ZyXEL Communications P841C User Manual

P841C

Central-Side VDSL Modem

May 2002

Version 1.00

User’s Guide

P841C Central-Side VDSL Modem

Copyright

Copyright © 2002 by ZyXEL Communications Corporation

The contents of this publication may not be reproduced in any part or as a whole, transcribed, stored in a retrieval
system, translated into any language, or transmitted in any form or by any means, electronic, mechanical,
magnetic, optical, chemical, photocopying, manual, or otherwise, without the prior written permission of ZyXEL
Communications Corporation.

Published by ZyXEL Communications Corporation. All rights reserved.

Disclaimer

ZyXEL does not assume any liability arising out of the application or use of any products, or software described
herein. Neither does it convey any license under its patent rights nor the patents rights of others. ZyXEL further
reserves the right to make changes in any products described herein without notice. This publication is subject to
change without notice.

Trademarks

Trademarks mentioned in this publication are used for identification purposes only and may be properties of their
respective owners.

ii Copyright

P841C Central-Side VDSL Modem

ZyXEL Limited Warranty

ZyXEL warrants to the original end user (purchaser) that this product is free from any defects in materials or
workmanship for a period of up to two (2) years from the date of purchase. During the warranty period and upon
proof of purchase, should the product have indications of failure due to faulty workmanship and/or materials,
ZyXEL will, at its discretion, repair or replace the defective products or components without charge for either
parts or labor and to whatever extent it shall deem necessary to restore the product or components to proper
operating condition. Any replacement will consist of a new or re-manufactured functionally equivalent product of
equal value, and will be solely at the discretion of ZyXEL. This warranty shall not apply if the product is
modified, misused, tampered with, damaged by an act of God, or subjected to abnormal working conditions.

Note

Repair or replacement, as provided under this warranty, is the exclusive remedy of the purchaser. This warranty is
in lieu of all other warranties, express or implied, including any implied warranty of merchantability or fitness for
a particular use or purpose. ZyXEL shall in no event be held liable for indirect or consequential damages of any
kind of character to the purchaser.

To obtain the services of this warranty, contact ZyXEL's Service Center for your Return Material Authorization
number (RMA). Products must be returned Postage Prepaid. It is recommended that the unit be insured when
shipped. Any returned products without proof of purchase or those with an out-dated warranty will be repaired or
replaced (at the discretion of ZyXEL) and the customer will be billed for parts and labor. All repaired or replaced
products will be shipped by ZyXEL to the corresponding return address, Postage Paid. This warranty gives you
specific legal rights, and you may also have other rights that vary from country to country.

ZyXEL Limited Warranty iii

P841C Central-Side VDSL Modem

Interference Statements and Warnings

FCC Interference Statement

This device complies with Part 15 of the FCC rules. Operation is subject to the following two conditions:

(1) This device may not cause harmful interference.

(2) This device must accept any interference received, including interference that may cause undesired operations.

FCC Warning

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part
15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference 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 to radio
communications. Operation of this equipment in a residential area is likely to cause harmful interference in which
case the user will be required to correct the interference at his own expense.

CE Mark Warning:

This is a Class B product. In a domestic environment this product may cause radio interference in which case the
user may be required to take adequate measures.

Taiwanese BCIQ A Warning:

VCCI Class B Warning

Certifications

Refer to the product page at www.zyxel.com.

iv Interference Statements and Warnings

P841C Central-Side VDSL Modem

Customer Support

If you have questions about your ZyXEL product or desire assistance, contact ZyXEL Communications
Corporation offices worldwide, in one of the following ways:

Contacting Customer Support

When you contact your customer support representative, have the following information ready:

♦ Product model and serial number.
♦ Firmware version information.
♦ Warranty information.
♦ Date you received your product.
♦ Brief description of the problem and the steps you took to solve it.

METHOD E-MAIL: SUPPORT TELEPHONE WEB SITE

LOCATION SALES FAX FTP SITE

WORLDWIDE

AMERICA

MALAYSIA

[e-mail] [phone] www.zyxel.com

www.europe.zyxel.com

[e-mail]

[e-mail] [phone]

[e-mail]

[e-mail] [phone] www.zyxel.dk SCANDINAVIA

[e-mail] [phone] ftp.zyxel.dk

[e-mail] [phone] www.zyxel.de GERMANY

[e-mail] [phone]

[e-mail]

[e-mail]

[phone] ftp.europe.zyxel.com

www.zyxel.com NORTH

800-255-4101

[phone] ftp.zyxel.com

[phone]

[phone]

www.zyxel.com.my

REGULAR MAIL

ZyXEL Communications
Corp., 6 Innovation Road
II, Science-Based
Industrial Park, HsinChu,
Taiwan 300, R.O.C.

ZyXEL Communications
Inc., 1650 Miraloma
Avenue, Placentia, CA
92870, U.S.A.

ZyXEL Communications
A/S, Columbusvej 5, 2860
Soeborg, Denmark.

ZyXEL Deutschland
GmbH. Adenauerstr.
20/A4 D-52146
Wuerselen, Germany.

Lot B2-06, PJ Industrial
Park, Section 13, Jalan
Kemajuan, 46200
Petaling Jaya Selangor
Darul Ehasn, Malaysia

Customer Support v

P841C Central-Side VDSL Modem

Table of Contents

Copyright ...................................................................................................................................................................ii

ZyXEL Limited Warranty...........................................................................................................................................iii

Interference Statements and Warnings ....................................................................................................................iv

Customer Support .................................................................................................................................................... v

Preface .....................................................................................................................................................................ix

Chapter 1 Getting to Know the P841C................................................................................................................................. 1-1

1.1 Features..................................................................................................................................................... 1-1

1.2 Application Example .................................................................................................................................. 1-1

Chapter 2 Hardware Connections........................................................................................................................................ 2-1

2.1 Front Panel ................................................................................................................................................ 2-1

2.2 Back Panel................................................................................................................................................. 2-1

Chapter 3 Configuring the P841C ........................................................................................................................................ 3-1

3.1 Additional Installation Requirements ......................................................................................................... 3-1

3.2 Login Screen..............................................................................................................................................3-1

3.3 Commands ................................................................................................................................................3-2

3.4 System Related Commands......................................................................................................................3-2

Chapter 4 VDSL- Related Commands ................................................................................................................................. 4-1

4.1 Introduction ................................................................................................................................................ 4-1

Chapter 5 Ethernet-related Commands............................................................................................................................... 5-1

5.1 Introduction ................................................................................................................................................ 5-1

Chapter 6 Troubleshooting .................................................................................................................................................. 6-1

6.1 VDSL LED..................................................................................................................................................6-1

6.2 Data Transmission.....................................................................................................................................6-1

6.3 Intermittent VDSL LED ..............................................................................................................................6-2

6.4 Data Rate................................................................................................................................................... 6-2

6.5 Password ................................................................................................................................................... 6-2

6.6 Connecting to an Ethernet Switch ............................................................................................................. 6-2

Power Adapter Specifications...................................................................................................................................A

Index .........................................................................................................................................................................C

vi Table of Contents

P841C Central-Side VDSL Modem

List of Figures

Figure 1-1 Campus Application ..................................................................................................................................................1-2

Figure 2-1 P841C Front Panel.....................................................................................................................................................2-1

Figure 2-2 P841C Back Panel .....................................................................................................................................................2-2

Figure 3-1 Login Screen..............................................................................................................................................................3-1

Figure 3-2 Login Screen..............................................................................................................................................................3-1

Figure 3-3 Wrong Password........................................................................................................................................................3-2

Figure 3-4 Change Password Command .....................................................................................................................................3-2

Figure 3-5 Exit Command...........................................................................................................................................................3-3

