


<<< Question US1 >>> General
How do I know what version of the ROM's I have in my modem???

<<< Answer US1 >>>
If you have a U-1496 or a U-1496 plus, you can access your "product information"
screen via the front-panel menu tree.  For all models, you can type "ATI" from
aterminal program to display the information.

          Example:  U-1496E  V 6.12 M

If the response from an "ATI" is "1496", then you have ROM version 6.x, in which
case, you should type "ATI1". This shows you the model of the modem you have,
and also the version of ROM's that are installed.  The character (M or K) after
the number indicates which type of chip you have.  An M means you have a 1
Megabit set of EPROMS, while a K indicates 512k EPROMS. (1 Megabit ROMs are
required for 16.8K bps or voice capability) plus models will show a P after the
chip type.

<<< Question US2 >>> General
How do I get my software to work with my ZyXEL modem???

Most communications software has our modem listed in their "auto-config" list.
If not, we have an area (file area 1: Application Driver Area) on our BBS
devoted to such drivers.

In general though, the following example will get the majority of terminal
programs functioning:

     1. Initialization string = ATZ
     2. DTE speed = 38400
     3. Auto baud detect = OFF
     4. Hardware flow control (RTS/CTS) = ON
     5. Software flow control (XON/XOFF) = OFF

<<< Question US3 >>> S/W
Can I use ZFAX under Windows???

<<< Answer US3 >>>
No, ZFAX does not work properly under windows.  To take advantage of all that
windows offers, we recommend you use one the many software packages designed
exclusively for Windows.

<<< Question US4 >>> General
The information in the User's Manual conflicts with the information on the Quick
Reference Guide.  Which is correct???

<<< Answer US4 >>>
Due to recent feature enhancements, and the time it takes to print manuals, the
Quick Reference Guide should be considered the ultimate authority. For each
newer version firmware, the firmware release note contains the newest
information. The latest firmware release note can be retrieved from file area
7: Release Note Area on our BBS.



<<< Question US5 >>> General
What kind of blank EPROM's should I use when burning my own EPROM's???

<<< Answer US5 >>>
512k  : Use 27C512 EPROMS.  They should be at least 150ns
1 Meg : Use 27C010 EPROMS.  They should be at least 150ns; 120 is
        recommended.
On the plus models, you MUST use 100ns chips.

<<< Question US6 >>> General
A. What is a 16550 UART chip???
B. What will it do for me???
C. How do I install one???

<<< Answer US6 >>>
A. It is a 16550 Universal Asynchronous Receiver/Transmitter chip, which is
   located on your serial card or internal modem.  This chip controls the flow
   of data into and out of your computer.

B. The major advantage of the 16550 over the 16450 is that it has a 16 byte
   buffer (as opposed to 1 byte).  This is useful in multitasking environments
   (such as Windows or OS/2), when your CPU might be busy doing other tasks
   (e.g. serving hard drive), and the modem is receiving data. In this case,
   the buffer would store the data until the CPU could serve the serial port.
   This makes high speed communication more reliable and multitasking more
   efficient.

C. The 16550 is pin-compatible with the 16450.  Before buying the chip, verify
   that your serial card has a socketed UART.  You need to unplug the current
   chip and replace it with the 16550.  If it is soldered to the board, you will
   need to buy a new board.  Some software will automatically recognize the
   16550, others have a setting in the configuration section to enable the
   buffer.

<<< Question US7 >>> General
My modem will transmit and receive data, but not faxes.  What should I do???

<<< Answer US7 >>>
Verify that the fax software you are using is installed properly, and that it
is set to use a Class 2 or Class 2.0 modem/fax.  Try using a different remote
fax machine for testing purposes. The remote machine must be Group 3 compatible.
Try testing the modem with Zfax and see if the problem persists.

<<< Question US8 >>> General
What is caller ID?  The caller ID function on my modem does not seem to be
working. What should I do???

<<< Answer US8 >>>
Caller ID is a service offered by the telephone company which will deliver the
calling party's phone number between the first and second ring.  Make sure that
you have caller ID enabled on your telephone (you must subscribe to the service
through your phone company.)  To enable the modem, turn on bit 2 of register S40
by issuing the command ATS40.2=1.



<<< Question US9 >>> General
I notice that I get lots of T401 and T402 time outs, but the User's Manual says
that I should not get any. What's wrong???

