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RPvdsEx Tech Notes

Help links don't work in Adobe Reader DC 2020

TN2001

Product: Synapse, RPvdsEx
Version: 94
Date Added: 2020-02-19

Issue

When clicking on the help link in Synapse, or for an RPvdsEx component, the PDF manual opens but does not jump to the correct page. This is observed with Adobe Reader DC 2020 only.

Workaround

Download the latest TDTToolBox.dll, copy it into C:\TDT\lib and C:\TDT\Synapse (if using Synapse), replacing the file that is there.

Solution

Upgrade to the latest version of Synapse.

RS4 High Channel Count Streaming

TN0989

Product: RS4, Synapse, RPvdsEx
Version: 90
Date Added: 2018-10-15

Issue

Improvements to the RS4 firmware have improved stability when streaming high channel count data to multiple ports on the RS4. This requires updates to the software (Synapse and RPvdsEx macros) and RS4 firmware.

Solution

Users streaming high channel count data to multiple RS4 ports require an additional setting. The "Use Larger Buffer Size" option allows more DSP memory to hold the data destined for the RS4, which improves reliability during the data transfer. The RS4 must be updated to v1.19 firmware to most effectively use this setting (more on that below).

In Synapse, this option is in the RS4 options:

If using OpenEx, this option is in the v90 Stream_Server_MC macro In RPvdsEx:

RS4 v1.19 Firmware Update:

It is recommended that all RS4 users update to the latest RS4 firmware. With the RS4 connected to the internet, go to the Config tab and select "Update Firmware". The updates are incremental, so you may need to repeat this step several times until the version number at the top of the Ports tab says "v1.19".

In v1.19, the RS4 saves a log text file within each recording folder that tracks the starting and ending sample of each stream. It also makes audible beeps when a recording starts and stops, or if there is a transfer error during the recording.If there is a gap in the saved data stream (typically this would be caused by a physical problem with the fiber optic connection between the RZ2 and RS4), this will also be indicated in the log file, so the data can be aligned in post processing. If the gap is long enough, the RS4 will assume the recording has stopped and start new files when data comes in. This allowable gap is controlled by the "Rec Stop Timeout" setting on the Config tab Settings.

Normalize speaker output, using an FIR filter in an RPvdsEx circuit created in Matlab

TN0966

Product: RPvdsEx, SigCalRP
Version: All
Date Added: 2014-12-16

Issue

This article explains how to use SigCalRP and Matlab to generate FIR coefficients, then use them in RPvdsEx to filter signals that will be played out to a speaker.

To generate your coefficients follow these three steps:

  1. Use SigCalRP to measure the transfer function (TF) of the system.

  2. Export calibration data in CSV format.

  3. Use a Matlab script to convert the CSV file into a set of filter coefficients.

The FIR coefficients generated in this example, can be used to filter signals of varying frequency and constant amplitude so that the sound output in units of dB SPL from the speaker will be constant over all frequencies. These coefficients will be generated for a circuit running at a specific sampling frequency. To work properly, they must be used in a circuit running at the same sampling frequency.

Measuring the TF of the system

SigCalRP can be used to calculate the TF of a system for speaker calibration at sample rates up to 200 kHz. Before performing this operation, users should know the A/D and D/A conversion limitations of their specific hardware. For example, the RZ6 maximum sampling rate is 195312.50 for both signal production and acquisition. The figure below shows a typical setup using a single RZ6.

Under Signal Setup in SigCalRP, enter the frequency step using the number of frequencies you wish to measure across the spectrum and the Nyquist frequency. For an RZ6 running at 200 KHz and a filter of 200 points, the Nyquist frequency is 97656.25 Hz and the frequency start and frequency step are determined by the relationship:

97656.25/200 = 488.28125 Hz

Run SigCalRP at 200 kHz to ensure that the Nyquist frequency of the device running the FIR (97656.25 Hz) is represented. Also, make sure that all test frequencies used are integer multiples of the Nyquist frequency of the device to avoid aliasing.

Set the horizontal green bar in the calibration plot to the dB level you want to achieve for all frequencies using the filter. The filter will attenuate frequencies above the green bar and amplify frequencies below it. Use care when amplifying the signal. Typically, only frequencies that will not be presented should be amplified.

To export the data as a *.csv file, select Export Calibration Data on the Calibrate menu.

Creating the filter coefficients

Next, download and extract the compressed (.zip) SigCalRP Example files from the TDT website at SigCalRPExamples.zip.