Figure 3-6 P841C Help Commands ............................................................................................................................................3-3

Figure 3-7 Sys Status Command.................................................................................................................................................3-5

Figure 3-8 Upgrading Firmware First Warning...........................................................................................................................3-5

Figure 3-9 Upgrade Firmware Last Warning...............................................................................................................................3-6

Figure 3-10 Example Xmodem Upload ......................................................................................................................................3-6

Figure 4-1 VDSL Mode...............................................................................................................................................................4-1

Figure 4-2 VDSL Upstream Rate ................................................................................................................................................ 4-2

Figure 4-3 VDSL Downstream Rate ...........................................................................................................................................4-3

Figure 4-4 VDSL Auto Flag........................................................................................................................................................4-3

Figure 4-5 VDSL Status Example...............................................................................................................................................4-4

Figure 4-6 VDSL Initialization Messages...................................................................................................................................4-6

Figure 4-7 VDSL Monitor...........................................................................................................................................................4-6

Figure 4-8 VDSL Show Command .............................................................................................................................................4-7

Figure 5-1 Ethernet Status...........................................................................................................................................................5-2

Figure 5-2 Ethernet Speed...........................................................................................................................................................5-3

Figure 5-3 Ethernet Flow Control ...............................................................................................................................................5-3

Figure 5-4 Ethernet Monitor Status.............................................................................................................................................5-4

Figure 5-5 Enet Monitor Statistics ..............................................................................................................................................5-4

List of Figures vii

P841C Central-Side VDSL Modem

List of Tables

Table 2-1 P841C LED Descriptions............................................................................................................................................ 2-1

Table 2-2 P841C Rear Panel Connectors .................................................................................................................................... 2-2

Table 3-1 P841C Help Commands.............................................................................................................................................. 3-4

Table 3-2 Sys Status Command .................................................................................................................................................. 3-5

Table 4-1 VDSL Default Values.................................................................................................................................................. 4-1

Table 4-2 VDSL Mode................................................................................................................................................................ 4-1

Table 4-3 VDSL Mode, Frequency Ranges and Rates................................................................................................................ 4-2

Table 4-4 VDSL Rates ................................................................................................................................................................ 4-3

Table 4-5 VDSL Status Counters ................................................................................................................................................ 4-5

Table 4-6 VDSL Show Command............................................................................................................................................... 4-7

Table 5-1 Ethernet Status Counters............................................................................................................................................. 5-2

Table 5-2 Enet Monitor Statistics................................................................................................................................................ 5-4

Table 6-1 Troubleshooting the VDSL LED.................................................................................................................................6-1

Table 6-2 Troubleshooting Data Transmission............................................................................................................................6-1

Table 6-3 Troubleshooting a Non-Constant VDSL LED ............................................................................................................6-2

Table 6-4 Troubleshooting the SYNC-rate..................................................................................................................................6-2

Table 6-5 Troubleshooting the Password ....................................................................................................................................6-2

Table 6-6 Troubleshooting Connecting to an Ethernet Switch.................................................................................................... 6-2

viii Lists of Tables

P841C Central-Side VDSL Modem

Preface

Congratulations on your purchase of the Prestige 841C Central-Side VDSL Modem.

This preface introduces you to the Prestige 841C and discusses the organization and conventions of this user’s
guide. It also provides information on other related documentation.

About VDSL

VDSL (Very high bit rate Digital Subscriber Line) is one type of DSL with very high data rates. The service can be
asymmetrical or symmetrical and can be used on the same wire as the POTS (Plain Old Telephone Service)
network and ISDN in conjunction with voice services.

About the P841C

The Prestige 841C is the ideal VDSL Line Termination (LT) modem for telephone companies. It maps one Ethernet
link to one VDSL link effectively extending Ethernet service up to 1.5km The Prestige 841C attains speeds ranging
from 1.56 Mbps to 16.67 Mbps upstream and 4.17 Mbps to 16.67 Mbps downstream at distances of up to 1.5 Km
(5,000 feet) over ordinary telephone lines.

General Syntax Conventions

• “Enter” means for you to type one or more characters and press the carriage return. “Select” or “Choose”
means for you to select one from the predefined choices.

• For brevity’s sake, we will use “e.g.” as shorthand for “for instance”, and “i.e.” as shorthand for “that is” or “in
other words” throughout this manual.

• The Prestige 841C may be referred to as the P841C throughout this manual.

Related Documentation

ZyXEL Web Site

The ZyXEL web site at www.zyxel.com contains an online glossary of networking terms and a download library
with additional support documentation.

Preface ix

P841C Central-Side VDSL Modem

Chapter 1

Getting

This chapter describes the key features, benefits and applications of your P841C.

The P841C is a VDSL Line Termination (LT) modem that is the perfect partner for the P841 VDSL subscriber
modem. It maps traffic from one VDSL (Very high bit rate Digital Subscriber Line) subscriber to one 10/100M
Ethernet that connects to a computer or LAN switch. It has built-in POTS/ISDN splitters and a console port for
local management.

to Know the P841C

1.1 Features

Compact Design With Integrated Splitters

The P841C is just 18cm x 12.6cm x 3cm (Width, Depth, Height) in size. Because of built-in POTS/ISDN splitters,
you do not have to allocate extra space for external splitters that separate voice-band and DSL signals.

10/100 Mbps Fast Ethernet Port

The 10/100 Mbps Fast Ethernet port allows you to connect it to a LAN switch.

VDSL Modes and Rates

The P841C supports the following DSLAM VDSL modes.

• 10BaseS mode giving upstream rates from 1.56 Mbps to 18.75 Mbps and downstream rates of 4.17
Mbps Kbps to 16.67 Mbps.

• ANSI Mode giving upstream rates from 1.56 Mbps to 6.25 Mbps and downstream rates of 4.17 Mbps
to 16.67 Mbps.

• ETSI Mode giving upstream rates from 1.56 Mbps to 6.25 Mbps and downstream rates of 4.17 Mbps
to 12.50Mbps.

Management

Command-line interface

System Monitoring

System status (link status, rates, statistics counters)

1.2 Application Example

The following diagram depicts a typical application of the P841C VDSL line termination modem working
together with the P841 VDSL subscriber modem in a campus setting. With the built-in splitters, VDSL service
can coexist with voice service on the same line.

Getting to Know the P841C 1-1

P841C Central-Side VDSL Modem

Figure 1-1 Campus Application

1-2 Getting to Know the P841C

P841C Central-Side VDSL Modem

Chapter 2

Hardware

This chapter gives a brief introduction to the P841C hardware.

2.1 Front Panel

The following figure shows the front panel of the P841C.

Figure 2-1 P841C Front Panel

2.1.1 Front Panel LEDs

Connections

The following table describes the LED indicators on the front panel of the P841C.

Table 2-1 P841C LED Descriptions

LED COLOR STATUS DESCRIPTION

PWR Green ON

OFF

LAN 10 M Green Blinking

ON

OFF

LAN 100 M Yellow Blinking

ON

OFF

VDSL Green Blinking

ON

OFF

The system is turned on.

The system is off.

The system is transmitting/receiving to/from a 10 Mbps Ethernet network.

The link to a 10 Mbps Ethernet network is up.

The link to a 10 Mbps Ethernet network is down.

The system is transmitting/receiving to/from a 100 Mbps Ethernet network.

The link to a 100 Mbps Ethernet network is up.

The link to a 100 Mbps Ethernet network is down.

The system is transmitting/receiving to/from the VDSL modem.

The link to the VDSL modem is up.

The link to the VDSL modem is down.

2.2 Back Panel

The following figure shows the back panel of the P841C.