<<< Answer US9 >>>
The T401 and T402 timers are used in MNP 4 and V.42 connections. The "T401
timeout" indicates the number of resent blocks, due to not receiving an
acknowledgement in the alloted time.  The T401 timeout is just one of the
reasons for blocks being resent, so T401 timeouts will not necessarily be equal
the "blocks resent" value in a link status report.

The "T402 timeout" indicates the number of frames sent due to inactivity. These
are sent to keep the link active, and assures the other modem that the
connection is still there.  This number steadily increases, especially during a
relatively "light" interactive dialup session.

<<< Question US10 >>> General
My modem will not connect to modem "XYZ". What should I do???

<<< Answer US10 >>>
Verify that your software is configured properly.  Check to see if your modem
will connect to other kinds of modems.  In order to diagnose the problem, it is
necessary to know the make and model of the remote modem, as well as what speed/
protocol you are attempting to connect at. After a failed connect, capture the
link status report (ATI2).  Call technical support, and we will attempt to
reproduce the problem.

<<< Question US11 >>> S/W
Zfax will not answer the phone.  What should I do???

<<< Answer US11 >>>
Make sure that Zfax is configured properly, particularly that the ring counter
is set to 1 or more.  Verify that the DTR light on your modem is on.  Does the
AA light flash when the phone rings???

<<< Question US12 >>> General
What is distinctive ring, and how do I use it???

<<< Answer US12 >>>
Distinctive ring allows you to use one phone line to route calls to specific
devices (such as fax, answering machines, and modem).  This is accomplished by
the phone company when they assign multiple phone numbers to a single line. The
ring pattern is altered on each of these numbers (length of ring, and time
between rings) to allow the devices to distinguish between the 4 available ring
patterns.  One of the most common uses would be that of a single line sysop who
wants to operate a BBS on the same line as his voice calls.  The modem can be
configured to only answer the proper calls.

<<< Question US13 >>> General
What is Extended Distinctive Ring (EDR), how do I use it???



<<< Answer US13 >>>
ZyXEL's Extended Distinctive Ring capability lets the modem monitor a call
answered by someone or something else (e.g., an answering machine) and then
conditionally pick up depending on what is heard.  When EDR is enabled, the
modem will wait for the phone to ring, then wait for the ringing to stop, then
(still without picking up) listen for the particular DTMF (0, #, and *) and CNG
(FAX) signals you've selected.  The modem will only pick up (go off hook) if an
appropriate signal is heard. This capability allows you to have one phone line
and phone number and a mix of equipment yet still be able to have the modem
answer only those voice/data/fax calls you want it to. E.g., if you pick up a
phone and find it is a fax call, you can press "*" and hang up and let the modem
listening on the same line answer the call.

<<< Question US14 >>> General
I can't get a 16.8Kbps connection. Is there something wrong with my modem???

<<< Answer US14 >>>
Check the version of ROM's that are in your modem. 16.8Kbps is possible with ROM
version 5.01 M or above. Both modems must be ZyXEL, and have the proper ROMs
installed. In addition, the signal to noise ratio on the phone line must be high
enough to support the connection.

<<< Question US15 >>> General
I can't get a 19.2K bps connection.  Is there something wrong with my modem???

<<< Answer US15 >>>
19.2 is available only on plus models equipped with rom version 6.00 or above.
Both modems must be ZyXEL plus models, and have the proper roms installed.  In
addition, the signal to noise ratio on the phone line must be high enough to
support the connection.

<<< Question US16 >>> General
My supervisory password doesn't seem to work.  What should I do???

<<< Answer US16 >>>
The factory setting for the supervisory password is "ZyXEL".  If this has been
changed, and you don't know what it is, you can do a hardware reset to get to
the factory default. If you set S35.6=1 on profile 0 then the password is
protected. You have to return the modem to get the password reset or you can
use an old version that does not have password protection feature get to do a
hardware reset.

<<< Question US17 >>> General
What is the difference between Class 2 and Class 2.0???

<<< Answer US17 >>>
Class 2 is based on the draft (SP-2388) of the standard.  Class 2.0 is the
"official" standard (EIA/TIA-592).  There were differences of opinion as to how
certain features of Class 2 should work, which caused compatibility problems
between modems and software. Class 2.0 should eliminate that problem. Class 2
commands are generally characterized by +Fxxx, and Class 2.0 commands follow
the +Fxx format. ZyXEL ROM release 6.12 and greater supports both Class 2 and
Class 2.0.