Use the provided Matlab script (RZ6SigCalFIR.m) to convert the CSV file into a set of FIR coefficients. Your output will be a .txt file that can be used with RPvdsEx.

Loading the filter coefficients

Add FIR and SourceFile components to the signal generation segment of your RPvdsEx circuit as shown below.

Update the SourceFile component to point to the .txt file generated by the Matlab script. Any signal that passes through that FIR component will be normalized.

A sample CSV file and several circuit files are included in the Example folder for demonstration purposes.

Known Third Party Software Conflicts

TN0937

Product: OpenEx, RPvdsEx, Synapse
Version: All
Date Added: 2014-08-15

Issue

Some programs that make background memory calls on a PC create fatal errors and force TDT software, such as OpenEx or RPvdsEx, to shutdown.

Error Message: The TDT application may or may not give an error message, such as: The RPC server is unavailable.

Problem Behavior: Software crashes.

Known program conflicts:

  1. HP Security Manager (Tech Note #0908)

  2. CrashPlan Backup Software on Windows 7

  3. Dell Data Protection

Solution

Remove or disable the software causing the conflict.

The Microsoft Process Explorer (found here: http://technet.microsoft.com/en-us/sysinternals/bb896653.aspx) can be a useful tool for determining the source of the conflict.

PZ5 Scaling Issues with RZ2_Input_MC

TN0926

Product: RPvdsEx, PZ5
Version: All
Date Added: 2013-09-17

Issue

When using the RZ2_Input_MC macro with the PZ5, you must scale the signals.

Workaround

Use an MCScale component to multiply the signals by 4.

RPvdsEx Title Bar Disappears in Windows 7

TN0925

Product: RPvdsEx
Version: All
Date Added: 2013-06-25

Issue

When using Windows 7, some combinations of actions (opening, closing, minimizing, and maximizing windows or files) cause the RPvdsEx Title Bar to disappear or toolbars to be displayed incorrectly.

Workaround

The display can typically be corrected by clicking a different tab in the RPvdsEx tabbed window.

Solution

To avoid this problem, right-click the Windows taskbar and click Properties. In the Taskbar buttons drop-down list, select Never combine.

Schmitt2 component output stays high

TN0913

Product: RPvdsEx
Version: All
Date Added: 2013-01-17

Issue

The minimum allowed value of the Schmitt2 component's nHi input is 1. However, using a parameter tag or signal line, the value of nHi can be forced to 0. If the Schmitt2 is triggered while nHi is 0, the output will go high and stay high until the circuit is restarted.

Solution

Do not set nHi to 0; this will not disable output of the Schmitt2. If you wish to disable output of the Schmitt2, set the Schmitt2 component's nEnab input low.

EdgeDetect erroneous output on first sample

TN0910

Product: RPvdsEx
Version: All
Date Added: 2012-11-29

Issue

The EdgeDetect component outputs a one sample TTL pulse when the input changes states. At start up, the 'previous state' is initialized incorrectly which can cause the component to send a false trigger at start up under the following conditions:

  1. Edge=Falling and initial input is 0.

  2. Edge=Rising and initial input is 1.

Workaround

The circuit below uses a Not and OneShot component to ensure the output during the first sample is 0. If you have multiple EdgeDetect components in your circuit, you can reduce your component count by using the EDEnab hop.

RPvdsEx crashes when used with OpenEx

TN0908

Product: OpenEx, RPvdsEx
Version: All
Date Added: 2012-10-16

Issue

Some security programs confuse third-party software background memory calls with fatal errors and force shutdown the program either without giving an error message or giving the message "The RPC server is unavailable."

On some, but not all HP computers, the HP Security Manager will allow RPvdsEx to work without error in standalone mode but will not allow circuits to open when RPvdsEx is attached to OpenEx. Microsoft support has identified this issue and offered the following solution.

Solution

To resolve this issue, you must disable a DLL for the HP Security Manager. To do this:

  1. Browse to C:\Program Files (x86)\Hewlett-Packard\HP ProtectTools Security Manager\Bin.

  2. Locate the DpFbView.dll file and rename the file, changing the extension from .dll to .old.

RPvdsEx component Help button not working

TN0906

Product: RPvdsEx
Version: All
Date Added: 2012-09-13

Issue

The context sensitive help for components in RPvdsEx may not link correctly to the RPvdsEx Manual.

Solution

Upgrade to the latest version of Adobe Reader and ensure it is being used to open PDF files. If you have Adobe Acrobat Standard or Professional, ensure these programs are NOT used to open the manual.

