time-critical priority. A real-time priority thread preempts the interrupt queue mechanism used to detect interrupts.

Set the VI priority to 'high priority' to allow the queue mechanism to detect interrupts or use the read VI warning to detect if your acquisition loop is not keeping up with the hardware.

• RT Target communication timeout during download

LabVIEW Real-Time may briefly lose communication with the RTX target while the DAQmx Base VIs are downloaded and setup to run. The LabVIEW host displays a timeout message box that disappears once communication is re-established.

• NI-DAQmx Base Configuration Tool

Static tasks and the NI-DAQmx Base Configuration Utility are not supported for RTX.

USB Support

• Launching the NI-DAQmx Base Configuration Tool While a Task is Running

Do not launch the NI-DAQmx Base Configuration Utility while an acquisition task is in progress as this might cause the running task to hang.

• Using Multiple USB Devices

You can use multiple USB devices concurrently, providing that they are accessed from within the same process.

• Hotplug USB Support

If a USB device is added or removed, you must update the device list either by selecting Refresh Device in the NI-DAQmx Base Configuration Utility or by launching (or re-launching) LabVIEW prior to using the device. Note that updating the device list might change the device order (such as, "Dev1" becomes "Dev2").

• USB-9215 Maximum Sample Rate

The USB-9215 maximum sample rate is determined by the highest channel number read, not by the number of channels read.

Highest Channel Number	Maximum Sample Rate
0	20 kS/sec
1	10 kS/sec
2	6.67 kS/sec
3	5 kS/sec

• USB-6009 Aggregate Scan Rates

When sampling more than 2 channels, the maximum aggregate scan rate is determined by the number of channels.

Number of Channels	Maximum Aggregate Sample Rate
1	48 kS/sec
2	48 kS/sec
3	45.5 kS/sec
4	44 kS/sec
5	43.5 kS/sec
6	43 kS/sec
7	42 kS/sec
8	40.5 kS/sec

• USB-9211 Sample Process

When performing a thermocouple task, the USB-9211 automatically reads both the Cold-Junction and Autozero channels and uses these values when calculating the temperature every time the scan list is sampled. Both reads count towards the overall sample rate. Thus the effective maximum sample rate for thermocouple tasks is 12/(N+2) S/sec where N equals the number of channels being read. For example, if three channels are being read by a thermocouple task, the maximum sample rate is then 12/(3 + 2) = 2.4 S/sec. Higher sample rates might be obtained by reading the desired thermocouple channel as a voltage channel in an Analog Input task. However, as an Analog Input task, the resulting units are volts, and temperature calculation is not performed by the driver.

The Cold-Junction Compensation sensor can be read by using physical channel 4 as a voltage channel. The Autozero channel is not available as a physical channel.

• USB-92xx LED Might Blink Sporadically

The USB-92xx LED might not blink at a steady rate when acquiring data. Sporadic blinking is normal and does not affect data acquisition.

• USB Devices Might not be Available After Hibernation

After resuming from hibernation, USB devices might not register in NI-DAQmx Base. Physically re-inserting the USB devices or refreshing the Windows Device Manager allows NI-DAQmx Base to detect the USB devices again.

• USB-9211 and USB-9215 Channel Voltage Range

The USB-9211 and USB-9215 devices do not provide a user-configurable channel range. The following lists the supported channel ranges per device:

USB-9211	±80 mV
USB-9215	±10 V

• Building C Examples with Visual Studio .NET

To build DAQmx Base examples in Visual Studio.NET, complete the following steps:
1. Launch Start »Program Files»Microsoft Visual Studio .Net 2003»Visual Studio .Net Tools»Visual Studio .NET 2003 Command Prompt
2. Type ">cd C:\Program Files\National Instruments\NI-DAQmx Base\Examples"
3. Select the example type: ai, ao, ctr, or dio
4. Type ">nmake examplename.mak"

Miscellaneous

• ESeries minimum sample rate is 1.2 Hz. NI-DAQmx Base only uses the 20MHz clock and ESeries devices have 24 bit counters, which limits the minimum sample rate to 1.2Hz (20MHz / 2²⁴). For lower sample rates the timebase divisor will overflow 2²⁴. When this value is loaded into the 24 bit counter, only the lower 24 bits are used resulting in a much faster sampling rate than expected.
• Some VIs may be marked as dirty when opened in different contexts (Windows, PocketPC or RTX). LabVIEW will prompt to save the VIs before deployment.
• When a new device is added or removed, you should run Start » Programs » National Instruments » NI-DAQmx Base » List Devices.
  