Hardware Connections 2-1

P841C Central-Side VDSL Modem

Figure 2-2 P841C Back Panel

2.2.1 Rear Panel Connectors

Table 2-2 P841C Rear Panel Connectors

CONNECTER DESCRIPTION

POWER
12VDC

Connect the female end of the power adapter to the power receptacle on the rear panel of
your P841C. Connect the other end of the adapter to a power outlet.

LAN 10/100M The Ethernet interface is an RJ-45 connector. Use a crossover Ethernet cable to connect to a

hub or WAN switch. Use a straight-through Ethernet cable to connect to a computer.

CONSOLE The CONSOLE port is an RS-232 port for configuration of the P841C. Connect the male 9-pin

end of the console cable to the console port of the P841C. Connect the other end (either a
female 25-pin or female 9-pin) to a serial port (COM1, COM2 or other COM port) of your
computer. You can use an extension RS-232 cable if the enclosed one is too short.

VDSL Connect one end of a phone cable to the RJ-11 VDSL port and then connect the other end to

the telephone wall jack that connects to the subscriber’s VDSL modem (P841).

PHONE The line from the subscriber’s carries both VDSL and voice signals. The P841C has a built-in

splitter that separates the high frequency VDSL signal from the voice band signal and feeds
the VDSL signal to the P841C, while the voice band signal is diverted to the PHONE port.
Connect one end of a phone cable to the RJ-11 PHONE port and then connect the other end
to a PBX (Private Branch eXchange) or PSTN (Public Switched Telephone Network).

Make sure you are using the correct power source.

2-2 Hardware Connections

P841C Central-Side VDSL Modem

Chapter 3

Configuring

This chapter shows you how to configure and maintain your P841C using the command line interface.

the P841C

3.1 Additional Installation Requirements

In addition to the contents of the package, you need the following hardware and software components to configure
your device:

• A computer with a 10/100M Ethernet NIC (Network Interface Card)

• A computer with terminal emulation software configured to the following parameters:

 VT100 terminal emulation

 9600 bps

 No parity, 8 data bits, 1 stop bit

 No flow control

3.2 Login Screen

When you turn on your P841C, it performs several internal tests as it initializes. A login screen appears with
copyright and VDSL information prompting you to enter the password, as shown in the next figure. You need a
password to configure the P841C.

The default password when the P841C is shipped is “1234”.

ZyXEL(R) Prestige 841C VDSL-LT Modem Version V1.00(DH.0)b2 | 3/20/2002
Copyright (c) ZyXEL Communications Corp 2001-2002. All rights reserved.

VDSL Modem Code Version: 0x50
VDSL Mode: 10BaseS(0)
Reset VDSL Chip...
Password:

Figure 3-1 Login Screen

For your first login, enter the default password “1234”. As you enter the password, the screen displays an “*” for
each character you type. You see the P841C prompt after a successful login.

Password: ****

P841C>

Figure 3-2 Login Screen

If you type a wrong password, you will see the following screen.

Configuring the P841C 3-1

P841C Central-Side VDSL Modem

P841C>****
Wrong Password!

Figure 3-3 Wrong Password

You should change the default password using the passwd command.

3.3 Commands

3.3.1 General Command Conventions

References to “LT” and “NT” are common throughout the commands. “LT” means means Line Termination
(unit), which is the P841C VDSL central office side modem. “NT” means Network Termination (unit), which is
the subscriber’s VDSL modem (P841).

3.3.2 Command Syntax Conventions

• Command keywords are in regular courier font and should be typed in as they appear or in abbreviated

form (see the next section).

• Optional fields (parameters) in a command are enclosed in “[]” brackets. For example,

P841C> vdsl active [on|off]

• The “|” symbol is shorthand for the word “or”. For example,

vdsl debug [on|off]

3.4 System Related Commands

Help, exit, passwd, sys and fwupgrade are the system related commands.

3.4.1 Passwd Command

passwd

Use this command to change the login password. The default password when shipped is “1234”.

P841C>passwd
New Password: *
Retype New Password: *

P841C>

Figure 3-4 Change Password Command

Type your new password (up to 15 characters) in the New Password field and press [ENTER]. To confirm,
retype the same password in the Retype New Password field. As you enter the password, the screen displays an
“*” for each character you type. You see the P841C prompt after a successful password change.

3-2 Configuring the P841C

P841C Central-Side VDSL Modem

ZyXEL recommend you change your password after your very first login. Store your new

password in a secure place for later reference in case you forget it.

3.4.2 Exit Command

exit

Enter this command to log out. You will then have to re-enter your password to log in again.

P841C>exit

Password:

Figure 3-5 Exit Command

System Timeout

Please note that if there is no activity for longer than five minutes after you log in, your P841C will automatically
log you out. When you are logged out, press [ENTER] to bring up the password prompt.

3.4.3 help (or ?) Command

Type help or ? to show all available P841C commands as displayed in the next screen.

P841C>?
sys - display system status
help or ? - show this screen
exit - logout
passwd - change login password
fwupgrade - upgrade firmware
vdsl uprate [x] - set/show VDSL uprate
vdsl downrate [y] - set/show VDSL downrate
vdsl auto [on|off] - set/show VDSL auto rate selection flag
vdsl load [lt|nt] - load VDSL modem code
vdsl reset - reset VDSL chip
vdsl reconnect - force VDSL reconnect
vdsl status - show VDSL connect status
vdsl clear - clear VDSL connect status
vdsl debug [on|off] - set/show VDSL debug flag
vdsl monitor [on|off] - set/show VDSL monitor flag
vdsl show - show VDSL parameters setting
vdsl mode (mode) - set/show VDSL mode
vdsl active [on|off] - active/deactive VDSL port
vdsl autoupg [on|off] - set/show EEPROM auto upgrade flag
enet status - show ENET counters
enet clear - clear ENET counters
enet speed (lt|nt) (speed) - set/show NT ENET speed
enet fctrl (lt|nt) [on|off] - set/show NT ENET full duplex flow control
enet monitor [on|off] - set/show ENET monitor flag

Figure 3-6 P841C Help Commands

Configuring the P841C 3-3

P841C Central-Side VDSL Modem

Table 3-1 P841C Help Commands

FIELD DESCRIPTION

System-related Commands

sys Entering this command displays the system status.

help or ? Entering this command shows the Help screen displayed

exit Enter this command to log out of command mode.

passwd Enter this command to change the login password.

fwupgrade Enter this command to upgrade the P841C firmware.

VDSL-related Commands

vdsl uprate [x] Type this command to set the VDSL upstream rate to speed “x” or show the current upstream

speed (without “x”).

vdsl downrate [y] Type this command to set the VDSL downstream rate to speed “y” or show the current

downstream speed (without “y”).

vdsl auto [on|off] Type this command to turn the VDSL auto flag on or off or show the current VDSL auto flag

status (without “on” or “off”).

vdsl load [lt|nt] This command causes the P841C to load new VDSL modem code into LT (P841C) or NT

(P841). If LT is specified, the P841C will load the VDSL modem code into the VDSL chip. If
NT is specified, P841C will load the VDSL modem code into the P841 VDSL chip.

vdsl reset Issue this command to cause a software reset to the VDSL Chip. The VDSL link disconnects

temporarily while resetting.

vdsl reconnect Issue this command to cause the P841C to reconnect the VDSL link.

vdsl status Issue this command to show the VDSL connection status.

vdsl clear Issue this command to clear the VDSL connection status counters.

vdsl debug [on|off] Type this command to show the VDSL debug flag status (without “on” or “off”) or turn on/off

the VDSL debug flag. When this flag is set (on), VDSL debug messages are displayed.

vdsl monitor
[on|off]

vdsl show This command displays your P841C settings.

vdsl write (lt|nt)
addr value -

vdsl mode (mode) This command displays the VDSL mode if you don’t type a mode and sets it if you do.

vdsl active [on|off] Use this command to activate or deactivate VDSL.

vdsl autoupg
[on|off]

Type this command to show the VDSL monitor flag status (without “on” or “off”) or turn on/off
the VDSL monitor flag. When this flag is set (on) and the VDSL link is up, VDSL parameters
are displayed every three seconds.

