Online Technical Support — Frequently Asked Questions

            

SyntheSys Data Analyzers

BERTScope, BERTScope S 12500A/7500A
BERTScope™ 12.5/7.5 Gbit/sec Signal Integrity Analyzer Product Page

BA1500
BitAlyzer® 1.5 Gbit/sec Multi-Function BERT Analyzer & Generator Product Page

BA14400B
BitAlyzer®16 Gbit/sec Parallel BERT Analyzer & Generator with Flexible I/O Product Page

BA25B
BitAlyzer® 25 Mbit/sec Bit Error Analyzer. This product is no longer in production. If you own this product and have a question, contact Technical Support.

BA1000
BitAlyzer®1 Gbit/sec Serial Error Analyzer. This product is no longer in production. If you own this product and have a question, contact Technical Support.

BA14400
This product has been superseded by the BA14400B. If you own this product and your question is not answered in the BA14400B FAQ, contact Technical Support.

SyntheSys Video Analyzers

HD292
HD-SDI Video Test System Product Page

MVA3000
Multi-Format Video Test System Product Page

DVA184C
This product is no longer in production. If you own this product and have a question, contact Technical Support.

Frequently Asked Questions — Data Products

How do I interface a TTL signal to the BitAlyzer® ECL serial interface?

When I disconnect the data cable, a few errors are shown and then there are no more errors. What happened?

The BitAlyzer does not consistently recognize my external clock. What's the problem?

What are "events" and how are they used?

What are the mating connectors and cabling for the parallel connectors?

Can I use a mouse with the touchscreen?

Do I need to use the keyboard with my BitAlyzer® or BERTScope™?

What is the procedure for repairing SyntheSys products?

What is the format of the data in the error data file?

My unit runs error free at one frequency but when I switch to another frequency my unit can no longer detect the pattern (gets out of sync).

What is ECL?

Must I follow the internal computer's shutdown process before turning power off to the unit?

How can I get new software?

How do I calibrate my BERTScope™/BitAlyzer®?

What torque is recommend for connecting SMA-type RF Connectors?

I am having difficulties sending multiple write commands through remote control. Commands are being performed slowly or not at all.

What is the maximum clock input amplitude the BA3600 can handle?

What is LVDS?

How do I interface a TTL signal to the BitAlyzer® ECL serial interface?

Because both clock and data inputs/outputs are ECL, you will need some type of ECL-TTL conversion circuitry in order to interface to the unit. Parts such as MC10H124 and MC10H125 can help you do this, but make sure you check the specification of these parts for any compatibility issues with your application (such as speed limitation and power requirements).

When I disconnect the data cable, a few errors are shown and then there are no more errors. What happened?

Because the Resync Threshold has been exceeded, the BitAlyzer^® will attempt to resynchronize to the current pattern of all zeros. Since a PRN pattern never has a long string of all zeros, this presents the detector with a case that does not allow it to detect any errors. There are several strategies that will prevent this case from being a problem:

• Resynchronization can be turned off. Errors will be reported (approximately 5^[3 –1] BER).
• Invert the data out of the generator and invert the data into the detector. Then when a cable is disconnected, the detector will see all "ones" and will not synchronize. Errors will continue to be reported.

The BitAlyzer^® does not consistently recognize my external clock. What's the problem?

The BitAlyzer^® expects an ECL clock input. Ensure that the average level of the clock is –1.25 Volts, and that the setup and hold times are consistent with the specification for the unit.

What are "events" and how are they used?

Events are conditions that the BERTScope™ and BitAlyzer^® recognize and keep track of while processing a data stream. These conditions include external inputs such as Blank and Marker A or B, and process events such as an error in the data stream, hardware or software requesting a resynchronization, resynchronization success, or begin pattern transmission after resynchronization. These conditions are used to aid in the analysis of the events that have transpired while monitoring the data stream.

What are the mating connectors and cabling for the parallel connectors?

The parallel connectors utilize AMP shrouded headers and mate with AMP1-746288-0 IDC 50- Conductor connectors. 3M part number 1700/50 or 1785/50 ribbon cable can be used with these connectors.

Can I use a mouse with the touchscreen?

A mouse can be used with a touchscreen or instead of a touchscreen. Simply add one of the following switches when starting the BitAlyzer^® or BERTScope™ program:

• "-m" when using the mouse driver software that came with our mouse
• That driver must be installed before you run the BitAlyzer^® or BERTScope™ program
• "-m1" when using a serial mouse connected to COM1
• "-m2" when using a serial mouse connected to COM2

Do I need to use the keyboard with my BERTScope™ or BitAlyzer®?

The keyboard is not required for normal operation of the BERTScope™ or BitAlyzer^® . It is convenient for entering filenames when creating new files and for quickly entering text or numeric values into data fields.

What is the procedure for repairing SyntheSys products?

Call SyntheSys Research, Inc. at (650) 364-1853 and ask for Technical Support, or send an email to tech_support@synthesysresearch.com. We will ask you for the serial number of the unit, a person to contact, and the nature of the problem. We will then issue an RMA number and give you a shipping address. Then send it in!