Channels doubled when using MCSerSource

TN0898

Product: RPvdsEX
Version: 74
Date Added: 2008-03-17

Issue

When using MCSerSource, channels are doubled, so that channel N+1 clones channel N where N is an odd number (i.e. Chan 2 is a clone of Chan 1, Chan 4 is a clone of Chan 3, etc).

Solution

Upgrade to the latest version of TDT drivers and microcode. This issue was resolved in v 82.

RZ2 input sometimes produces NaNs

TN0886

Product: RZ2, RPvdsEx
Version: TDT Drivers < 72
Date Added: 2010-12-17

Issue

On rare occasions, the data pipe on the RZ2 outputs a NaN ("Not a Number"). This breaks any floating-point math that is applied to the signal, which results in garbage data or a flat line. This is most likely to occur at startup, if your circuit uses many SourceFile components.

Workaround

Add an MCBound component to the output of RZ2_Input_MC. This component will replace NaNs with zeros.

Solution

Upgrade to latest version of TDT Drivers/RPvdsEx. The RZ2_Input_MC macro has been updated to handle NaNs.

Store Pooling does not work correctly with Slow_Store_MC macro

TN0882

Product: OpenEx, RPvdsEx
Version: < 72
Date Added: 2010-10-15

Issue

When using Store Pooling with the Slow_Store_MC macro, channels of the higher pool members will be identical to the lower pool members.

Solution

Upgrade to the latest version of TDT Drivers and OpenEx. This issue was resolved in version 72.

Erroneous 2-sample delay in Epoc_Store_With_Offset timestamp

TN0877

Product: OpenEx, RPvdsEx
Version: < 72
Date Added: 2010-10-07

Issue

When using the Epoc_Store_With_Offset macro, the onset timestamp is delayed by two samples. This can cause the onset to appear to have occurred two samples before it actually did and will not by synchronized with other Epoc_Stores in the circuit.

Solution

Upgrade to the latest version of TDT Drivers and OpenEx. This issue was resolved in v72.

Setting arbitrary sample rates for the RX8

TN0870

Product: RPvdsEx
Version: All
Date Added: 2010-03-23

Issue

When using the Check Realizable feature to set an arbitrary sampling rate for the RX8, RPvdsEx calculates rates for PCM converters. However, the RX8 may also be equipped with Sigma-Delta converters. If a PCM rate is used for an RX8 equipped with Sigma-Delta converters, signals will be distorted producing either a flat-line signal or signal drift (if the rates are close).

Workaround

The circuit will work correctly if the correct realizable rate is entered for the type of converters equipped on your RX8. A table of realizable rates supported for the Sigma-Delta converters is available in the System 3 manual. Simply look up the rate and enter it in the RPvdsEx hardware setup dialog.

If you do not wish to enter the value manually you can use the following method

In RPvdsEx, the RX6 arbitrary sample rates are calculated based on supported sigma-delta rates. Select the RX6 Multi-Function processor and enter your arbitrary sample rate. Click the Check Realizable button to approximate the supported sigma-delta sample rate. Finally, select the RX8 Multi I/O processor and click OK. Note that the RX8 supports a maximum sampling rate of 100 kHz.

This will ensure that your arbitrary sample rate is supported by the sigma-delta converters.

UDP interface is unable to send packets

TN0864

Product: RZ-UDP, RPvdsEx
Version: 1.2
Date Added: 2009-09-28

Issue

When using the RZ_UDP_Send macro, the UDP interface is unable to send packets.

Solution

Update to the latest version of the RZ UDP Utility.

The SampSubtract component does not work correctly

TN0856

Product: RPvdsEx
Version: > 5.2
Date Added: 2009-06-02

Issue

When running a circuit containing the SampSubtract component on any single-DSP device (RP2.1, RA16, etc.) the SampSubtract component does not work correctly (the buffer is all zeros and never changes).

Workaround

The SampSubtract component is designed for multi-DSP devices such as the RX5 and RZ2, for single-DSP devices, contact tech support for a possible alternative solution.

MCDacOut component only outputs a single channel

TN0854

Product: RZ, RPvdsEx
Version: All
Date Added: 2009-05-29

Issue

The MCDacOut component only outputs a single channel, the channel defined in the ChanOS parameter.

Workaround

Instead of using the MCDacOut component, an iterate component can be used to create multiple DacOut components conveniently.

In this example, the iterate component will generate 4 separate DacOut components, one for each channel of the multi-channel signal.