<<< Question US18 >>> General
Will my ZyXEL modem work with ABC fax program or with brand XYZ fax machine???

Yes, if the software supports Class 2 or Class 2.0 commands. Fax machines must
be Group 3 compatible to send and receive from your ZyXEL modem/fax.

<<< Question US19 >>> General
I am having problems connecting my ZyXEL modem with a UNIX system.  What should
I do???

<<< Answer US19 >>>
Verify that the S38 register is set to 8, and that you have software flow
control enabled (&H4).  Due to the differences between all of the flavors of
UNIX, we recommend you consult your software vendor for detailed instructions
for high speed modems.

<<< Question US20 >>> General
I am using Frontdoor/Binkley Term/ D'Bridge/etc. with RCVFAX and a BBS program.
I am having problems receiving faxes, connection messages, etc. What should I
do???

<<< Answer US20 >>>
Make sure that you have the program configured correctly.  Refer to our setup
instructions on our BBS file area 1: Application Driver Area (ZYX1496E.MCF) for
detailed instructions.

<<< Question US21 >>> General
What is the latest version of ROM's?  How do I get them???

We update our BBS with the latest ROM code.  If you have your own EPROM burner,
you can download these files (refer to page 15-16 <Rev. 2.1> or page 17-10
<Rev.2.2> of your user's manual for more information on these files.)

<<< Question US22 >>> General
What is the difference between a 1496E and a 1496E plus (or 1496 and 1496 plus)?

<<< Answer US22 >>>
The plus models support higher speeds (including 19.2Kbps), as well as the CELP
advanced voice compression method. Now all 1496 model is a plus model, also
called 1496S+ (S Plus).

<<< Question US23 >>> General
What is the difference between a 1496 (or 1496S) and a 1496E???

<<< Answer US23 >>>
The 1496, also called 1496S, has an LCD front panel display, which shows
connection information, as well as line-condition monitoring.  The menu tree is
operated by the four front panel keys.  It also supports 4-wire leased line,
with several associated protocols.  Aside from these differences, the two models
are identical in features and protocols.



<<< Question US24 >>> General
I have a User's Manual, but it doesn't give any information about ZFAX. Is there
any documentation for ZFAX?

<<< Answer US24 >>>
Yes, on the ZFAX disk, there is a file called ZFAX.MNU, which contains the full
manual for ZFAX.

<<< Question US25 >>> General
Will ZyXEL implement V.32terbo???

<<< Answer US25 >>>
V.32terbo is not a CCITT (ITU-TSS) standard, and does not perform as well as
19.2 ZYX.  We will have to see a greater popularity of V.32terbo to support it.

<<< Question US26 >>> General
Will my ZyXEL modem connect to a USR Dual Standard at 16.8 Kbps???

<<< Answer US26 >>>
No, USR uses their proprietary HST method which is asymmetrical (can only send
data one way at 16.8Kbps).  The ZyXEL 16.8Kbps protocol will transfer data
between two ZyXEL modems symmetrically (16.8Kbps BOTH ways).  The highest
connect rate between a ZyXEL and a USR Dual Standard is 14.4 Kbps.

<<< Question US27 >>> S/W
What is the latest version of Zfax???

<<< Answer US27 >>>
Currently, the latest version is 3.12.  You can obtain this, or later versions
by calling our BBS and downloading the file ZFAX312E.ZIP.

<<< Question US28 >>> General
How does the modem record my voice, and where does it store it???

<<< Answer US28 >>>
Using ADPCM, the modem samples your voice (analog) 9600 times per second.  It
converts each of those values to a digital value, and sends it through the
serial port to your computer, where it is stored on your hard drive.  When you
choose to play audio, the digital data is sent back through the serial port to
the modem, which then converts it back into an analog waveform.

<<< Question US29 >>> General
What are the voice capabilities of the modem?  How do I record a message???

<<< Answer US29 >>>
All ZyXEL modems with 5.01 M and above ROM's will send and receive voice
messages.  Zfax has a voice configuration section, where you can set the type
of recording (2, 3 or 4-bit ADPCM, or CELP).  Only the plus models can use the
CELP method.  You can record a message from another phone line or by using a
telephone handset plugged into the modem 'LINE' jack (be sure to talk into the
EARPIECE).  Refer to the Zfax manual for more detailed instructions. You can
also use your telephone plugged through a ZyXEL voice switch box to the modem
to play and record voice messgae. Refer to user's manual Rev. 2.2 page 15-20.