If the unit is out of warranty, there is a $150.00 evaluation fee that is then applied to the repair, should you decide to go ahead with the repair.

What is the format of the data in the error data file?

The BitAlyzer^® and BERTScope™ use a stream of 6-byte events as input data to perform all its error analysis functions. These events encode the position of errors as well as user markers and other supervisory activities. These streams of events can be recorded to the internal hard disk of the BERTScope™/BitAlyzer^® for later post-processing. When recorded to disk, these events are stored in an MS-DOS compatible binary format. Other user written programs to perform custom analysis can conveniently open these files.

The BitAlyzer^® /BERTScope™ 6-byte event is comprised of the following sub-elements:

16-bits XOR (bit position: 0...15)

Exclusive-OR of user data word and expected data word. A binary "1" in any bit position would indicate a mismatch (error) between the user data and the expected data.

24-bits POSITION (bit position: 16...39)

These 24 bits hold a count (in words) of user clocks. For example, an error in the 100th serial bit of a serial stream would have a POSITION count of 6, indicating an error presence in the 7th word. To find which exact bit of the word was in error, one would look at which bit in the XOR word was a logical "1" (mismatch). In this example, it would be the 4th bit. It is guaranteed that at least one event will occur per the 16,777,216 counts of the 24-bit counter to allow a software implementation of a larger counter.

8-bits EVENT (bit position: 40...47)

Each of the 8 bits in this byte is a modifier to the event type. These modifiers are orthogonal, in that one event could have several modifiers. For example, an event could have errors AND be a user marker AND be a RESYNC location. These modifiers are:

• b0 (bit position: 40) Marker 1 (Front Panel BNX)
• b1 (bit position: 41) Marker 2 (Rear Panel)
• b2 (bit position: 42) Data Cycle Marker (Internal)
• b3 (bit position: 43) UNUSED
• b4 (bit position: 44) Start Blank Period Event
• b5 (bit position: 45) Start Resynchronization Event
• b6 (bit position: 46) Begin Error Squelch Event
• b7 (bit position: 47) UNUSED

My unit runs error-free at one frequency but when I switch to another frequency, my unit can no longer detect the pattern (gets out of sync).

One reason for this is the fact that data-to-clock relationship changes with frequency and they can be shifted out of phase from each other. The solution is to delay the clock or data so that the timing for both data and clock are aligned properly. One trick you can use is to check "Invert Clock" (I/F Settings) on the detector and this may sufficiently realign clock and data.

What is ECL?

Emitter-Coupled Logic: The typical logic level is –0.95 V high, and –1.7 V low, with about a 750 mV swing. It is designed to drive a 50-ohm impedance and a –2 V termination. Advantages of ECL include low propagation delays with moderate edge rates, negligible noise and ground bounce, constant power consumption over frequency, and the ability to drive low impedance transmission lines.

Must I follow the internal computer's shutdown process before turning power off to the unit?

Yes, the unit MUST be allowed to complete the full shutdown process prior to turning power off to the unit. Failure to do so may lead to corruption of files on the unit's internal hard disk.

How can I get new software?

Simply contact SyntheSys Research, Inc., at +1 (650) 364-1853 and ask for Technical Support, or send an email to tech_support@synthesysresearch.com to request your software update.

During the warranty period, SyntheSys Research will update your software for free. After the warranty ends, there is a nominal charge for a software upgrade.

How do I calibrate my BitAlyzer® /BERTScope™?

Yearly factory calibration is recommended for your BitAlyzer^® or BERTScope™. This calibration cannot be performed in the field. Contact Technical Support by calling (650) 364-1853, or sending email to tech_support@synthesysresearch.com, regarding returning your BitAlyzer^® or BERTScope™ to the factory for calibration.

What torque is recommend for connecting SMA-type RF Connectors?

A 56 N-cm torque wrench should be used to connect male SMA connectors to either 3.5 mm or 2.92 mm connectors.

I am having difficulties sending multiple write commands through remote control. Commands are being performed slowly or not at all.

After every write command from the host is processed, the unit returns a status or text value and waits for the host to read it, or waits for timeout, before the bus can be cleared and the next command from the host can be processed. If a read command is not issued, the host computer will have to wait until the unit times out before it performs the next command, and this may cause a backup on the communication bus, slowing the communications process.

What is the maximum clock input amplitude the BA3600 can handle?

Maximum allowable input is 2 V peak-to-peak.

What is LVDS?

Low Voltage Differential Signaling: LVDS features a low voltage swing, 400 mV single-ended maximum, is connected point-to-point, and achieves low power dissipation. The driver output signal swing is 250 mV to 400 mV centered at 1.2 V.

Frequently Asked Questions — Video Products

What is the calibration interval for the Video BitAlyzer® and how do I calibrate it?

How can I use the GPI input?

What is the difference between 1080-P/24 and 1080-SF/24?

Why does some equipment show F-bit errors on a BitAlyzer® HDVA?

What is the procedure for repairing SyntheSys products?

What are the maximum and minimum values one can set for Data Low and Data High values in Error Selection's Format Event?

