more on postage-stamp KnowNow microservers

[Eugene Leitl <eugene.leitl@xxxxxxxxxxxxxxxxxxx>]

(((full text of the article included. Notice on how many protocol
   functionality they were able to fit into a 5 kByte footprint.
   Also notice the "if-all-you-have-is-a-hammer" mindedness of the
   Linux bigot)))

http://dailynews.yahoo.com/htx/zd/20000914/tc/world_s_tiniest_and_cheapest_web_server__1.html

Thursday September 14 11:16 AM EDT
World's tiniest (and cheapest!) Web server? 

By Rick Lehrbaum, Linux

At about one square inch, and $30, NetMedia's SitePlayer is a real
Ethernet Web server.

NetMedia has announced "the world's smallest Ethernet webserver." It's
implemented as a tiny 1.1" x 0.9" PC board, and only requires the
addition of +5V DC power and an Ethernet connector to function as a
standalone webserver. Now, get this: the tiny plug-and-play webserver
will be priced at just $39 for a single unit, $30 each for 100, $20
for 100,000 -- and, it's just $12 each, if you happen to need a
million of them!

Even at $39, if it's really a functioning webserver, there must be a
catch. Right? Well, sort of yes -- but sort of no. Let's delve a level
deeper into the details.

For starters, here's what the tiny device, called the SitePlayer,
looks like:

Looking at the above pictures, you'll notice that the SitePlayer
contains just four substantial components: two integrated circuits, an
oscillator crystal, and a connector. The two chips are a Philips
integrated 8051-based microprocessor and a Realtek Ethernet
controller.

That can't run Linux, can it?

If that was the first thought that crossed your mind, you were
absolutely right. In order to achieve both its miniscule size and
miniscule price tag, the SitePlayer is extremely stingy in its use of
resources. So stingy, in fact, that it doesn't contain a conventional
operating system at all. Instead, NetMedia created a small system
control program that fits within just 5K bytes of memory, which
supports the device's internal functions and implements the supported
Internet protocols (which currently include ARP, ICMP, BOOTP, UDP,
TCP/IP, and HTTP).

As you might have noticed, this little gem is a classic example of
another well-known four-letter engineering protocol: KISS (for "Keep
it simple, stupid!").

What's it made of?

From a hardware perspective, the heart of the tiny SitePlayer is a new
Philips spin on an old Intel theme -- the latest Philips 8051
variant. That processor (a P89C51RD2) includes 64KB of built-in
nonvolatile Flash storage memory, plus 1KB of built-in static RAM
memory.  There's also a built-in serial port and some digital I/O. (A
pdf datasheet on the Philips P89C51RD2 is available here). According
Jack Schoof, NetMedia's founder and CEO, the P89C51RD2 is so new that
there are not more than fifteen of them in the US, right now.  (That's
probably why he wouldn't lend me his prototype SitePlayer to play
with!)

All of the SitePlayer's interface connections are via a single 11-pin
connector (visible in the picture, above). The signals on those pins
are: Ethernet Tx+, Ethernet Tx-, Ethernet Rx+, Ethernet Rx-, serial
TxD, serial RxD, Ethernet Link status LED, +5VDC power, and ground.
There's also a 2-pin utility connector which carries a pair of
signals, which can be asserted to reset the system or to restore
factory default settings in case the system gets into an unrecoverable
state.

You may have noticed that there's no onboard RJ45 Ethernet
connector. NetMedia left off that connector because adding it to the
tiny module would have nearly doubled its size, and because they
believe most users of the SitePlayer will want to provide their own
RJ45 connectors on an outside edge of their products'
enclosure. NetMedia also omitted the Ethernet interface magnetics,
because it has become easy to obtain inexpensive RJ45 connectors with
built-in magnetics (see this pdf datasheet).

For customers wanting to use the SitePlayer without rolling their own
companion board, or for evaluation purposes, NetMedia sells an
optional RJ45 adapter board that forms a tiny stack with the SitePlayer.
See the two threaded mounting holes that are located to the left and
right of the RJ45 connector? These are for mounting the two-module
sandwich inside an enclosure.