PZ3_ChanMap macro causes a warning in RPvdsEx

TN0848

Product: PZ3, RPvdsEx
Version: All
Date Added: 2009-04-09

Issue

When using the PZ3_ChanMap macro in RPvdsEx, the macro causes a warning message to be displayed even when used correctly. The warning message occurs when RPvdsEx detects a channel number mismatch between the RZ2_Input_MC macro and the PZ3_ChanMap macro.

Workaround

The RZ2_Input_MC macro is designed for the PZ2 preamplifier which contains 16 recording channels per bank. The PZ3 amplifier differs in that each bank contains 8 channels for recording and 8 channels for impedance testing. The number of channels parameter defined in the PZ3_ChanMap macro should be configured to output the number of recording channels according to the PZ3. This means that the RZ2_Input_MC macro will have double the number of channels compared to the PZ3_ChanMap macro.

For example, when using a 32-channel PZ3, the PZ3_ChanMap macro channel number parameter would be set to 32 while the RZ2_Input_MC macro channel number would need to be set to 64 (since the PZ3 has half the number of recording channels per bank compared to the PZ2). Refer to the images below for examples of how to correctly use the PZ3_ChanMap macro.

Correct

Incorrect

Ensure that the correct number of channels is set before attempting to use the circuit.

PZ3 unable to record in high input range mode

TN0838

Product: RPvdsEx
Version: 66 and 68
Date Added: 2008-09-08

Issue

Using the PZ3_Control macro to configure the PZ3 amplifier for high input range mode, the amplifier is stuck in impedance checking mode and will not record. Cycling power or pressing the display button to exit impedance checking mode does not solve the problem.

Solution

Upgrade TDT Drivers.

Short(16 bits) Option missing from Stream_Store macros

TN0833

Product: RPvdsEx
Version: 68
Date Added: 2008-07-30

Issue

The range display for the Short(16 bits) store format option is missing on the Stream_Store_1-4Ch, Stream_Store_1-8Ch, and Stream_Store_MC2 stream store macros.

Solution

Upgrade to latest version of TDT Drivers.

RPvdsEx causes Adobe Reader errors

TN0829

Product: RPvdsEx
Version: All
Date Added: 2008-06-27

Issue

When using the RPvdsEx help function with older versions (< version 7) of Adobe Reader, the following error prompts:

Clicking OK opens the RPvdsEx Manual but will not correctly go to the desired component bookmark.

Solution

Update to the latest version of Adobe Reader.

RPvdsEx takes longer than expected to open

TN0827

Product: RPvdsEx
Version: > 65
Date Added: 2008-05-13

Issue

RPvdsEx takes longer than normal (greater than 5 seconds) to open fully and macro property dialog boxes take longer than normal (greater than 2 seconds) to open. This happens if the PC has a problem connecting to the Default Printer specified for the system.

This will often happen with a network printer that is not currently available or has been removed from the network altogether.

Solution

Change the system's Default printer to one that is always available to the PC (e.g. PDF Writer).

WordIn Reports Erroneous Information

TN0269

Product: RPvdsEx
Version: All
Date Added: 2007-10-02

Issue

The WordIn component will give erroneous information when the bit mask is set to values that are outside of the bit range available on the device.

Solution

The WordIn component should be set with a bit mask that corresponds to the physical hardware of the device. First, determine the technical specifications of your device. Once the device's bit range is known, the selectable bit mask range can be determined.

For example, the RP2.1 technical specification states that it has 8 bits of digital I/O, so the maximum range would be

0000 0000 to 1111 1111 or 0 to 255

For more information on using WordIn, see Addressing Digital Bits In a Word.

Unable to use Device Configuration Register for RZ

TN0268

Product: RZ, RPvdsEx
Version: All
Date Added: 2007-10-01

Issue

When an RZ Processor is selected in the Set Hardware Parameters dialog box of RPvdsEx, the Device Configuration Registers section of the dialog box expands but is not editable. Clicking the Clear button produces an error message.

Solution

Use the RZn_Control macro to configure digital I/O for your specific RZ processor.

MCzHopPick not picking the desired channel from a multi-channel signal

TN0263

Product: RPvdsEx
Version: 66
Date Added: 2007-09-13

Issue

When using an MCzHopPick component, some channels may appear to be all zeros, and good data channels may appear shifted to other channels. This issue occurs only with MCzHopPick added using v66 and may be affected by the number zHops (single or multi-channel) used in the circuit.

Solution

Upgrade to the latest TDT Drivers.

StateMachine RPvdsEX component resets unexpectedly

TN0262

Product: RPvdsEx
Version: 66
Date Added: 2007-08-29

Issue

The StateMachine component in RPvdsEX may reset unexpectedly when a circuit is compiled.

