HPLX.NET FAQs: Networking FAQ


The 200LX Networking FAQ

Section 1.
Networking fundamentals: what is all this, anyway?
Section 2.
Hardware: what do I need to buy?
Section 3.
Software: what can you do with it?
Section 4.
Troubleshooting



SECTION 1.

1.1. What is networking?

In this document, the term "network" will refer to a connection between
two computers, the 200LX and a "desktop" computer. This is an
"Ethernet" connection. It resembles a direct connection via a serial or
parallel port (something you might accomplish with LapLink) except
that it requires a special adapter board, has different cabling, and is much
faster.

1.2. What does the term "Ethernet" mean?

It refers to the physical way the network is wired, as well as the
protocols used to transmit data over those wires. Other network types
include "ARCnet" or "Token Ring." Most
networks nowadays use the Ethernet standard, and use the 10BASET
(ten-base-tee) wiring scheme. In this scheme, twisted-pair wiring is run
from each computer on the network to a central hub, which links all of
the computers together. "Twisted pair" cabling is similar to telephone
wire, but with eight wires instead of four. (The wires are grouped into
four pairs, and each pair consists of two wires twisted around each other
-- hence the name "twisted pair.") Each end of a twisted pair cable has an
RJ-45 connector on it, which looks like a larger version of a telephone
cord plug.

1.3. So what good is Ethernet on the 200LX, anyway?

Perhaps most important, you can run backups. This is not as important
for palmtops with small internal RAM drives, because the software
needed to run effective backups will take up proportionally more room,
and besides, a small flash card will do the job nicely and be more
portable and probably less expensive. If you have NO money, you can
still do a serial port backup to your hard drive in a relatively short
amount of time. However, for larger palmtop RAM drives, such as
32MB, the backup problem becomes critical. A flash card big enough to
hold all of the data on your RAM drive is fairly expensive, and who
wants to waste 32MB of flash card? Serial port backups are way too
slow for a full 32MB backup. This is where the Ethernet card shines. It
is relatively inexpensive compared to a flash card, and yet allows high-
speed backups.

But backups are only one of the many applications of palmtop Ethernet!
What you can do depends largely on what software you can run, and is
covered more fully in section 3. For now, suffice it to say that you can
run remote applications, print to other printers, communicate via e-mail,
run network diagnostics, and... well, pretty much any reason you'd wish
to be connected to another computer in the first place!

1.4. What are the advantages/disadvantages of Ethernet over using a
modem in the 200LX?

The advantages of using an Ethernet connection over a modem
connection are that it is much faster (on the order of twenty times as
fast), it takes up less power than a modem. The
disadvantages are that you need special hardware; you cannot make an
Ethernet connection over a regular phone line.

Additionally, the distance between you and the computer you are
communicating with must be fairly short-- a few hundred feet at most.
(Unless, of course, your remote computer is hooked up to another
network with a longer range, such as the Internet, and can redirect you.
In that manner, you can go around the world via Ethernet. However,
direct computer-to- computer connections are fairly limited in distance.)
All things considered, comparing a modem connection with an Ethernet
connection is like comparing apples and oranges. Each has its own use.

1.5. What are the advantages/disadvantages of Ethernet over using a
direct serial or parallel cable connection in the 200LX?

Serial connections are often used with programs like LapLink to transfer
files from desktop to palmtop, or vice-versa. It's a simple matter to buy
a cable and set up some file transfer software so you can copy things to
and from your 200LX.

Most every desktop PC has a serial port you can hook up your cable to,
so the serial connection is probably the most common. The
disadvantage here is that it's the slowest type of connection; the best you
can do is 115,000 bps, which translates to roughly 10K per second (and
that's if you're extremely lucky).

Parallel connections on the palmtop are much rarer, because the 200LX
has no parallel port built in. There are at least two parallel port cards
that work in the 200LX, the better of which seems to the be Transdigital
card. With one of these, it is possible to connect (via LapLink or
InterSvr or other connection software) and do transfers at speeds from
2-5 times faster than a serial connection. Not bad at all, but still not as
fast as we'd like.

Ethernet connections are the fastest of the bunch, with a theoretical
maximum of 10Mbps (bits per second, not bytes), or roughly eighty
times faster than a serial connection, and seventeen times faster than a
parallel connection. Real conditions will yield less speed than this, but it
is still extremely fast. On the palmtop, measured speed is around 100KB
(bytes, not bits) per second, or about 8% of the theoretical maximum.
This is probably mostly due to the palmtop's limited processing power,
because although even Pentium II computers never seem to achieve
10Mbps, they come a lot closer than the 200LX.

