Envision Peripherals NV3128 User manual

NV3128

RS-422A Machine-Control Data

Routing Switch

Manual Part Number: MN3128-00B

Instruction Manual

NVISION

Printing History

Model NV3128 Manual, Edition 2

Printed in the U.S.A.

Copyright

NVision, Incorporated

January, 2000

July, 1993

No part of this manual may be reproduced in any form by photostat, microfilm,

xerography, or any other means, or incorporated into any information retrieval

system, electronic or mechanical, without the written permission of NVISION, Inc.

Notice

The information contained in this Operations Manual is subject to change without

notice or obligation.

Warranty Statement

NVISION, Inc. warrants that the equipment it manufactures shall be free from defects in materials and

workmanship for a period of two (2) years, optionally extendable to five (5) years, from the date of shipment

from the factory. If warranted equipment fails due to such defects, NVISION, Inc. shall, at its option, repair

or provide replacement for the defective part or product.

Equipment that fails after the warranty period, or that which has been operated outside its ratings or

subjected to abuse, shall be repaired for time and material charges at the Buyers expense. All out-of-

warranty repairs are warranted for a period of ninety (90) days from the date of shipment from the factory.

NVISION, Inc. makes no warranties, expressed or implied, of merchantability, fitness for a particular

purpose or otherwise. With respect to the products sold by it, NVISIONs liability for any cause, including

breach of contract, breach of warranty or negligence, is limited to repair or replacement by NVISION, at

its sole discretion. This remedy is exclusive.

In no event shall NVISION be liable for any incidental or consequential damages, including loss of profit.

Year 2000 Warranty Statement

NVISION, Inc. warrants that all of its hardware, firmware, and software products are not date-code sensitive

and that their functionality will not be affected or altered in any way by a 21st century date code.

NVISION cannot warrant that the performance of NVISION products will not be impaired by interaction with

third party equipment and software systems that may not be year 2000 compliant.

NVISION internal operations, manufacturing services, accounting systems and engineering programs

have been determined to be year 2000 compliant and it is not anticipated that a 21st century date will affect

the functionality of our business.

We are investigating our supply channels for components and services to ensure that they will not be

affected by a 21st century date code, but we cannot warrant that our products or services will not be

affected by external services beyond NVISION control.

Disclaimer

NVISION disclaims all responsibility for product or service impairments that may arise due to interaction with

third party products, equipment, or services that are not year 2000 compliant.

Technical Support

If you need support of any kind related to your equipment, contact the local representative who sold you

the product, or you may contact NVISION, Inc. directly by any of the following methods.

Telephone Main Telephone: (530)-265-1000

Technical Support: (530) 265-1059

Sales: 800-719-1900 or (530)-265-1000

Facsimile Main FAX Number: (530)-265-1010

Sales: (530)-265-1021

Email Technical Support: [email protected]

Sales: [email protected]

Postal Addresses Shipping Address: Mailing Address:

NVISION, Inc. NVISION, Inc.

125 Crown Point Court PO Box 1658

Grass Valley, CA 95945 Nevada City, CA 95959

FCC (USA) Compliance Statement

This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant

to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful

interference when the equipment is operated in a commercial environment.

This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in

accordance with the instruction manual, may cause harmful interference in which case the user will be

required to correct the interference at their own expense.

European Community (CE) Declaration of Conformance

Some or all of the equipment described in this manual has been designed to conform with the required

safety and emissions standards of the European Community. Products tested and verified to meet these

standards are marked as required by law with the CE mark.

When shipped into member countries of the European Community, this equipment is accompanied by

authentic copies of original Declarations of Conformance on file in NVISION corporate headquarters in

Nevada City, California, USA.

Important Safeguards and Notices

The information on the following pages provides important safety guidelines for both operator and service

personnel. Specific warnings and cautions appear throughout the manual where they apply. Please read

and follow this important safety information, especially those instructions related to the risk of electric shock

or injury to persons.

WARNING: Any instructions in this manual that require opening the equipment cover or

enclosure are for use by qualified service personnel only. To reduce the risk of electric shock,

do not perform any servicing other than that contained in the operating instructions unless you

are qualified to do so.