Must I follow the NT shutdown process before turning power off to the unit?

When viewing the HD Jitter Spectrum, why is there a discrepancy in jitter amplitude measurement between the 5 kHz/division band and the 50 kHz/ division band?

Why, on rare occasions, is the DVA184C's 'Sync Detect' status valid when no valid video signal is sent to the DVA184C?

What is the calibration interval for the Video BitAlyzer^® and how do I calibrate it?

SyntheSys Research, Inc., recommends that BitAlyzer^® units be calibrated annually. This calibration cannot be performed in the field. Call (650) 364-1853 and ask for Technical Support, or send an email to tech_support@synthesysresearch.com regarding returning your BitAlyzer^® to the factory for calibration.

How can I use the GPI input?

The GPI input can be used to trigger a frame grab by inserting an external TTL signal.

The frame will be grabbed on the low to high signal transition. This can be useful to isolate and analyze a specific erred frame that is causing problems.

NOTE: Grab must be enabled in the Event Log for this feature to work.

What is the difference between 1080P/24 and 1080SF/24?

The 1080-P/24 source format defines a 1920 x 1080 active picture area image that is scanned progressively 24 times per second (or 23.976 Hz if in an NTSC plant). This data is inserted into the SMPTE- 292M transport exactly as it is scanned—as a single atomic unit per frame. In this source format, the F-bit has no meaning, since there are no separated fields.

The 1080-SF/24 source format also defines a 1920 x 1080 active picture area image that is scanned progressively 24 times per second. However, this data is subsequently split (or 'segmented') into odd lines and even lines. The odd lines are transported through the SMPTE 292M transport first, in what appears to be a field containing odd lines (F1). Immediately afterwards, the even lines are transported in a field containing even lines (F2). The F-bit is set as if the two segments were separate fields.

These differences highlight the usefulness of being able to separate the scanning format from the transport format. In both cases, the Images were scanned progressively, but in the latter (1080SF/24) source format, the image is transported in the same fashion that interlaced fields are transported.

One advantage of this approach is that the 1080SF/24 signal may be plugged into an interlace-type monitor for viewing. The monitor would scan the odd lines of the progressive image, then the even lines, and would apparently refresh the screen at 48 Hz. Actually, like interlaced systems, only the even or odd lines are being refreshed each 1/48th of a second, but still, it would possess far less flicker than a true progressively scanned image refreshing at a 24 Hz frame rate.

One disadvantage of this approach is that someone downstream, or in the future, may feel it is acceptable to perform field-based processing instead of frame-based processing. This could split the odd and even lines of a progressive scan image, which would not be the correct thing to do.

The 1080P/24 source format existed prior to the 1080SF/24 source format. Indeed, it existed on paper before the need was practically identified. In the Spring of 1999, it became clear to proponents of 1080SF/24 that it would be much easier to provide 24 Hz progressive equipment and infrastructure if existing interlaced systems could be modified and upgraded for speed, compared to developing new 24 Hz equipment from scratch.

Why does some equipment show F-bit errors on a BitAlyzer^® HDVA?

Earlier equipment that was compliant with a 1996 version of the SMPTE 274M spec will show an F-bit error, since later versions of this spec moved the location of the F-bit.

What is the procedure for repairing SyntheSys products?

Call SyntheSys Research, Inc. at (650) 364-1853 and ask for Technical Support, or send an email to tech_support@synthesysresearch.com. We will ask you for the serial number of the unit, a person to contact, and the nature of the problem. We will then issue an RMA number and give you a shipping address. Then send it in!

If the unit is out of warranty, there is a $150.00 evaluation fee that is then applied to the repair, should you decide to go ahead with the repair.

What are the maximum and minimum values one can set for Data Low and Data High values in Error Selection's Format Event?

In the Error Selection Format Event dialog for both Luma and Chroma data, the low minimum is 004h, and maximum is whatever data high is set to. Data high minimum is whatever data low is set to, and data maximum is 3FBh 004h-3FBh.

Must I follow the internal computer's shutdown process before turning power off to the unit?

Yes, the unit MUST be allowed to complete the full shutdown process prior to turning power off to the unit. Failure to do so may lead to corruption of files on the unit's internal hard disk.

When viewing the HD Jitter Spectrum, why is there a discrepancy in jitter amplitude measurement between the 5 kHz/division band and the 50 kHz/division band?

The HDVA integrates the total jitter energy within a division. In the 5 kHz/div band, the jitter amplitude for one division is equal to the integration of the total energy within a 100 Hz range of the frequency. For the 50 kHz/div band, the amplitude is equal to the integration of the total energy within a 1 kHz range of the frequency. When wideband jitter is measured, this difference in integration band can result in different apparent measurements.

Why, on rare occasions, is the DVA184C's "Sync Detect" status valid when no valid video signal is sent to the DVA184C?

The DVA184C has a high input sensitivity and it is possible for the DVA to sync to a non-standard video signal. To use the DVA to qualify a valid SDI video signal, it is recommended that at least the "TRS Detect" and "Sync Detect" (both) are monitored.