<<< Question US30 >>> General
What is the DTMF detection feature of the voice mode? Can I use it while
recording a message???

<<< Answer US30 >>>
Dual Tone Multiple Frequency (DTMF) tones are the buttons on your telephone
(1-9,* #).  The modem recognizes each of these tones and sends the corresponding
digit in the data stream to the computer.  These tones can be embedded within a
voice message.  An example of their use would be in Zfax, you can enter a
password to retrieve your messages remotely.

<<< Question US31 >>>
Does ZyXEL modems support V.34???

<<< Answer US31 >>>
Yes, ZyXEL is currently working on a new generation of modems to support V.34
and ISDN.  The feature set has not been released yet.  These new modems are
expected to be available by the end of the 3rd quarter 1994.

<<< Question US32 >>> General
Will ZyXEL support V.FC???

<<< Answer US32 >>>
At the present time, we are working on the V.34 28.8K standard, we will later
consider the issue of supporting V.FC (Rockwell's proprietary 28.8K modulation
method).

<<< Question US33 >>> General
Will users who choose not to upgrade to the new modems be able to upgrade to
partial V.34 support?

<<< Answer US33 >>>
It is possible to implement SOME of the fallback speeds of V.34 by just firmware
upgrading existing modems, but due to hardware limitations, full support is
impossible. A partial speed implementation of V.34 would not allow V.34
compatibility. We have to put this issue aside for the time being.

<<< Question US34 >>> General
What are the minimum system requirements for VoiceFax???

<<< Answer US34 >>>
     DOS:
     386SX-20
     640k system RAM
     40 MB hard drive
     16550 equipped I/O card
     DOS 3.3
     ZyXEL modem with 5.x M ROMs

     Windows:
     386DX-25
     4 MB system RAM
     40 MB hard drive
     16550 equipped I/O card
     Windows 3.0
     ZyXEL modem with 5.x M ROMs



     Mac:
     68000 (16Mhz)
     System 6.07
     1 MB RAM
     40 MB hard drive
     ZyXEL modem with 5.x M ROMs

<<< Question US35 >>> S/W
Can I use caller-ID and distinctive ring with a voice program???

<<< Answer US35 >>>
The DOS version of VoiceFax incorporates both Caller-ID and distinctive ring.
It also includes a Terminate and Stay Resident (TSR) program which allows you
to see who is calling without running the voice software.

<<< Question US36 >>> S/W
Can the VoiceFax software autodetect voice/fax/data???

<<< Answer US36 >>>
Yes, the DOS version will allow you leave voice/fax/data messages in mailboxes,
and also allows you to use your choice of data communication software.

<<< Question US37 >>> General
What is the U-1496P modem???

<<< Answer US37 >>>
The U-1496P is a portable, dual function modem for land and cellular
communications.  The modem weighs 14 ounces, and measures 7.8" x 2.8" x 1.0".
In addition to the cellular feature, the U-1496P also has all the standard
features of the U-1496 series, such as data/fax/voice capabilities, at up to
16.8 Kbps.

<<< Question US38 >>> General
What is the ZyCellular mode???

<<< Answer US38 >>>
ZyXEL's ZyCellular is a special modulation mode that was developed for data
communications over analog cellular link.  It is ideal for use in either a
mobile unit or on a desktop. Special ZyCellular features include:
     *    Asynchronous and Synchronous communications at speeds up to 14.4 Kbps
     *    Enhanced reliability with low bit error rate
     *    Dual function for land and cellular communications
     *    Auto cellular mode detection and switching
     *    Auto dial-up speed detection and switching
     *    Auto optimum error control selection and switching
     *    V.42 error control with selective reject
     *    Cellular enhanced performance: CELL 14,400, 12,000, 9600, 7200, 4800

<<< Question US39 >>> General
What are the key technologies used in the ZyCellular mode???



<<< Answer US39 >>>
ZyXEL's ZyCellular mode incorporates four proprietary technologies, made
especially for cellular networks, to provide reliable data communication without
the additional overhead.  These four technologies work to provide enhanced
throughput with extremely low bit error rates over cellular channels -- unique
to ZyXEL's ZyCellular modem.