Symbols and Their Meanings

The lightning flash with arrowhead symbol within an equilateral triangle alerts the user to

the presence of dangerous voltages within the products enclosure that may be of sufficient

magnitude to constitute a risk of electric shock to persons.

The exclamation point within an equilateral triangle alerts the user to the presence of

important operating and maintenance/service instructions. These instructions may include

warnings or cautions advising about the potential for damage to equipment or danger to

personnel.

The Ground symbol represents a protective grounding terminal. Such a terminal must be

connected to earth ground prior to making any other connections to the equipment.

The fuse symbol indicates that the fuse referenced in the text must be replaced with one

having the ratings indicated.

The presence of the UL symbol in or on NVISION equipment means that it has been

designed, tested and certified as complying with applicable Underwriters Laboratory

(USA) regulations and recommendations.

The presence of the CE symbol in or on NVISION equipment means that it has been

designed, tested and certified as essentially complying with all applicable European Union

(CE) regulations and recommendations.

U

R

Warnings

A warning indicates a possible hazard to personnel which may cause injury or death. Observe the following

general warnings when using or working on this equipment.

- Heed all warnings on the unit and in the operating instructions.

- Do not use this equipment in or near water.

- This equipment is grounded through the grounding conductor of the power cord. To avoid electrical shock,

plug the power cord into a properly wired receptacle before connecting the equipment inputs or outputs.

- Route power cords and other cables so they are not likely to be damaged.

- Disconnect power before cleaning the equipment. Do not use liquid or aerosol cleaners; use only a damp

cloth.

- Dangerous voltages may exist at several points in this equipment. To avoid personal injury, do not touch

exposed connections and components while power is on.

- Do not wear rings or wristwatches when troubleshooting high current circuits such as the power supplies.

- During installation, grasp the chassis of the equipment firmly and lift with your legs; do not bend over at

the waist to lift heavy items. Moreover, do not rely on door handles or front panels to lift the equipment

as they are not intended for this purpose.

- To avoid fire hazard, use only the specified fuse(s) with the correct type number, voltage and current

ratings as referenced in the appropriate locations in the service instructions or on the equipment. Always

refer fuse replacements to qualified service personnel.

- To avoid explosion, do not operate this equipment in an explosive atmosphere.

- Have qualified service personnel perform safety checks after any completed service.

- If equipped with redundant power supplies, the equipment has two power cords. To reduce the risk of

electric shock, disconnect both power supply cords before servicing the unit.

Cautions

A caution indicates a possible hazard to equipment that could result in equipment damage. Observe

the following general cautions when operating or working on this equipment.

- When installing this equipment, do not attach the power cord to building surfaces.

- To prevent damage to equipment when replacing fuses, locate and correct the problem that caused

the fuse to blow before re-applying power.

- Verify that all power supply lights are off before removing the power supply or servicing the equip-

ment.

- Use only the specified replacement parts.

- Follow static precautions at all times when handling this equipment.

- This product should only be powered as described in the manual. To prevent equipment damage,

select the proper line voltage at the AC input connector (if applicable) as described in the installation

documentation.

- To prevent damage to the equipment, read the instructions in the equipment manual for proper input

voltage range selection.

- To maximize protection against unwanted power loss, ensure that the power cords for redundant

power supplies are plugged into separate branch circuits.

North American Power Supply Cords

The power cords supplied with this equipment have a molded grounding plug (NEMA 5-15P) at one

end and molded grounding receptacle (IEC 320-C13) at the other end. Conductors are CEE color-

coded: Light blue (neutral), Brown (line) and Green or Green/Yellow (ground).

Operation of this equipment at voltages exceeding 130 VAC will require power supply cords which

comply with NEMA configurations.

Line

Neutral

Ground (Earth)

Green or Green

with Yellow Stripe

Blue

Brown

International Power Supply Cords

The power cords supplied with this equipment have a molded grounding receptacle (IEC 320-C13) at

one end and stripped conductors (50/5 mm) at the other end. Conductors are CEE color-coded: Light

blue (neutral), Brown (line) and Green/Yellow (ground). Other IEC 320-C13 type power supply cords

can be used if they comply with the safety regulations of the country in which they are installed.