Even so, it is obvious that a palmtop with an Ethernet connection is
capable of transferring data at a very high rate of speed!


Section 2. HARDWARE

2.1. What sort of Ethernet hardware will work in the palmtop?

The most obvious requirement for an Ethernet adapter that will work in
the palmtop is that it be a PCMCIA card. Second, it must not draw more
power than the palmtop can supply, or
roughly 150 milliamps. Finally, it must have drivers that allow it to
work with the palmtop's non-standard PCMCIA hardware.

Unfortunately, this eliminates the vast majority of PCMCIA Ethernet
adapters. Although many of them meet the power requirements, there
are almost none that have drivers that allow them to work with the
200LX.

The only two types of Ethernet card that work with the 200LX are the
Silicom Ethernet Card (www.silicom.co.il) and the Accton
(www.accton.com) EN2212/6 cards.

The Silicom card was specifically designed with drivers from the
company to work in the HP DOS palmtops. It ships with all necessary
drivers and documentation to allow you to use packet-driver applications
(more on this later) or log in to a NetWare server. The card itself has a
female jack on it, and a proprietary twisted-pair cable with an RJ-45
connector on the end of it comes with the card. This allows you to plug
directly into a wall jack; perhaps not the most elegant of solutions, since
the cable is not very long and, if damaged, the user must buy a new one
from Silicom. (There have been at least two reported cases of the
Silicom cable being defective and needing to be exchanged.) The other
disadvantage of the Silicom card is that the drivers do not work with a
double-speed palmtop; the memory on the card reports as damaged in
the double-speed unit. Silicom has no plans to fix this problem.

The Accton EN2212 and EN2216 cards were not factory designed with
the 200LX in mind. However, there are drivers available on SUPER
(www.palmtop.net) called LXETHER3 which allow use of this card in
the palmtop. The EN2216-1 is the recommended model for palmtop
usage. The card itself has a female jack on it, where a proprietary
breakout box plugs in. This box has a female RJ-45 jack on it, so you
can plug your own twisted-pair cable into it. This breakout box is much
shorter and more durable than the Silicom cable, and provides the
advantage of having LEDs for connection and data movement. Also, the
drivers for the Accton cards work on both single- and double-speed
palmtops. The disadvantage of the Accton card is that it only includes
support for packet- driver applications. Other functions, such as logging
in to a NetWare server, must run over the packet driver if desired,
leading to greater complexity.

It is worth noting that there are numerous cards (such as some made by
USLogic, a brand sold by Computer City) which are identical to the
Accton cards and which will work with the drivers on the SUPER site.

2.2. How much will these cards cost me?

The Silicom card can be had for between $100-$150, depending on
where you find it. A reliable source is Precision Guesswork
(www.guesswork.com). The Accton cards can be found many places.
Try Internet Shopping Network (www.isn.com), or CompUSA Online
(www.compusa.com). The EN2216-1 is the one you want; it should be
around $70.

2.3. What is the difference between the EN2216-1 and the EN2216-2?

The cards themselves are identical, but the breakout boxes are different.
The EN2216-1 includes just an RJ-45 jack, while the EN2216-2 includes
both an RJ-45 jack and a coaxial cable
connector. The -2 model is therefore larger in size, weight, and probably
current usage. For the palmtop, you can't use a coaxial cable network
anyway; it draws too much current. Hence, stick with the 2216-1.

2.4. What hardware will I need to connect to another computer?

The computer you want to connect to must either be on a LAN and have
an Ethernet connection to a hub, or at least an Ethernet card installed. If
you are only going to be connecting your 200LX to your
otherwise-isolated computer, you will probably not have an Ethernet
card installed and will need to buy and install one. Something like the a
Dlink SN2000 (for ISA bus) or 530-TX (for PCI bus) would be a good,
low-cost solution. These cards generally run from $30-$50 and can be
found at almost any computer store.

If you are trying to connect to a computer that's already on a LAN, such
as a work computer, you will need an RJ-45 jack that hooks into the
LAN. From there, you can access the
other computer. If you have a spare data jack near your desktop, that's
good. If not, you can buy a cheap hub (which is kind of a "splitter" to
join several different cables) and plug your network connection into the
"uplink" port. Then run two more twisted-pair cables, one to your
desktop and one for the palmtop. Presto! You now have a connection
for your palmtop, and your desktop is still connected.