Solution

Upgrade to the latest TDT Drivers.

MCSerStore component fails to reset

TN0253

Product: RPvdsEx
Version: 64
Date Added: 2007-05-03

Issue

MCSerStore component will not reset unless both reset (Rst) and enable (WrEnab) are active. Because the Stream_Store_MC2 macro makes use of MCSerStore, it should not be used until this bug is resolved.

Workaround

Use Stream_Store_MC in place of Stream_Store_MC2 where possible. If MCSerStore must be used, ensure both enable and reset are active when reset is needed.

Solution

Upgrade to the latest TDT Drivers.

Tetrode component not supported by classic processors

TN0236

Product: RP, RPvdsEx
Version: All
Date Added: 2007-01-31

Issue

Tetrode is an extended component and is not supported by classic processors.

Solution

The following figure illustrates an alternative circuit design to achieve a signal equivalent to the output of the Tetrode component without using the component itself. This example is for users who wish to achieve the same operation as Tetrode using lower order components on a Classic Processor.

The corresponding voltage threshold for each input channel can be controlled by modifying the Thr# tag value tied to the K parameter of each Compare component.

Build RCO is grayed out in RPvdsEx v60 and greater

TN0226

Product: RPvdsEx
Version: > 59
Date Added: 2006-10-27

Issue

By default, RPvdsEx v60 and greater uses an RCX combined file format instead of the legacy two file system (RPX, RCO). The RCX file format contains both the graphical circuit representation and the control object information. With this preferred file format, the separate control file is no longer needed and the Build RCO button is intentionally grayed out. The RCX file can be opened in RPvdsEx to view or edit the circuit and can also be loaded to a device in the same manner as an RCO file.

To revert to the legacy RPX/RCO file system:

  1. On the Edit menu, click Preferences.

  2. Clear the Embed RCO object file check box.

  3. Click OK.

After performing this step, the Build RCO button is enabled and RCO files can be created as before.

MCFIR, MCFIR2 components produce erroneous results

TN0215

Product: RPvdsEx
Version: 60
Date Added: 2006-09-15

Issue

A memory allocation error in the MCFIR and MCFIR2 components causes erroneous results if the number of channels is set to be greater than the number of taps.

Workaround

A simple workaround to ensure that enough memory is allocated is to specify the nChan parameter to be two greater than the number of channels in the signal. This will cause a channel mismatch between the MCFIR or MCFIR2 component and the components linked to it, but the warning can be ignored.

Solution

Upgrade to the latest TDT Drivers.

FindFreq component returns an incorrect value with low frequency input signals

TN0187

Product: RPvdsEx
Version: All
Date Added: 2005-06-08

Issue

If the input frequency to a FindFreq component is zero, FindFreq will return either an erroneous value or the last valid input frequency. For input signals with a frequency less than 0.1 Hz, the component takes longer to stabilize (~10 seconds).

Workaround

When using low frequency inputs to FindFreq, do not use the output as an input to another circuit component if this transient behavior will affect the operation of the circuit. This component can always be used to troubleshoot circuits.

Circuit fails to acquire or play out filtered signals correctly

TN0172

Product: RPvdsEx
Version: <= 58
Date Added: 2005-03-10

Issue

The MCBiquad does not work with an nBIQ value greater than one. The signal output is zero.

Workaround

Set nBIQ to 1. If a higher Biquad number is required, gang multiple MCBiquads together.

Solution

Upgrade to TDT Drivers v59 or greater.

Coefficients load to FIR or FIR2 filters slowly when using an USB interface

TN0171

Product: RPvdsEx
Version: All
Date Added: 2005-03-10

Issue

Loading a large number of coefficients to an FIR or FIR2 filter can take several seconds when using a USB PC-to-zBus interface. Because coefficient values are loaded to data memory, which does not support block read and writes, values must be loaded from the PC to data memory one value at a time. When using a USB interface this can take between 1 (USB 2.0) and 5 (USB 1.1) milliseconds for each write. Coefficients on the order of 1000 points can take over a second to load.

Workaround

If the upload is too slow, consider using a Gigabit interface, which can improve the transfer rate by 40 times.

A circuit does not run or crashes a device

TN0157

Product: RPvdsEx
Version: All
Date Added: 2004-11-15

Issue

When a circuit that was compiled after upgrading the TDT Drivers does not run or crashes a device, the problem typically relates to either the components in the circuit or the microcode on the device.