Line

Neutral

Ground (Earth)

Green with

Yellow Stripe

Blue

Brown

TABLE OF CONTENTS

1. GENERAL INFORMATION ........................................................................................ 1-1

1.1 General .................................................................................................... 1-3

1.2 Architecture .............................................................................................. 1-4

1.3 I/O .......................................................................................................... 1-12

1.4 Physical .................................................................................................. 1-12

1.5 Ancillary Equipment ................................................................................ 1-13

1.6 Specifications ......................................................................................... 1-14

2. INSTALLATION .......................................................................................................... 2-1

2.1 HARDWARE INSTALLATION .................................................................... 2-3

2.2 CONFIGURATION .................................................................................... 2-6

2.3 CABLING ................................................................................................ 2-14

2.4 ADDING A REDUNDANT CONTROLLER ............................................... 2-18

2.5 IMPLEMENTING HOT CHANGEOVER ................................................... 2-18

2.6 PC DIAGNOSTIC INTERFACE ................................................................ 2-19

3. OPERATION ............................................................................................................... 3-1

3.1 CONNECTION NOTES ............................................................................. 3-3

3.2 COMPUTER UTILITIES ............................................................................. 3-5

4. THEORY OF OPERATION ........................................................................................ 4-1

4.1 System ...................................................................................................... 4-3

4.2 Circuit Operation ...................................................................................... 4-5

5. MAINTENANCE AND TROUBLESHOOTING .......................................................... 5-1

5.1 Customer Support .................................................................................... 5-3

5.2 Scheduled Maintenance ........................................................................... 5-3

5.3 Reliability .................................................................................................. 5-3

5.4 Troubleshooting ........................................................................................ 5-4

GLOSSARY ................................................................................................................... G-1

INDEX...................................................................................................................... Index-1

NV3128 RS-422A Machine-Control Data Switch 1-1

CHAPTER 1: GENERAL INFORMATION

NV3128 RS-422A Machine-Control Data Switch 1-2

NV3128 RS-422A Machine-Control Data Switch 1-3

CHAPTER 1 - GENERAL INFORMATION

1.1 GENERAL

The NV3128 is a serial digital switch for routing RS-422A machine-control

data in a video or audio broadcast or production facility. Table 1.1 at the end

of this section lists its performance specifications.

Requiring only eight units of a 19" EIA rack for a bi-directional, 128-machine

array, the NV3128 achieves a 10:1 space reduction over traditional analog or

relay routers. Its non-blocking matrix architecture and unique dynamic port-

configuration capability combine to vastly simplify the cumbersome routing

of duplex machine-control signals. The system is capable of multidrop

RS422-A chains without bus contention.

At the heart of the NV3128 is the Control Card/Command Interpreter, which

parses the command strings from any of a large number of commonly available

router-control systems into physical from and to crosspoint addresses. Further,

the Interpreter gleans from those commands the information it needs to

configure the I/O ports. Transparently, the Interpreter allows the NV3128 to

be steered by the same routing-control system that drives a plants program

and other auxiliary data switching.

The NV3128 can be synchronized to a video black burst signal or it can free

run. Takes occur during the vertical retrace interval of the video reference, or

during a calculated recreation of that interval if video is not present.

Router control systems typically communicate over serial RS-422A lines,

and this is what the new Universal Control Card uses. The obsolete Command

Interpreter card used in older models additionally supported RS-232 and a

parallel RS-422A implementation for such hardware interfaces as the Horizon

control protocol.

PC-compatible software furnished with the unit provides extensive

configuration, query and diagnostic utilities. Finally, should it prove undesirable

to merge the machine data route-control system into the program control, the

NV3128 comes with a simple, easy-to-use PC-based control system.