  Make note of the device name (such as, Dev1) as this is the name you need to specify when creating channels in the program. A device name might change each time a device is added or removed.
• To use static tasks created with the NI-DAQmx Base Configuration Utility, type the desired task name into the Task Constant or Task Control.
  
  When using any NI-DAQmx Base control from the control palette, make sure the Allow Undefined Names attribute is enabled. To enable the Allow Undefined Names attribute, right-click on the control and select I/O Name Filtering. Place a checkmark in the Allow Undefined Names checkbox and click OK.
• The NI-DAQmx Base installer does not overwrite existing task configuration files. To restore the task list to the default tasks, import the configuration file installed in the static example directory.
• Using DAQmxBase CreateTask, DAQmxBase Create Virtual Channel, and DAQmxBase Clear Task in a loop leaks approximately 110 bytes per iteration. If you pass in a string for the taskName parameter in DAQmxBase Create Task, the memory leak does not occur.
• If, when building an executable or shared object project using NI-DAQmx Base VIs, the Application Builder catches an error, you must restart LabVIEW before running any NI-DAQmx Base VI.
• DAQmxBaseIsTaskDone and DAQmxBase Is Task Done do not currently support analog input.
• If your machine enters Hibernate/Sleep, restart your C or LabVIEW-built application, or LabVIEW to properly communicate with your DAQ device.

NI-DAQmx Base 2.0 Error Codes

The following is a list of supported error codes in the NI-DAQmx Base 2.0 API.

• -223700 Internal software error.
• -200797 An empty string was specified as a terminal name which is not supported. Specify a valid terminal name.
• -200745 Frequency and Initial Delay property values are inconsistent with one or more counter timebase properties. The conflicting properties must satisfy the following constraints:

  Counter Timebase Rate / Counter Maximum Count <= Frequency <= Counter Timebase Rate / 4

  Counter Timebase Rate / Counter Maximum Count <= 1 / Initial Delay <= Counter Timebase Rate / 2

  If the Counter Timebase Rate is not specified, it is inferred from the Counter Timebase Source selection.