The first value sent to a SerSource appears to be skipped when playing out (AutoTuner example project)

TN0155

Product: RPvdsEx
Version: All
Date Added: 2004-10-12

Issue

The first value sent to a SerSource appears to be skipped when playing out. This is most often seen when individual values are being read from a SourceFile to the SerSource.

Solution

When using the SerSource the first value loaded to the SerSource buffer plays out at index 0. When the enable line (IndxEnab) goes high with the first trigger the index is incremented and the next value is sent to the SerSource signal output line. So, at index 1 the second value is played out.

In the figure below, a simple SourceFile to SerSource circuit is shown along with the actual SerSource values (on left) and the values output from the SerSource after each trigger (on right).

To avoid this problem, add a Latch at the output of the SerSource and trigger it with the same enable line used for the SerSource (as pictured below). This will latch the first value when the trigger line goes high for the first time, and each subsequent value will be latched as the triggers occur.

Important Note to OpenEx Users!

This issue can be seen in the OpenEx AutoTuner example project. Make the modifications described here to ensure that epoch events recorded match the values played out.

Problems Synchronizing Waveforms Across Multiple Devices

TN0145

Product: RPvdsEx
Version: All
Date Added: 2004-09-23

Issue

Problems with synchronizing waveforms (such as a triangle wave) and with generating proper delays on two devices are typically a result of differing sample rates. The device with the higher rate can generate waveforms or delays with more resolution than the device at a lower rate. See Tech Note #0143 for more information.

Each TDT device has a fixed set of sample rate capabilities. The use of high- performance sigma-delta DACs makes supporting completely arbitrary rates unreasonable in some devices. For example, the RV8 does not use sigma-delta DACs so it can offer any rate (derived from 25 MHz) while the RX6 uses sigma-delta DACs and thus supports a limited set of sample rates. The setup dialog in RPvdsEX will always return the true available rate for any device when the 'Check Realizable' button is clicked.

Note

TDT software that offers arbitrary delays always bases the actual delay specified on the lowest sample rate used. If the rates are not related by a simple factor of two, four, etc., the actual delays that can be offered can be unsatisfactory.

Workaround

If possible, use standard sample rates that will be related by a simple factor of two, four, etc. If you are using any of the non-linear generator components, be aware that only frequencies related to the sample rate by an integer multiple can be generated.

The zBus trigger stays high longer than expected

TN0144

Product: RPvdsEx
Version: All
Date Added: 2004-09-29

Issue

When the TrigIn component is configured for a software trigger, the trigger will remain high for one sample. However, if the TrigIn is configured for the zBusA or zBusB trigger the time high will depend upon the sample rate. For example, at 6 kHz the trigger will remain high for one sample, but at 25 kHz the trigger will remain high for 5 samples.

Workaround

If you wish to use the zBusA or zBusB trigger and need a single sample trigger pulse, use an EdgeDetect component to detect the rising edge of the trigger before feeding the trigger line to enable, rest, or other triggering parameters.

Pulse trains, triggers, or delays are not the length specified in RPvdsEx

TN0143

Product: RPvdsEx
Version: All
Date Added: 2004-09-23

Issue

When using RPvdsEx components such as PulseTrain, Schmitt, and TTLDelay, that define a high, low, or delay period based on time, the actual time value will be the closest interval depending on the sample rate. For example, at 100 kHz a PulseTrain set to go high for 2 ms would be high for 1.9968 ms, because the sample period is 10.24 us. Because these slight differences are less noticeable on devices using oversampling, such as those using sigma-delta converters, this issue is most noticeable when synchronizing several devices using different types of converters.

Dynamic control of buffer size

TN0142

Product: RPvdsEx
Version: All
Date Added: 2004-09-23

Issue

The buffer size can be controlled dynamically for the SerSource, SerStore, SnipStore, AvgBuf2, and BlockAcc RPvdsEx components. However, the maximum size of the buffer is allocated when the circuit is run. Increasing the defined buffer size while the circuit is running does not affect the memory allocation.

Workaround

Set the buffer size to the maximum value necessary before the circuit is run, then you will be able to decrease the buffer size dynamically while the circuit is running.

'Too many zHops in the circuit' error displayed when trying to compile a circuit

TN0136

Product: RPvdsEx
Version: All
Date Added: 2004-09-01

Issue

A "Too many zHops in the circuit" error is displayed in the messages window when trying to compile a circuit.