Write variables to VDSL chipset registers.

Type this command to show the VDSL auto upgrade status (without “on” or “off”) or turn on/off
auto upgrade. When auto upgrade is on, the P841C will check the subscriber’s modem VDSL
version and automatically upgrade it if it is an earlier version than the P841C’s.

Ethernet-related Commands

enet status Type this command to display P841C and the subscriber’s VDSL modem’s Ethernet statistics

(if link is up).

enet clear Type this command to clear P841C and the subscriber’s VDSL modem’s Ethernet statistics (if

link is up).

3-4 Configuring the P841C

P841C Central-Side VDSL Modem

Table 3-1 P841C Help Commands

FIELD DESCRIPTION

enet speed (lt|nt)
(speed)

enet fctrl (lt|nt)
[on|off]

enet monitor
[on|off]

Type this command to set the Ethernet port speed of the P841C (you must type “lt”) or P841
(“nt”). P841C speed is displayed if you just type “enet speed”.

Type this command to set the Ethernet port full duplex flow control of the P841C (you must
type “lt”) or P841 (“nt”). P841C full duplex flow control is displayed if you just type “enet fctrl”.

Display P841C and the subscriber’s VDSL modem’s Ethernet statistics (if link is up) if this flag
is on.

3.4.4 Sys Status Command

Type sys to display the following system status parameters.

firmware version = V1.00(DH.0)b3 | 3/26/2002
VDSL modem code version = 0x50
sys uptime = 27782 ms (0:00:27.782)

Figure 3-7 Sys Status Command

Table 3-2 Sys Status Command

FIELD DESCRIPTION

firmware version This field shows the P841C firmware version and the date it was created.

vdsl modem code version This field shows the VDSL driver version.

sys uptime This field displays in milliseconds (and hours, minutes, seconds) how long the system

has been up.

3.4.5 Firmware Upgrade Command

fwupgrade

Follow these steps for a successful firmware upgrade.

Step 1. Type fwupgrade to begin the firmware upgrade process via XMODEM.

P841C>fwupgrade
This operation will overwrite the old firmware! Continue?(Y/N)

Figure 3-8 Upgrading Firmware First Warning

Step 2. Type “Y” to continue the upgrade process.

Step 3. You now see the next screen warning you not to abort the upload process after the Xmodem file

transfer begins. If you want to quit the firmware upgrade process and you have NOT YET started the
file transfer process (using a Terminal emulation program), then restart the P841C now to exit.

Configuring the P841C 3-5

P841C Central-Side VDSL Modem

You MUST NOT abort this operation after XMODEM data transfer begins.
Otherwise the device will be damaged.
Restart your device before XMODEM transfer begins to quit the upgrade process.

Figure 3-9 Upgrade Firmware Last Warning

Step 4. Launch your terminal emulation program (see next example). You should have already downloaded the

firmware and unzipped it on your computer. The firmware file has a “bin” extension. Begin the file
transfer. DO NOT interrupt it – wait until the file transfer process finishes.

If you abort the upload after the transfer begins, your device will be seriously damaged!

Example Xmodem Firmware Upload Using HyperTerminal

Click Transfer, then Send File to display the following screen.

Type the firmware file’s location, or click

Browse to look for it. The firmware file

has a “bin” extension.

Choose the Xmodem protocol.

Finally, click Send.

Figure 3-10 Example Xmodem Upload

3-6 Configuring the P841C

P841C Central-Side VDSL Modem

Chapter 4

VDSL-

This chapter shows you how to configure VDSL using Commands.

Related Commands

4.1 Introduction

VDSL-related commands supported by the P841C are shown in Table 3-1.The default values for the following
VDSL parameters are:

Table 4-1 VDSL Default Values

VDSL PARAMETER DEFAULT VALUE

VDSL Mode 0 = 10BaseS mode

VDSL Active On

VDSL Upstream Rate 12Mbps

VDSL Downstream Rate 12Mbps

4.1.1 VDSL Mode Command

vdsl mode (mode)

This command displays the VDSL mode if you don’t type a mode and sets it if you do. Use the “vdsl reset” or
“vdsl recon” command to make VDSL reconnect after you set the mode; it does not do this automatically. The
modes are listed in the next table.

P841C>vdsl mode
vdsl mode: 10BaseS(0)

Figure 4-1 VDSL Mode

Table 4-2 VDSL Mode

MODE

NUMBER

0 10BaseS mode

1 ANSI Mode (ANSI/ETSI Band Plan 998)

2 ETSI Mode (ETSI Band Plan 997)

The band plan is different for each mode even though the speed may be the same. The following table summarizes
transmission rates and frequency ranges for each VDSL mode supported by the P841C.

MODE TYPE

VDSL-Related Commands 4-1

P841C Central-Side VDSL Modem

Table 4-3 VDSL Mode, Frequency Ranges and Rates

VDSL MODE FREQ. RANGE (Hz) RATE (Mbps)

10 Base-S

Upstream 4.0M 7.9M 1.56 6.25 9.38 12.50 18.75

Downstream 900K 3.0M 4.17 6.25 8.33 12.50 16.67

ANSI Mode (ANSI/ETSI Band Plan 998)

Upstream 4.0M 5.0M 1.56 3.13 6.25

Downstream 900K 3.0M 4.17 6.25 8.33 12.50 16.67

ETSI Mode (ETSI Band Plan 997)

Upstream 4.0M 5.0M 1.56 3.13 6.25

Downstream 900K 2.7M 4.17 6.25 9.38 12.50

4.1.2 VDSL Active Command

vdsl active [on|off]

Use this command to activate or deactivate the VDSL driver.

4.1.3 VDSL Uprate and Downrate Commands

Use the following commands to view and set VDSL upstream and downstream rates. Rates vary according to
VDSL mode selected – see Table 4-4 and section 4.1.1.

Upstream Rates

vdsl uprate [uprate]

“uprate” is an integer from 0 to 4 as defined in the next table. This command sets the upstream VDSL rate if you
set a rate and displays the rate if you don’t. If you set a new rate, you must use “vdsl reset” or “vdsl reconnect”
command to reconnect.

P841C>vdsl uprate
vdsl upstream rate: 1562500 bps (0)

Figure 4-2 VDSL Upstream Rate

Downstream Rates

vdsl downrate [downrate]

“downrate” is an integer from 0 to 4 defined in the next table. This command sets the upstream VDSL rate if you
set a rate and displays the rate if you don’t. If you set the rate, you must use “vdsl reset” or “vdsl reconnect”
command to make VDSL reconnect.

4-2 VDSL-Related Commands

P841C>vdsl downrate
vdsl downstream rate: 4166667 bps (0)

Figure 4-3 VDSL Downstream Rate

Table 4-4 VDSL Rates

P841C Central-Side VDSL Modem

UPRATE/DOWN

RATE

0 1.56Mbps 4.17Mbps

1 6.25Mbps 6.25Mbps

2 9.38Mbps 8.33Mbps

3 12.50Mbps 12.50Mbps

4 18.75Mbps 16.67Mbps

0 1.56Mbps 4.17Mbps

1 3.13Mbps 6.25Mbps

2 6.25Mbps 8.33Mbps

3 12.50Mbps

4 16.67Mbps

0 1.56Mbps 4.17Mbps

1 3.13Mbps 6.25Mbps

UPSTREAM RATE DOWNSTREAM RATE

10BaseS Mode

ANSI Mode (ANSI/ETSI Band Plan 998)

ETSI Mode (ETSI Band Plan 997)

2 6.25Mbps 9.38Mbps

3 12.50Mbps

4.1.4 VDSL Auto Command

vdsl auto [on|off]

This command turns the VDSL auto flag on or off. Type vdsl auto to show the current VDSL auto flag status
(without “on” or “off”). When this flag is on, the P841C automatically negotiates upstream and downstream rates
up to the values set using the upstream and downstream commands just described.