• -200714 Acquisition has stopped because the driver could not transfer the data from the device to the computer memory fast enough. This was caused by computer system limitations Reduce your sample clock rate the number of channels in the task or the number of programs your computer is executing concurrently.
• -200608 Acquisition cannot be started, because the selected buffer size is too small. Increase the buffer size.
• -200565 Specified digital channel contains more bits than supported by the 8-bit version of DAQmxBase Port Write. Use the version of DAQmxBase Port Write that supports wider digital ports.
• -200564 Specified digital channel contains more bits than supported by the 32-bit version of DAQmxBase Port Read.
• -200561 Attempted writing analog data that is too large or too small.
• -200559 Task cannot contain a channel with the specified channel type, because the task already contains channels with a different channel type. Create one task for each channel type.
• -200558 One task cannot contain multiple independent devices. Create one task for each independent device.
• -200552 Specified string is not valid, because it contains an invalid character.
• -200536 Specified value is smaller than the minimum value supported for this property.
• -200527 Requested values of the Minimum and Maximum properties for the counter channel are not supported for the given type of device. The values that can be specified for Minimum and Maximum depend on the counter timebase rate.
• -200526 Write cannot be performed because this version of DAQmxBase Write does not match the type of channels in the task. Use the version of DAQmxBase Write that corresponds to the channel type.
• -200525 Read cannot be performed because this version of DAQmxBase Read does not match the type of channels in the task. Use the version of DAQmxBase Read that corresponds to the channel type.
• -200524 Write cannot be performed, because the data does not contain data for all channels in the task. When writing, supply data for all channels in the task. Alternatively, modify the task to contain the same number of channels as the data written.
• -200523 Read cannot be performed because this version of DAQmxBase Read only returns data from a single channel, and there are multiple channels in the task. Use the multichannel version of DAQmxBase Read.
• -200498 Syntax for a range of objects in the input string is invalid. For ranges of objects, specify a number immediately before and after every colon (":") in the input string. Or, if a name is specified after the colon, it must be identical to the name specified immediately before the colon. Colons are not allowed within the names of the individual objects.
• -200489 Specified channel cannot be added to the task, because a channel with the same name is already in the task.
• -200485 The specified task cannot be loaded, because it is not a valid task.
• -200478 Specified operation cannot be performed when there are no channels in the task.
• -200474 Specified operation did not complete, because the specified timeout expired.
• -200473 Read cannot be performed when the Auto Start property is false and the task is not running or committed.
• -200459 Write failed, because there are no output channels in this task to which data can be written.
• -200452 Specified property is not supported by the device or is not applicable to the task.
• -200430 I/O type of the physical channel does not match the I/O type required for the virtual channel you are creating.
• -200428 Value passed to the Task/Channels In control is invalid. The value must refer to a valid task or valid virtual channels.
• -200361 Onboard device memory overflow. Because of system and/or bus-bandwidth limitations, the driver could not read data from the device fast enough to keep up with the device throughput. Reduce the sample rate, or reduce the number of programs your computer is executing concurrently.
• -200341 Generation was configured to use only onboard memory, but the corresponding buffer is larger than onboard memory. Buffer size is provided implicitly when data is written or explicitly when the buffer is configured.
• -200330 An attempt has been made to use the PFI0 terminal of the device for both an analog and digital source. Use a terminal other than PFI0 as the source of your digital signal.
• -200326 An attempt has been made to perform a route when the source and the destination are the same terminal. In many cases, such as when configuring an external clock or a counter source, you must select a PFI, PXI Trigger, or RTSI line as the source terminal.
• -200287 Attempted to write to an invalid combination of position and offset. The position and offset specified a sample prior to the first sample generated (sample 0). Make sure any negative write offset specified selects a valid sample when combined with the write position.
• -200284 Some or all of the samples requested have not yet been acquired. To wait for the samples to become available use a longer read timeout or read later in your program. To make the samples available sooner, increase the sample rate. If your task uses a start trigger, make sure that your start trigger is configured correctly. It is also possible that you configured the task for external timing, and no clock was supplied. If this is the case, supply an external clock.
• -200278 Attempted to read a sample beyond the final sample acquired. The acquisition has stopped, therefore the sample specified by the combination of position and offset will never be available. Specify a position and offset which selects a sample up to, but not beyond, the final sample acquired. The final sample acquired can be determined by querying the total samples acquired after an acquisition has stopped.
• -200265 An attempt has been made to use an invalid analog trigger source. If you explicitly named the virtual channel using DAQmxBase Create Channel, you must use the name assigned to that channel.
• -200261 An attempt has been made to use an analog trigger in multiple situations with differing properties. Change the analog trigger properties so they are the same, or do not use an analog trigger for all situations.
• -200254 Terminal for the device is invalid.
• -200220 Device identifier is invalid.
• -200214 Analog trigger circuitry unavailable on the device. Select a non-analog trigger type, or use a device with analog triggering hardware.
• -200170 Physical channel specified does not exist on this device. Refer to the documentation for channels available on this device.
• -200099 Physical channel not specified.
• -200096 Number of samples to read must be -1 or greater.
• -200089 Task name specified conflicts with an existing task name.
• -200082 Minimum is greater than or equal to the maximum.
• -200077 Requested value is not a supported value for this property.
• -200040 Source terminal to be routed could not be found on the device. Make sure the terminal name is valid for the specified device. Refer to help for valid terminal names.
• -200012 Specified physical channel does not support digital output.
• -89136 Specified route cannot be satisfied, because the hardware does not support it.
• -89131 An attempt has been made to perform a route when the source and the destination are the same terminal. In many cases, such as when configuring an external clock or a counter source, you must select a PFI, PXI Trigger, or RTSI line as the source terminal.
• -89120 Source terminal to be routed could not be found on the device. Make sure the terminal name is valid for the specified device.
• -50256 USB Device error: Feature not supported.

  NI-DAQmx Base 1.5.1 Warning Codes

• 209800 DAQmxBase Read did not complete before the arrival of the next sample clock which indicates that your program is not keeping up with the hardware clock. For tasks using sample clock timing slow down the hardware clock or else change your application so that it can keep up with the hardware clock.
• 209802 DAQmxBase Wait for Next Sample Clock detected one or more missed sample clocks since the last call to Wait for Next Sample Clock which indicates that your program is not keeping up with the sample clock. To remove this warning slow down the sample clock or else change your application so that it can keep up with the sample clock.
• 233700 Internal software warning.

MHDDK Error Code

• 15 Resource Not Found - The application cannot get access to the hardware. Occurs if the DAQ device is not installed on the PDA or the reference to the hardware is invalid. For an invalid reference, restart LabVIEW.