Section 3. SOFTWARE

3.1. Okay, what software can I run now that I have my hardware
installed?

First, let's cover some basics. To run ANYTHING, you need to be able
to see the Ethernet card in the palmtop. Unfortunately, the drivers for
most cards won't see them in the palmtop, because the 200LX does not
use a standard Intel PCIC compatible controller for its socket.

Enter the enablers. Both the Silicom and Accton cards need to have
enablers run before you can do anything with them. Basically, these
enabler programs allow other applications to see the card and talk to it--
much like CIC100 allows programs to see and talk to modems.

The enabler for the Silicom card is called SEHP.EXE. You put the
Silicom card in the socket and run SEHP and it enables the card. After
that, you can run the packet driver, or the NetWare ODI driver.

The enabler for the Accton card is OP2216.EXE. It works the same as
the Silicom enabler; place the card in the socket and run OP2216.

These enablers are not TSR's like CIC100 is; there is no resident code,
so they take up no memory. They merely configure the card and the
palmtop and then exit.

One consequence of running the enablers is that you cannot thereafter
place other cards in the socket without turning off the machine, or
rebooting.

3.2. Okay, so after I run the enabler, what then?

Then you can run the actual drivers for the card, whatever they may be.
Probably the most common driver type is a packet driver. A packet
driver is a TSR that will transfer data to and from the card. Other driver
types include ODI drivers (for logging in to a NetWare server) or NDIS
drivers (for use with MS LanMan and other SMB clients). There are
many others
that I won't get into because, frankly, it's getting late.

These drivers must be specifically designed for the palmtop! Just
because you've run the enabler, don't think you can just run any driver
and have it work. It must be specifically tuned for the palmtop. The
Silicom card comes with a compatible packet driver and an ODI driver.
The Accton card has a packet driver only.

3.3. Okay, so what does THAT let me do?

A lot. The ODI driver will allow you to log in to a NetWare server,
which is extremely useful-- but only if you have a NetWare server to log
in to. In this day of Windows NT, those are becoming more and more
rare. Still, if you do have a NetWare server, you then have access to the
server's drive and can do backups, run other programs, etc. Very useful.

The packet driver, however, is even better. There are ton of applications
that can run over a packet driver, including telnet clients, FTP clients,
web browsing applications, e-mail
programs, etc. Of course, you must consider their system requirements;
a 32-bit graphical web browser won't run on the palmtop. Best of all
would be a SysMan compliant program. One example of this is PNR. It
is designed for a modem and PPP, but can be run over an Ethernet
packet driver instead of a PPP packet driver. In this way, you can get
full SysMan
compliance and the super-speed of Ethernet.

Other applications that run over a packet driver include:

- LanWatch, sold by Precision Guesswork. A network analyzer; turns
your 200LX into a fantastic network diagnostic tool.

- NFS clients. If you have a Unix machine on your network, or are
running NFS on your NetWare, or have an NFS server on your WinNT
or 95 desktop, you can mount drives on your
200LX and do backups.

- Printer clients. With the right server running, these can be mounted by
NFS software, and allow you to print to remote printers.

- Windows 95/98 network clients. With these, you can login to your
Win95/98 drives and printers.

- NetWare login clients. Although the Accton cards do not come with an
ODI client, you can still log in to a NetWare server by running PDIPX
from Intel.

- FTP, Telnet, ping, IRC, and other TCP/IP clients and servers.

3.4. Okay, okay, I get the picture. Are there any palmtop- specific
programs in the works that take advantage of Ethernet?

There is a rumor of a project to make WWW/LX Plus support Ethernet
as well as modem connectivity. This would greatly speed up
downloading e-mail off of local POP3 servers, as well as increase web
browsing speed.


Section 4. TROUBLESHOOTING

4.1. Help! I installed a network card in the palmtop, and in the desktop,
and ran a cable between them, but they don't see each other! The
connection light is not even on!

For a direct connection (i.e. without a hub) between two computers, you
need to use a special "crossover" cable. This is analogous to the
"null-modem" serial cable that programs like LapLink need to establish
a serial connection. The theory is that you must connect the transmit pin
of one side to the receive pin of the other, and the receive pin to the
transmit pin, to get communication.

You can buy these crossover cables, or make one yourself if you have
RJ-45 ends (available at Radio Shack and most electronics stores) and a
crimper. You must cross over the following wires:

RJ45 pin to RJ45 pin
-------- --------
1 3
2 6
3 1
6 2

Pin 1 would be the first one on the left when looking at the RJ- 45
connector from the bottom.



END OF FAQ

(c) 1998 David Sargeant
All rights reserved.


Copyright 1999, David Sargeant.
Last Updated 1-2-1999
Webmaster

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