P841C>vdsl auto
vdsl auto flag: on

Figure 4-4 VDSL Auto Flag

4.1.5 VDSL Load Command

vdsl load [lt|nt]

VDSL-Related Commands 4-3

P841C Central-Side VDSL Modem

This command makes the P841C loads new VDSL modem code into the P841C (LT) or P841 (NT). If “LT” is
specified, the P841C will load the VDSL modem code into the P841C. If “NT” is specified, the P841C will load
the VDSL modem code into the P841. The VDSL connection should automatically reconnect after the new VDSL
modem code has been successfully loaded.

4.1.6 VDSL Reset Command

vdsl reset

This command causes a software reset to the VDSL Chip (local or remote). The VDSL link first disconnects
before the channel resets.

4.1.7 VDSL Reconnect Command

vdsl reconnect

This command forcibly causes the P841C to reconnect the VDSL link.

4.1.8 VDSL Status Command

vdsl status

This command shows the VDSL status register values as shown in the next example. Information in these fields is
mainly for debugging purposes.

SNR, MSE and RS_ERR are polled every three seconds. Total RS_ERR are counted during the connection. SNR,
MSE, RS_ERR and Total_RSERR are cleared after the VDSL is link up.

P841C>vdsl status
VDSL Parameters:
LINK_STAT = 0x00 DISC = 0 Modem Code = (0x50,N/A)
VDSL Line Quality Status:
US = QAM 4/Int 32, Rate = 1562500 bps, fc = 4467773 Hz
DS = QAM 16/Int 24, Rate = 4166666 bps, fc = 1831054 Hz
US SNR = 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 dB
US MSE = 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 dB
DS SNR = 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 dB
DS MSE = 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 dB
Average US SNR = 0.00dB US MSE = 0.00dB US Noise Margin = -9.00dB
Average DS SNR = 0.00dB DS MSE = 0.00dB DS Noise Margin = -9.00dB
US RS_ERR = 0 0 0 0 0 0 0 0
US Total RS_ERR = 0
DS RS_ERR = 0 0 0 0 0 0 0 0
DS Total RS_ERR = 0
LT Power Parameters:
TXPWR = 0x32d, POCO = 0x0, POWER = 5.70 dBm, PSD = -55.27 dBm/Hz

Figure 4-5 VDSL Status Example

4-4 VDSL-Related Commands

P841C Central-Side VDSL Modem

Table 4-5 VDSL Status Counters

FIELD DESCRIPTION

VDSL Parameters: All these fields except for DISC are displayed in hexadecimal format.

LINK STAT This field displays the link status. The link is up if this field displays 0xac or 0xae; otherwise the link

is down.

DISC This is a VDSL Disconnect counter.

Modem Code This field displays information about the modem code.

VDSL Line Quality Status

US This is the VDSL UpStream rate. The constellations are QAM 4, QAM 8, QAM 16, QAM 64, QAM

256 where QAM (Quadrature Amplitude Modulation) defines how many bits there are per symbol;
for example QAM 4 means 2 bits per symbol (2

Int (Interpolation) defines how fast the symbols go through the line. It is equal to 25.0MHz / baud
rate, so for example, Int 8 = 25.0 / 8 Mbaud.

Rate is the VDSL raw speed and Fc is the carrier frequency.

DS This is the VDSL DownStream rate.

SNR The higher the SNR (Signal-to-Noise Ratio) number, the better. SNR (Signal-to-Noise Ratio is the

ratio of the amplitude of the desired signal to the amplitude of noise signals at a given point in
time).

2

), QAM 8, 3 bits (23) per symbol and so on.

MSE This is the Minimum Square Error. The minimum mean-square error (also known as MMSE)

performance measure is a popular metric for optimal signal processing.

RS_ERR This is the count of bit errors detected and corrected by Reed-Solomon code. Reed-Solomon

codes are block-based error correcting codes and are used to correct errors in many systems.

LT and NT Power Parameters

TXPWR This field displays transmission power information in hexadecimal format.

POCO Port Output Control registers provide the control bit information.

POWER This is the power measured in dBm (decibel milliwatts). It is the product of TXPWR and POCO.

PSD This is the Power Spectrum Density (power divided by bandwidth).

4.1.9 VDSL Clear Command

vdsl clear

This command clears the VDSL status counters.

4.1.10 VDSL Debug Command

vdsl debug [on|off]

This command turns the VDSL auto flag on or off or just shows the current VDSL auto flag status (without “on”
or “off”). When this flag is on, the P841C displays each stage (state) of the VDSL link initialization process.
When the VDSL link is up, no messages are displayed until the VDSL line is disconnected.

VDSL-Related Commands 4-5

P841C Central-Side VDSL Modem

0:Loading Patch to LT.............................

P841C>2:State 0 - Initialize
2: Write default parameters to LT
2: Goto State 1
3:State 1 - Wait to connect to default rate
17: Default rate connected (15230 ms)
17: VDSL:US 1.56Mbps SNR 34.08dB DS 4.17Mbps SNR 43.08dB
18: VDSL:US PSD -55.69dBm/Hz(946) DS PSD -57.00dBm/Hz(813)
18: Change Link Watchdog Timer
19: Goto State 2
19:State 2 - Check NT EEPROM patch, setup target rate
19: Remote VDSL Product Name:Prestige 841
19: NT EEPROM exists
19: NT patch signature 0x55 0x51 0x32
19: EEPROM auto upgrade disabled, skip upgrade check
19: Try to connect target rate (US:4,DS:4)
19: Write parameters to NT
23: Long Loop, Set NT M_TX = 1
24: Write parameters to LT
24: Goto State 3
25:State 3 - Wait to connect target rate
25: Target rate connected (1115 ms)
25: VDSL:US 18.75Mbps SNR 31.52dB DS 16.67Mbps SNR 43.42dB
26: VDSL:US PSD -55.69dBm/Hz(946) DS PSD -57.00dBm/Hz(813)
26: Change NT LWDT to 5 sec
26: Goto State 4
27:State 4 - Connect State
27: LT PHY Reg 0 Changed! Should be 3100, Read 0

Figure 4-6 VDSL Initialization Messages

These messages are for debugging purposes only. If you are having problems initializing the VDSL connection,
capture this screen and send it to your nearest customer support.

4.1.11 VDSL Monitor Command

vdsl monitor [on|off]

Type this command to show the VDSL monitor flag status (without “on” or “off”) or turn on/off the VDSL
monitor flag. When this flag is set (on) and the VDSL link is up, VDSL parameters are automatically displayed
every five seconds seconds.

P841C> vdsl monitor on

P841C>124:US 18.75M SNR 31.85dB RSERR 0 DS 16.67M SNR 41.08dB RSERR 0 DISC 0
127:US 18.75M SNR 31.89dB RSERR 0 DS 16.67M SNR 41.30dB RSERR 0 DISC 0
130:US 18.75M SNR 31.92dB RSERR 0 DS 16.67M SNR 41.27dB RSERR 0 DISC 0
133:US 18.75M SNR 31.78dB RSERR 0 DS 16.67M SNR 40.97dB RSERR 0 DISC 0
136:US 18.75M SNR 31.88dB RSERR 0 DS 16.67M SNR 41.10dB RSERR 0 DISC 0
139:US 18.75M SNR 31.96dB RSERR 0 DS 16.67M SNR 41.01dB RSERR 0 DISC 0
142:US 18.75M SNR 31.67dB RSERR 0 DS 16.67M SNR 41.20dB RSERR 0 DISC 0

Figure 4-7 VDSL Monitor

Refer to Table 4-5 for more information on these fields.