Workaround

An RPvdsEx circuit can have a maximum of 126 zHopOuts. One zHopOut is counted for each single zHopOut and for each channel (+1) of a MCzHopOut. That is, a 16 channel MCzHopOut counts as 17 zHopOuts. So, if you have 100 single zHopOuts, then you can have one MCzHopOut with 25 channels {100 + (25+1)}, or two MCzHopOuts with 12 channels each {100 + (12+1) + (12+1)}.

If your circuit exceeds the maximum number of zHopOuts, modify the circuit to have fewer variables shared across processors. For complicated circuit modifications, contact Technical Support for assistance.

A circuit using WordOut or WordIn no longer works properly with TDT Drivers, version 57 or greater

TN0132

Product: RPvdsEx
Version: > 56
Date Added: 2004-08-04

Issue

In TDT Drivers version 57 and greater, the WordOut and WordIn components are implemented differently. Circuits that uses these components will no longer work correctly, if -1 is used as the bitmask.

Note

Changes to the WordIn/WordOut were implemented to accommodate the expanded capabilities of our latest generation processors. Original devices addressed up to 16 bits of I/O with a bitmask word. Newer devices can address up to 40 bits of I/O. To make it possible to address all 40 bits, the first 8 bits in these devices are addressed as individual bits and the next 32 bits are addressed as words.

Solution

Ensure that the WordOut/WordIn uses a bitmask other than -1, then rebuild the RCO file.

MCAdcIn sample delay on channel 16

TN0115

Product: RPvdsEx
Version: 5.4
Date Added: 2004-02-17

Issue

There is a one sample delay on signals acquired via channel 16 of the MCAdcIn.

SimpCount ignores time slice assignment

TN0097

Product: RPvdsEx
Version: All
Date Added: 2003-09-24

Issue

The SimpCount component will always run on every sample, even if it is put into a specific time slice.

Workaround

If time slices are required for your counter, use the Counter component instead of SimpCount.

Multiprocessor and Multichannel components don't work with my processor

TN0092

Product: RPvdsEx
Version: All
Date Added: 2003-08-07

Issue

The Multiprocessor and Multichannel components found in version 5.0 and greater are only used with high-performance processors (such as the RX5 Pentusa processor) and should not be used with RP2s, RA16BAs. See the Multichannel or Multiprocessor sections of the RPvdsEx Manual for more information on these components or the high-performance processors.

Simplifying circuits with Hops

TN0081

Product: RPvdsEx
Version: All
Date Added: 2003-04-25

Issue

RPvdsEx circuits with lots of connecting links can be difficult to read.

Solution

HopTo and HopFrom are RPvdsEx helper components you can use to simplify your circuit designs. Use these complementary components to design complex RPvdsEx circuits without overlapping or confusing links (connection lines). This way, the final circuit appears neat and organized, and the signal path is easy to follow.

To use Hops, link a signal output to a HopTo component and give it a unique name. Then, add a HopFrom function with the same name and link it to the input of any component you want to route that signal to. You can use multiple HopFroms for a single HopTo. Any HopFrom will see the signal from the HopTo with the same name as its source.

RPvdsEx - Simplifying circuits with Hops Comparison

A circuit with no HopTo/HopFrom components is shown below:

The inclusion of HopTo/HopFrom components simplifies circuit analysis:

Using the GaussNoise 'Amp' parameter input

TN0076

Product: RPvdsEx
Version: All
Date Added: 2003-03-12

Issue

In RPvdsEx, the GaussNoise component generates noise that varies in amplitude. The variation in amplitude is normally distributed. The Amp parameter determines the standard deviation of the underlying Normal distribution. Under normal conditions the mean of the signal would be zero. However, you can use the shift parameter to change the mean of the signal.

As a rule of thumb, 68% of the function output will be within one standard deviation, or ± Amp volts rms. Likewise, 95% and 99.7% of all values generated by GaussNoise will be ± 2 and 3 standard deviations from the mean, respectively.

For example, if Amp is 2.2, then 68% of the time the output will be some value between ± 2.2 Vpeak. It follows that there is a roughly 4% chance that the output will be as high as ± 4.4 Vpeak. Of course, the probability of the output clipping at ±10Vpeak is not zero but will occur less than 0.0003% of the time.

PulseTrain2 component never stops pulsing

TN0059

Product: RPvdsEx
Version: All
Date Added: 2002-12-05

Issue

When the nPulse parameter of a PulseTrain2 component is set to a lower value than it previously had, the component will pulse forever, because its internal counter keeps counting from the original value.

Workaround

Set the Enable line of the PulseTrain2 component to 0 before changing nPulse, so that pulsing will be disabled. Trigger the Reset line of the component to reset the internal counter to zero before re-enabling pulsing.