To enhance system reliability, the NV3128 frame houses an optional, fully

redundant 80-watt power supply. The outputs of the first and second supplies

share the load equally, but in the event of a failure, either can handily power

the system solo. Sensing circuitry activates an alarm relay on each power

supply, with contacts brought out for operating an external alarm. In the event

of a power failure, a one farad capacitor charge maintains power on a backup

SRAM bank, keeping the mapping of the switch intact for no less than 3 days.

NV3128 RS-422A Machine-Control Data Switch 1-4

For very high reliability applications, a redundant controller can also be added

to the frame, with circuitry provided for automatic changeover.

With its duplex complexity, RS-422A has long been a troublesome method of

plant signal routing. The NV3128 untangles the problems unique to this data

type to offer an innovative, low-cost solution that merges easily into a facilitys

over-all routing plan.

A scaled-down version of the switch, with 64 of the 128 ports enabled, is

available as model NV3128-64.

1.2 ARCHITECTURE

BACKGROUND:

The duplex nature of RS-422A communication creates its own level of

complexity. The Electronic Industry Associates RS-422A, is a balanced,

serial, 4-wire transmission technique with a line driver and receiver at either

end of the link. In the typical video or audio production-machine hookup, one

machine is master, and one or more machines are slaved. The master is

referred to as a controlling device, the slave as a controlled device. The

controlling device issues commands to the controlled device via a D connector

over pin pair 3/8. The controlled device receives the commands over the same

pin pair, 3/8, and transmits status, acknowledgement and diagnostic data

back over pin pair 2/7. The controlling device receives this feedback over pin

pair 2/7. Fig. 1.1 illustrates this fundamental connection.

NV3128 RS-422A Machine-Control Data Switch 1-5

NV3128 RS-422A Machine-Control Data Switch 1-6

Because commands are broadcast on one balanced pair and responses

received on another, the systems crosspoint count, wiring density and complexity

are inherently double that of a video or audio router. Fig. 1.2 shows the two-

level connection required to implement a route through a conventional data

switch. To pass through the switch, the connection must be separated into two

components: the command, which travels from source to destination, and the

response, which returns through the switch from destination to source. Cables

are split such that transmitting pins from both machines are hooked to switch

input blocks, and receivers to output blocks. Additionally, the router-control

system must be highly specialized, for it now must address two connections

with every connect command it issues.

NV3128 RS-422A Machine-Control Data Switch 1-7

To further complicate matters, the sense of transmit and receive connections

in many modern machines is switchable. That is, internal circuitry within the

machine reassigns the interface pin assignments to allow it to operate in either

controlled or controlling mode. Fig. 1.3 illustrates the physical pin swapping

within each of two directly connected devices. On most units the changeover

is a physical switch, but on some, such as the Sony D1 VTR, the pin flip is

under software control. In either case, the traditional routing switch cannot

adapt to a reversal of data direction, and thus severely compromises a systems

flexibility. Referring again to Fig. 2, note that the physical connection fixes the

operating mode - controlled or controlling - of the device. If pin pair 3/8 from

a machine is connected to a router input, then that machine is a controlling

device from now until someone gets out a crimping tool and rewires the

connection.

Yet another frustration in implementing a switched machine-control system:

one-to-many connections have historically been problematic. Sending a

command down a daisy chain of slaved devices is not difficult, and many

machines provide a second D connector to accommodate the cable loop

through. But it is difficult for the controlling device to discern which of the

slaved machines is responding, and - worse- there is a strong probability of

bus contention. Again, the user must get out of his chair, find his trusty crimping

tool, and disable the responding transmit connection on all but one of the

controlled machines. While keeping plant technicians gainfully employed, this

activity defeats the purpose of a routing switch.

NV3128 RS-422A Machine-Control Data Switch 1-8

Video equipment offers a sufficient diversity of control options to add another

layer of complexity to routing.

The Sony BVU machines have a single D connector for both controlling and

controlled traffic. The direction of data traffic is controlled by the remote

switch.

The Sony BETA machines hard wire two D connectors together, again for both

controlled and controlling traffic. Although the second connector facilitates

daisy-chained control, it does nothing to diminish the probability of bus

contention this feature invites.

D1 and D2 VTRs use two D connectors, configurable with software as

controlled or controlling. Additionally, these machines can resolve their

involvement in bus contention in a daisy-chained control configuration.