4.1.12 VDSL Show Command

vdsl show

4-6 VDSL-Related Commands

This command displays your P841C settings as shown in the next example.

P841C>vdsl show
vdsl mode: 10BaseS(0)
vdsl Active flag: on
vdsl Max. upstream rate: 1562500 bps (0)
vdsl Max. downstream rate: 4166667 bps (0)
vdsl state: 1
vdsl long loop flag: off
vdsl sleep mode: off
vdsl auto flag: on
vdsl monitor flag: off
vdsl debug flag: off
vdsl auto upgrade NT EEPROM flag: off
enet monitor flag: off
LT Ethernet speed: Auto
LT Ethernet full duplex flow control: on
NT Ethernet speed: Auto
NT Ethernet full duplex flow control: on
vdsl disconnect count: 0
vdsl uptime: 0 secs

Figure 4-8 VDSL Show Command

Table 4-6 VDSL Show Command

FIELD DESCRIPTION EXAMPLE

P841C Central-Side VDSL Modem

vdsl mode This field displays the VDSL mode. 10BaseS(0)

vdsl Active flag This field displays if the VDSL driver is active. on

vdsl Max. upstream rate This field displays the maximum upstream rate configured. 1562500 bps (0)

vdsl Max. downstream rate This field displays the maximum upstream rate configured. 4166667 bps (0)

vdsl state This field displays the VDSL state. VDSL goes through

1
several states before the VDSL link is up. For more
information on states, see the VDSL debug command.

vdsl long loop flag This flag comes on when the distance from the P841C to the

off
subscriber VDSL modem (P841) is greater than a certain
distance (1 Km using 24 AWG (American Wire Gauge)).
When this happens, interleaving is enabled so as to prevent
bursty errors; however this decreases throughput.

vdsl sleep mode Sleep mode means the VDSL chip is in power save mode.

off
This happens when vdsl Active is “off”.

vdsl auto flag This field shows the current VDSL auto flag status ( “on” or

on
“off”). When this flag is on, the P841C will automatically
negotiate upstream and downstream rates up to the values
set using the upstream and downstream commands.

vdsl monitor flag This field shows the current VDSL monitor flag status ( “on” or

off
“off”). When this flag is on and the VDSL link is up, the P841C
will automatically VDSL parameters every three seconds. For
more information, see the VDSL monitor command.

vdsl debug flag This field shows the current VDSL debug flag status ( “on” or

off
“off”). When this flag is on, the P841C will automatically
display messages during each stage (state) of the VDSL
initialization process. For more information, see the VDSL
debug command.

vdsl auto upgrade NT

This field shows the VDSL auto upgrade status (“on” or “off”).

off

VDSL-Related Commands 4-7

P841C Central-Side VDSL Modem

FIELD DESCRIPTION EXAMPLE

vdsl auto upgrade NT
EEPROM flag

enet monitor flag This field shows the Ethernet monitor flag status (“on” or

LT Ethernet speed This field shows the P841C Ethernet port speed. Auto

LT Ethernet full duplex flow
control

NT Ethernet speed This field shows the P841 (subscriber’s VDSL modem)

NT Ethernet full duplex flow
control

vdsl disconnect count This field displays how many times VDSL connection has

vdsl uptime This field displays how long the VDSL link has been up. 0 secs

This field shows the VDSL auto upgrade status (“on” or “off”).
When auto upgrade is on, the P841C will check the
subscriber’s modem VDSL version and automatically upgrade
it if it is an earlier version than the P841C’s.

“off”). If this flag is on and the link is up) the P841C display
P841C and the subscriber’s VDSL modem’s Ethernet
statistics.

This field shows the P841C Ethernet port flow control status
(“on” or “off”).

Ethernet port speed.

This field shows the P841 (subscriber’s VDSL modem)
Ethernet port flow control status (“on” or “off”).

been disconnected.

off

off

on

Auto

on

0

4.1.13 VDSL Autoupg Command

vdsl autoupg [on|off]

Type this command to show the VDSL auto upgrade status (without “on” or “off”) or turn on/off auto upgrade.
When auto upgrade is on, the P841C will check the subscriber’s modem VDSL modem code version and
automatically upgrade it if it is an earlier version than the P841C’s.

4-8 VDSL-Related Commands

P841C Central-Side VDSL Modem

Chapter 5

Ethernet-related

This chapter shows you how to configure Ethernet.

Commands

5.1 Introduction

The P841C has one 10/100Mbps auto-sensing Ethernet port. There are two factors related to Ethernet: speed and
duplex mode. In 10/100Mbps Fast Ethernet, the speed can be 10Mbps or 100Mbps and the duplex mode can be
half duplex or full duplex. The auto-negotiation capability makes one Ethernet port able to negotiate with a peer
automatically to obtain the connection speed and duplex mode that both ends support.

When auto-negotiation is turned on, the Ethernet port of the P841C negotiates with the peer automatically to
determine the connection speed and duplex mode. If the peer Ethernet port does not support auto-negotiation or
turns off this feature, the P841C determines the connection speed by detecting the signal on the cable and using
half duplex mode. When the P841C’s auto-negotiation is turned off, an Ethernet port uses the pre-configured
speed and duplex mode when making a connection, thus requiring you to make sure that the settings of the peer
Ethernet port are the same in order to connect.

Default Settings

The factory default settings for the Ethernet port of the P841C are:

o Speed: Auto

o Duplex: Auto

o Flow control: On for full duplex and off for half-duplex

Use a crossover Ethernet cable to connect the P841C to a switch. Use a straight-through Ethernet cable to connect
to a computer.

Ethernet-related commands supported by the P841C are shown in Table 3-1.

5.1.1 Enet Status Command

enet status

Ethernet-Related Commands 5-1

P841C Central-Side VDSL Modem

Type this command to display P841C and the subscriber’s VDSL modem’s Ethernet statistics (if link is up).

P841C>enet status
LT PHY: LSI 80225
LT Ethernet speed: Link Down!
LT Ethernet Counters:
ALGM_ERR = 0 SINGLE_COL = 0 MUL_COL = 0
LATE_COL = 0 EXC_COL = 0 MACRX_ERR = 0 CS_ERR = 0
FTL_ERR = 0 FCS_ERR = 0 OTO = 0 ORO = 0
BCF = 0 RXPAUS = 0 TXPAUS = 0 TXBCNT = 0
RXBCNT = 0 TX_DEF = 0
NT Ethernet Counters:
ALGM_ERR = 0 SINGLE_COL = 0 MUL_COL = 0
LATE_COL = 0 EXC_COL = 0 MACRX_ERR = 0 CS_ERR = 0
FTL_ERR = 0 FCS_ERR = 0 OTO = 0 ORO = 0
BCF = 0 RXPAUS = 0 TXPAUS = 0 TXBCNT = 0
RXBCNT = 0 TX_DEF = 0

P841C>

Figure 5-1 Ethernet Status

Table 5-1 Ethernet Status Counters

COUNTER MEANING

ALGM_ERR This is the number of frames received with alignment errors (odd number of nibbles).

SINGLE_COL A count of successfully transmitted frames for which transmission is inhibited by exactly one

collision.

MUL_COL A count of successfully transmitted frames for which transmission was inhibited by more than one

collision.