Solution

Upgrade to the latest version of TDT drivers to use the PulseTrain3 component, which does not have this issue.

Phase value outside of (-180, 180) gets set to zero

TN0051

Product: RPvdsEx
Version: All
Date Added: 2002-10-09

Issue

All of the Waveform Generator components (Tone, RampTooth, and SawTooth) ensure that the bounds on the phase parameter are greater than -180 and less than +180. Any value (including exactly -180 or +180) outside of these bounds will be set to a phase of zero.

Workaround

Always use a phase value in the range (-180, 180). If a phase of exactly 180 is needed, use 179.999 instead. For users that are trying to alternate between opposite phases, this can be done using a ScaleAdd component to flip the sign of the waveform.

Circuit will not work correctly after components are added or subtracted

TN0049

Product: RPvdsEx
Version: All
Date Added: 2002-09-24

Issue

When components are added or subtracted from a circuit, the "CmpNo" parameter on the RamBuf and HrtfCoef often need to be changed, otherwise the circuit will not work correctly. In some cases, it requires that you power cycle the hardware.

Workaround

Every time the circuit is recompiled, check the "CmpNo" parameters to make sure they are set to the right value. For any circuit change, change the "CmpNo" parameters as a last step and recompile the circuit.

DestinFile component always writes a 32-bit raw floating-point file, no matter what file type is specified

TN0047

Product: RPvdsEx
Version: All
Date Added: 2002-09-05

Issue

The DestinFile component directly supports only a 32-bit file format. It always writes out a 32-bit raw floating-point file, no matter what file type is specified. Other formats, such as .wav and .txt files, are not supported at this time.

Workaround

A 16-Bit integer format ('. I16') can also be used if the 'Comp to 16' component is used to convert the data to 16 Bit integer format before transferring it to the destination file.

Errors with Peak, Valley, and Tip in FeatSrch component

TN0044

Product: RPvdsEx
Version: All
Date Added: 2002-08-26

Issue

The Peak, Valley, and Tip conditions in the FeatSrch component are not always correct for low-frequency signals. For example, a 1 Hz tone playing for 10 seconds should count 10 peaks, 10 valleys, and 20 tips but 13 peaks, 12 valleys, and 17 tips were actually recorded. Be careful when using these conditions in the FeatSrch component with low-frequency signals (less than 5 Hz).

Documents take an inordinately long time to load (>10 minutes)

TN0013

Product: RPvdsEx
Version: <= 46
Date Added: 2001-12-19

Issue

Adding printers to your Network may change the page description properties of an RPvdsEx document. Any document generated before the printer was installed will take an inordinately long time to load (>10 minutes).

Workaround

Disconnecting the computer from the Network or uninstalling the printer driver will usually solve the problem. If the circuit is important the user can spend about a half an hour to load the file reduce it and then copy and paste it into a new document.

Global zTrig trigger fails

TN0010

Product: RPvdsEx
Version: <= 46
Date Added: 2002-01-10

Issue

Logical devices may have changed when racks were turned on and off. For example, a single device might have shifted from device 1 to device 2. This will cause sending out a global zTrig to fail because zTrig uses the first rack as the Master from which all the others are set. This is only a problem when using the USB interface.

Solution

Rebooting solves this problem.

Tan, Arccos, Arcsin, and Arctan give incorrect values

TN0005

Product: RPvdsEx
Version: All
Date Added: 2002-08-20

Issue

The Trigonometry components: Tan, Arccos, Arcsin, and Arctan give incorrect values. For example:

  • Tan(pi/4) should be 1, but the component's output is 33851.8
  • Arccos(-1) should be pi (3.14159), but the component's output is 3.09164
  • Arcsin(1) should be pi/2 (1.5708), but the component's output is 1.52085
  • Arctan(1) should be pi/4 (.785398), but the component's output is 0.785812

The Tan component should not be used until it is fixed in a new version. The Arccos, Arcsin, and Arctan components should not be used in applications requiring very precise values, until they are fixed in a new version.

Errors occur with Modulus component

TN0004

Product: RPvdsEx
Version: < 80
Date Added: 2002-08-20

Issue

The Modulus component gives incorrect output for some inputs. The problem occurs when modding a multiple of the Mod parameter, i.e., when doing Kx mod x for some non-zero integer K. The output should be zero for these cases, but sometimes the component outputs x. The error has occurred for the following values of x: 3, 5, 6, 10, 12, 13, 15, 17, 20 (only checked up through 20).

Solution

Upgrade to latest version of TDT Drivers.