     FRS:   Fast Re-Synchronization of the modem after cell hand-off or power
            level change.

     DCSS:  Dynamic Cellular Speed Selection dynamically selects the best
            operating speed and mode in order to minimize errors and maximize
            throughput.

     ATPA:  Automatic Transmit Power Adjustment selects optimum transmit power,
            inorder to avoid saturating the cellular channel.

     RHE:   Reliable Handshake Enhancements.  This feature enables ZyCellular to
            handshake reliably without retry, whereas other modems might have to
            retrytwo or three times even during a handshake.

<<< Question US40 >>> General
Does ZyXEL have a special version of firmware for the U-1496P??? What kind of
EPROMs are used???

<<< Answer US40 >>>
Yes, ZyXEL developed a unique version of firmware with the CP suffix, for
example: RM620CP.U12 and RM620CP.U13.

1 Megabit EPROM chips, in a PLCC package are used. Later shipments of P model
used 29F010 1M Flash EPROM chips soldered on the modem PCB.

<<< Question US41 >>> General
What is the difference between MNP 10 and ZyCellular???

<<< Answer US41 >>>
ZyXEL's ZyCellular incorporates proprietary technologies that are used to
strengthen the physical layer of the transmission in order to handle the most
common impairments encountered in cellular networks. Changes in the cellular
network occur very quickly.  A protocol such as MNP 10 is not as effective
because it must receive several error blocks before any corrective action is
taken.  By the time a MNP 10 modem reacts, the error condition may have already
disappeared.  It is a link layer protocol, which means that it tries to correct
the errors after the data has been received.

<<< Question US42 >>> General
Can existing ZyXEL modems have the ZyCellular option added???

<<< Answer US42 >>>
Yes, all ZyXEL modems can have this feature added.  Beginning with ROM version
6.12, ZyCellular is a standard feature.



<<< Question US43 >>> General
What are the standard accessories for the U-1496P???

<<< Answer US43 >>>
The package consists of:

     U-1496P modem
     110V (or 220V) power adaptor
     RJ-11 cable
     User's manual

     Optional Accessories:

     12V battery with cable
     Cigarette lighter adaptor

<<< Question US44 >>> General
What power options are available for the U-1496P???

<<< Answer US44 >>>
The modem can be powered by the AC adapter (included), or by the optional 12V
battery, or optional cigarette lighter adaptor.

<<< Question US45 >>> General
What other equipment do I need to use ZyCellular???

<<< Answer US45 >>>
A cellular phone with a tip/ring interface (commonly callled RJ-11 jack) is
needed. This provides the modem with the proper connection to your cellular
phone.  Each cellular phone vendor has different options, and there are several
third-party manufacturers of tip/ring interfaces.  You should consult with your
cellular phone dealer to locate the suitable adapter for your brand of phone.

<<< Question US46 >>> General
What is Selective Reject???

<<< Answer US47 >>>
Beginning with ROM version 6.10, ZyXEL modems implement selective reject (SREJ).
When an error is encountered, only the corrupted data is re-sent. It saves
retransmission time, because most V.42 modems would resend the bad frame, as
well as all subsequent frames that were previously sent.  In poor line
conditions, this feature will result in higher throughput.

<<< Question US48 >>> General
How do I know if selective reject is "on"?

<<< Answer US48 >>>
When you connect with another SREJ-equipped modem, the connect message you
receive will be something similar to:

     CONNECT 57600/ZyX  19200/V42b/SREJ



<<< Question US49 >>> General
How do I configure my 1496 series modem for use with Unix???

<<< Answer US49 >>>
Due to the number of different flavors of Unix, it is impossible to detail the
setup for each here. In general though, the following init string will work for
inbound dialing: ATQ2E0S0=3. You should also lock the DTE speed using the S18
register (see manual or QRG for more info on values).

NOTE: Make sure that the software and modem agree on flow control (generally set
      in "gettydefs" file.) outbound dialing requires a dialer file, which can
      contain send/expect scripts, or AT commands for a binary dialer program.

<<< Question US50 >>> General
I have my modem configured for dial-in use on a Unix system, but when I call,
all I see is "garbage", why???

<<< Answer US50 >>>
Make sure you set S18.  The modem defaults to 38.4, or whatever the last AT
command was sent at.  Locking S18 tells the modem to set the DTE speed to a
certain value when answering.