LATE_COL The number of times that a collision was detected on a particular interface later than 512 bit-times

into the transmission of a packet.

EXC_COL A count of frames for which transmission failed due to excessive collisions. Excessive collision is

defined as the number of maximum collisions before the retransmission count is reset.

MACRX_ERR This counter contains the number of frames received that were less than 64 bytes. These frames

are discarded.

CS_ERR The number of times that the carrier sense condition was lost or never asserted when attempting

to transmit a frame on a particular interface.

FTL_ERR This counter contains the number of frames received that were more than maximum length (1536

bytes). These frames are discarded.

FCS_ERR Frame Check Sequence Errors.

OTO A count of data and padding octets of frames that are successfully transmitted.

ORO A count of data and padding octets of frames that are successfully received.

BCF A count of frames that are successfully received and are directed to the broadcast group address.

RXPAUS The number of received PAUSE packets.

TXPAUS The number of PAUSE packets transmitted.

TXBCNT This counter indicates the number of valid data frames that have been transferred over the

transmit channel.

RXBCNT This counter indicates the number of valid data frames that have been transferred over the

receive channel.

TX_DEF A count of frames for which the first transmission attempt was delayed because the Ethernet

media was busy.

5-2 Ethernet-Related Commands

P841C Central-Side VDSL Modem

5.1.2 Enet Clear Command

enet clear

Type this command to clear P841C and the subscriber’s VDSL modem’s Ethernet statistics (if link is up).

5.1.3 Enet Speed (lt|nt) (speed) Command

enet speed (lt|nt) (speed)

Type this command to set the Ethernet port speed of the P841C (with “lt”) or P841 (with “nt”). P841C speed is
displayed if you just type “enet speed”.

P841C>enet speed
enet speed(LT): Auto

Figure 5-2 Ethernet Speed

Speed index number Speed/Flow Control

0 Auto Negotiation

1 10 Mbits/s, Half Duplex

2 10 Mbits/s, Full Duplex

3 100Mbits/s, Half Duplex

4 100Mbits/s, Full Duplex

5.1.4 Enet full duplex Fctrl (lt|nt) [on|off] Command

enet full duplex fctrl (lt|nt) [on|off]

Type this command to set the Ethernet port flow control or show the Ethernet port flow control status (without
“on” or “off”). By default, flow control is on for full duplex Ethernet connections and off for half duplex Ethernet
connections.

P841C>enet fctrl
enet full duplex flow control(LT): on

Figure 5-3 Ethernet Flow Control

5.1.5 Enet Monitor [on|off] Command

enet monitor [on|off]

Ethernet-Related Commands 5-3

P841C Central-Side VDSL Modem

When this flag is on this command automatically displays the P841C (and the subscriber’s VDSL modem’s
Ethernet statistics if the link is up) every five seconds. Enter the command without “on” or “off” to just show the
Ethernet monitor status.

P841C>enet monitor
enet monitor flag: off

Figure 5-4 Ethernet Monitor Status

P841C>enet mon on

P841C>108:Enet(LT):Tx(F:0 B:0 S:0) Rx(F:681 B:85833 S:1950)
109:Enet(NT):Tx(F:694 B:90140 S:2709) Rx(F:0 B:0 S:0)
113:Enet(LT):Tx(F:0 B:0 S:0) Rx(F:815 B:117449 S:6323)
114:Enet(NT):Tx(F:828 B:119529 S:5877) Rx(F:0 B:0 S:0)
118:Enet(LT):Tx(F:0 B:0 S:0) Rx(F:876 B:125667 S:1643)
119:Enet(NT):Tx(F:884 B:126557 S:1405) Rx(F:0 B:0 S:0)
123:Enet(LT):Tx(F:0 B:0 S:0) Rx(F:934 B:134174 S:1701)
124:Enet(NT):Tx(F:943 B:134941 S:1676) Rx(F:0 B:0 S:0)
128:Enet(LT):Tx(F:0 B:0 S:0) Rx(F:980 B:138422 S:849)

P841C>enet mon off
129:Enet(NT):Tx(F:989 B:139256 S:863) Rx(F:0 B:0 S:0)

Figure 5-5 Enet Monitor Statistics

Table 5-2 Enet Monitor Statistics

LABEL DESCRIPTION

LT The P841C VDSL modem.

NT The subscriber’s VDSL modem (P841).

TxF and RxF Transmitting and Receiving Frame count.

TxB and RxB Transmitting and Receiving Byte count.

TxS and RxS Transmitting and Receiving Throughput in Bytes per second.

5-4 Ethernet-Related Commands

P841C Central-Side VDSL Modem

Chapter 6

Troubleshooting

This chapter covers potential problems and possible remedies. After each problem description, some

steps are provided to help you diagnose and solve the problem.

6.1 VDSL LED

The VDSL LED is not on.

Table 6-1 Troubleshooting the VDSL LED

STEPS CORRECTIVE ACTION

1 Disconnect the phone wire coming from the VDSL port of the P841C and connect the subscriber’s VDSL

modem or router directly to the VDSL port of the P841C using a different telephone wire.

If the LED turns on, check for a problem with the building’s phone wire.

2 Set the VDSL modem to “auto-negotiate”. If this is not possible, set it to 100 Mbps, half duplex mode.

3 Use the VDSL commands to reset and reconnect the VDSL channel (see sections 4.1.6 and 4.1.7).

4 Log into the P841C, enter the VDSL debug command (see section 4.1.10), take screen shots of this

information and send it to your nearest customer support representative.

5 If the LED remains off, contact the distributor.

6.2 Data Transmission

The VDSL LED is on, but data cannot be transmitted.

Table 6-2 Troubleshooting Data Transmission

STEPS CORRECTIVE ACTION

1 Disconnect the phone wire coming from the VDSL port of the P841C and connect the VDSL modem or

router directly to the VDSL port of the P841C using a different telephone wire.

If data can be transmitted, check for a problem with the building’s phone wire.

2 Check to see that you are using the correct VDSL mode (see section 4.1.1).

3 Use the VDSL commands to reset and reconnect the VDSL channel (see sections 4.1.6 and 4.1.7).

4 Connect the VDSL modem or router to another P841C (VDSL port).

If the VDSL modem or router works with a different P841C, then there may be a problem with the original
P841C. Contact the distributor.

5 If using a different P841C does not work, try a different subscriber VDSL modem or router with the

original P841C.

6 Log into the P841C, enter the VDSL status command (see section 4.1.8) and the VDSL debug command

(see section 4.1.10), take screen shots of this information and send it to your nearest customer support
representative.

Troubleshooting 6-1

P841C Central-Side VDSL Modem

6.3 Intermittent VDSL LED

A VDSL LED turns on and off intermittently.

Table 6-3 Troubleshooting a Non-Constant VDSL LED

STEPS CORRECTIVE ACTION

1 Disconnect the phone wire coming from the VDSL port of the P841C and connect the subscriber’s VDSL

modem or router directly to the VDSL port of the P841C using a different telephone wire.

If the VDSL LED stays on, check for a problem with the building’s phone wire.

2 Use the VDSL commands to reset and reconnect the VDSL channel (see sections 4.1.6 and 4.1.7).

6.4 Data Rate

The SYNC-rate is not the same as the configured rate.

Table 6-4 Troubleshooting the SYNC-rate

STEPS CORRECTIVE ACTION

1 Disconnect the phone wire coming from the VDSL port of the P841C and connect the subscriber’s VDSL

modem or router directly to the VDSL port of the P841C using a different telephone wire.

If the rates match, the regular phone wire quality may be limiting the speed.