Traditionally, installations have resorted to relay routers or analog audio

routers to switch machine control data, and have just had to tolerate the

limitations and expense caused by the logistical complexity. Analog audio

routers and relay routers share three further disadvantages: They take up a lot

of space, they use a lot of electricity and they cost a lot money.

A SOLUTION:

The NV3128 fully addresses the idiosyncrasies of routing RS-422A machine

control data. Its compact, eight rack-unit frame is small enough to be installed

in the suite. Its 65 watt off-the-line power requirement is less than most light

bulbs. And its cost is a fraction of alternative solutions. Capable of NRZI data

rates up to 5 Mbits/Sec., it offers 128 I/O ports in a non-blocking X-Y matrix.

It is also available in a 64-port configuration that can be field upgraded to 128

ports by simply adding an additional I/O module.

NV3128 RS-422A Machine-Control Data Switch 1-9

DYNAMIC PORTS

The power of the NV3128 as a data router begins with its singular ability to

dynamically configure each of its 128 I/O ports to one of three states:

controlling, controlled or high impedance. Executed automatically with each

take command, this transparent changeover action in the router emulates the

mode-swapping capability of the external machines. It simultaneously simplifies

a system and expands its overall capability.

Fig. 1.4 illustrates this essential circuit function. Each I/O port presents a

physical implementation of the standard RS-422A interface, to which a

machine is connected without regard to data direction. Between the physical

interface and the X-Y crosspoint matrix is a gated pair of RS-422A transceivers.

Upon receipt of a Take command, the routers Control Card/Command

Interpreter parses the incoming connection information and designates the

port to which the source device is connected as controlled and the port to

which the target is connected as controlling. It then sends this state of the

port information to port controllers on the I/O modules. These port

controllers, in turn, send gating signals to the transceiver pairs, turning the

receivers and transmitters on or off appropriate to the direction of data flow.

The valid port states are controlling , controlled, and controlling no response

routed.

+

-

+

-

NV3128 RS-422A Machine-Control Data Switch 1-10

CROSSPOINT ARCHITECTURE

Figure 1.5 is a simplified representation of the interface between the I/O

connectors, the dynamic ports, and the crosspoint matrix. The crosspoint

matrix itself consists of four LSI 64x64 crosspoint chips connected in a

unidirectional 128x128 m by n architecture. In this non-blocking scheme,

any of the 128 inputs can be switched to any of the 128 outputs. Each output

is controlled by a double-buffered register with a load and an active segment.

Upon receipt of an XY take command, the command interpreter fills the load

segment with the address of the input port to which the output will be

connected. The take is consummated when the crosspoint strobe dumps the

contents of the load registers into the active registers. The entire process of

mapping the switch in this fashion occurs within one video vertical retrace

time.

At the crosspoint level, the NV3128 is an X-Y matrix switch. But from the

vantage point of the user, the semantics of routing architecture break down: the

straightforward concepts of input and output, sufficient to describe program

route matrices, no longer have meaning. Despite the complexity, inherent in the

dynamic ports is an expanded capability. Unlike a program router, which has

a fixed I/O dimension, each of the 128 ports can be connected to any other

port. Each of the ports can be either source or destination.

For each requested machine connection, the router uses the input command

information to ensure that the controlling machine automatically sees a controlled

router port, and that the controlled machine looks back into a controlling port.

In practice, this means that the NV3128 can dynamically implement the

connections of Fig. 1 and Fig 3 in successive sessions. In Fig. 1.1, the editor

controls VTR A, which is a controlled device. In a further session, VTR A

dubs down to VTR B, with VTR A now a controlling device, as shown in Fig.

1.3. In a conventional routing switch, this arrangement would require physical

re-connecting of the machines involved. Although there are routing systems

with high-impedance outputs that can be forced into such a mapping, the cost

is a doubling of the number of connections, a 4-times expansion of the number

of crosspoints, and associated increments in operating costs.

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Envision Peripherals NV3128 User manual

Envision Peripherals NV3128 User manual

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