2 Use the VDSL commands to reset and reconnect the VDSL channel (see sections 4.1.6 and 4.1.7).

3 Log into the P841C, enter the VDSL status command (see section 4.1.8) and the VDSL debug command

(see section 4.1.10), take screen shots of this information and send it to your nearest customer support
representative.

6.5 Password

I forgot the password to my P841C.

Table 6-5 Troubleshooting the Password

STEPS CORRECTIVE ACTION

1 Contact your distributor for a “generic password”. Tell them your product serial number (located on the

sticker on the bottom of the P841C) and firmware version you are using (see section 3.4.4).

6.6 Connecting to an Ethernet Switch

The P841C cannot connect to an Ethernet switch.

Table 6-6 Troubleshooting Connecting to an Ethernet Switch

STEPS CORRECTIVE ACTION

1 Check your cable connections. Use a crossover Ethernet cable to connect to a hub or an Ethernet switch.

(Use a straight-through Ethernet cable to connect to a computer.)

2 The factory default settings for the Ethernet port of the P841C are:

6-2 Troubleshooting

P841C Central-Side VDSL Modem

Table 6-6 Troubleshooting Connecting to an Ethernet Switch

STEPS CORRECTIVE ACTION

 Speed: Auto

 Duplex: Auto

 Flow control: On for full duplex and off for half-duplex

If the P841C’s auto-negotiation is turned off, an Ethernet port uses the pre-configured speed and duplex
mode when making a connection, thus requiring you to make sure that the settings of the switch Ethernet
port are in the same order to connect.

Troubleshooting 6-3

P841C Central-Side VDSL Modem

Power Adapter Specifications

NORTH AMERICA

AC Power Adapter model AD48-1201200DUY AC Power Adapter model DV-121A2-5720

Input power: AC120Volts/60Hz/0.25A Input power: AC120Volts/60Hz/27VA

Output power: DC12Volts/1.2A Output power: DC12Volts/1.2A

Power consumption: 6 W Power consumption: 6 W

Safety standards: UL, CUL (UL 1950, CSA C22.2
No.234-M90)

EUROPE UNITED KINGDOM

AC Power Adapter model AD-1201200DV AC Power Adapter model AD-1201200DK

Input power: AC230Volts/50Hz/0.2A Input power: AC230Volts/50Hz/0.2A

Output power: DC12Volts/1.2A Output power: DC12Volts/1.2A

Power consumption: 6 W Power consumption: 6 W

Safety standards: TUV, CE (EN 60950) Safety standards: TUV, CE (EN 60950, BS7002)

JAPAN AUSTRALIA AND NEW ZEALAND

AC Power Adapter model JOD-48-1124 AC Power Adapter model AD-1201200DS or AD-121200DS

Input power: AC100Volts/ 50/60Hz/ 27VA Input power: AC240Volts/50Hz/0.2A

Output power: DC12Volts/1.2A Output power: DC12Volts/1.2A

Power consumption: 6 W Power consumption: 6 W

Safety standards: T-Mark (Japan Dentori) Safety standards: NATA (AS 3260)

Safety standards: UL, CUL (UL 1310, CSA C22.2 No.223­M91)

Power Adapter Specifications A

P841C Central-Side VDSL Modem

Index

1

10 Base-S .................................................4-8

10Base-S ...........................................4-7, 4-9

10Base-S Mode ........................................ 1-1

A

ALGM_ERR ............................................5-2

ANSI Mode .............................................. 1-1

ANSI/ETSI Plan 998................................4-8

B

Back Panel................................................2-1

Band plan .................................................4-7

BCF ..........................................................5-2

C

DISC ...................................................... 4-11

Disclaimer ................................................... ii

DS .......................................................... 4-11

Duplex....................................... 5-1, 5-3, 6-3

E

enet fctrl ................................................... 3-5

enet monitor ......................................3-5, 5-3

enet speed..........................................3-5, 5-3

enet status..........................................3-4, 5-1

Ethernet Switch........................................ 6-2

ETSI Mode...............................................1-1

ETSI Plan 997 ...................................4-8, 4-9

EXC_COL................................................ 5-2

Exit........................................................... 3-3

CE............................................................... iv

Certification ............................................... iv

Class B .......................................................iv

CONSOLE ...............................................2-2

Contacting Customer Support ..................... v

Copyright ....................................................ii

CS_ERR ................................................... 5-2

Customer Support........................................ v

D

Data Rate..................................................6-2

Data Transmission.................................... 6-1

Declaration of Conformity ......................... iv

Default Settings

Ethernet .............................................. 5-1

F

FCC ............................................................ iv

FCC Rules.................................................. iv

FCS_ERR................................................. 5-2

Federal Communications Commission (FCC)

Interference Statement ........................... iv

Firmware Upgrade ...................................3-5

Flow control .............................. 2-1, 5-1, 6-3

Front Panel ............................................... 2-1

Front Panel Connectors............................2-2

Front Panel LEDs..................................... 2-1

FTL_ERR................................................. 5-2

fwupgrade ................................. 3-2, 3-4, 3-5

H

help........................................................... 3-3

Index C

P841C Central-Side VDSL Modem

I

Intermittent VDSL LED ...........................6-2

Introducing the SMT ................................3-1

L

LAN 10/100M ..........................................2-2

LATE_COL ..............................................5-2

Line Termination (LT)........................ ix, 1-1

LINK STAT ............................................4-11

Login Screen ............................................3-1

long loop.................................................4-13

M

MACRX_ERR..........................................5-2

Modem Code ..........................................4-11

MSE........................................................4-11

POWER..................................................4-11

Power Adapter............................................ A

PSD ........................................................4-11

PWR .........................................................2-1

R

Rear Panel Connections

Rear Panel .......................................... 2-2

reconnect ..................................................3-4

Related Documentation .............................. ix

repair ..........................................................iii

RS_ERR .................................................4-11

RXBCNT..................................................5-2

RXPAUS ..................................................5-2

S

MUL_COL ...............................................5-2

N

Network Interface Card ............................3-1

NIC ................... See Network Interface Card

NT (Network Termination ........................3-2

O

ORO .........................................................5-2

OTO..........................................................5-2

P

P841..........................................................1-1

P841C .........................................................ix

Passwd......................................................3-2

Password.................................... 3-1, 3-2, 6-2

PHONE.....................................................2-2

POCO .....................................................4-11

Service........................................................iii

Services ....................................................... v

SINGLE_COL..........................................5-2

sleep mode..............................................4-13

SNR ........................................................ 4-11

Splitters

Integrated Splitters ............................. 1-1

SYNC-rate................................................6-2

Syntax Conventions....................................ix

Sys Status .................................................3-5

system related commands.........................3-2

System Timeout........................................3-3

T

Terminal emulation ..................................3-1

Terminal Emulation..................................3-1

TX_DEF...................................................5-2

D Index

P841C Central-Side VDSL Modem

TXBCNT.................................................. 5-2

TXPAUS................................................... 5-2

TXPWR.................................................. 4-11

U

US........................................................... 4-11

V

VDSL .......................................................1-1

VDSL ......................................................... ix

vdsl active ................................. 3-2, 3-4, 4-8

vdsl debug ...................... 3-2, 3-4, 4-11, 4-13

vdsl downrate ...........................................3-4

VDSL LED...............................................6-1

vdsl mode ................................ 3-4, 4-7, 4-13

VDSL Mode......................................4-7, 4-8

VDSL Modes ........................................... 1-1

VDSL Rates ......................................4-8, 4-9

vdsl show ........................................3-4, 4-12

vdsl status........................................3-4, 4-10

vdsl uprate................................................ 3-4

VT100 ...................................................... 3-1

Z

ZyXEL Limited Warranty .......................... iii

Note...................................................... iii

ZyXEL Web Site ........................................ ix

Index E