How does it work?

The SitePlayer was designed to be extremely easy to use. According to
Schoof, all you need to do is hook it up to a source of power, plug it
into the 'net via its Ethernet connection, and begin feeding it data
over its two interfaces (Ethernet for web connection; serial port for
local host connection). Assuming you follow the unique but supposedly
simple protocols, your data will magically show up on the web!

How does the SitePlayer actually operate? Here's a description of how
the device works, taken from NetMedia's press release announcing the
SitePlayer:

SitePlayer contains a powerful object system called SiteObjects which
allow graphical images, text, music, links, radio buttons, or
checkboxes to change based on live data from the device processor
without the need for CGI scripts or Java programming. A web page can
contain a graphical knob rotated to a position, a switch can be
toggled up or down, or a link can change based on a variable in the
device processor.

Standard web authoring tools are used to make the pages for
SitePlayer. Web pages are downloaded to SitePlayer's flash memory over
the Internet. SitePlayer firmware updates are also downloadable,
keeping SitePlayer current. A library of graphical knobs, switches,
LEDs, and other user interface tools are provided for web page
development.

SitePlayer is, basically, a "dumbed-down" webserver. You simply use
its predefined commands and protocols to feed it web pages from one
side (Ethernet/web), and data "objects" from the other side
(serial/local-host). The device does the rest.

Schoof has a written a detailed whitepaper entitled "Web Enabling Your
Products Without Writing Any TCP/IP Code", which describes the
SitePlayer's unique architecture and command protocols. It's available
online, here.

What's it good for?

By now, you've certainly figured out that you're not going to be
hosting a "normal" website on a SitePlayer. Not with 64KB of Flash
storage and 1KB of system memory! Compare that with the dozens of
gigabytes of disk storage and hundreds of megabytes of system memory
of "normal" webservers.

SitePlayer has a different role in life. As Schoof puts it, he created
SitePlayer "to serve in applications like audio equipment, appliances,
thermostats, home automation, process control, test equipment, medical
devices, vehicles, machine control, and remote monitoring."

Note that there are few instances where the SitePlayer is a complete
embedded systems.  Instead, it's meant to be used as an auxiliary
subsystem solely focused at serving predefined web pages. It's a
"website coprocessor," which is added to a system that contains some
other form of control processor. Accordingly, SitePlayer was designed
to be easy to be added to existing systems, to web-enable them, or to
be incorporated into new embedded system designs, as a means to
offload simple webserver functions from the system's main control
processor.

Think of the SitePlayer as a virtual instrument panel. You send it
data "objects" over its serial port (at up to a megabit per second),
and it converts that data into displayed "objects" that appear on its
internal HTML pages. "SitePlayer eliminates expensive physical
interfaces such as LCDs, knobs, and switches, thus paying for itself,"
claims Schoof. By eliminating those user interface components, it also
tends to reduce the system's size and power requirements, resulting in
further cost savings.

Incidentally, NetMedia is developing a "high end" SitePlayer, with a
slot for Flash memory cards of up to 64 MB capacity. Schoof says he
expects that model to compete with traditional servers in many
applications, and that NetMedia will offer it in a consumer-oriented
version for creating "unhackable home websites." Its target retail
price? $149, including an 8MB Flash card.

Where did it come from?

NetMedia was founded in 1993 by Jack Schoof, who is currently the
company's CEO. Schoof had previously founded a company called
Artisoft, which was one of the first companies to popularize low cost
peer-to-peer networking through its LANtastic networking product, at a
time when LANs were still too expensive to be commonplace. Artisoft
was instrumental in bringing down the cost of networking -- including
both hardware AND software -- to a level where it could begin to be
ubiquitous in small business environments.

Starting in 1993, Schoof's new company (NetMedia) began developing
products and technologies for the home automation market. One such
invention was a unique video camera that transmit its images over
short ranges using low-level TV-band RF signals, allowing them to be
received on an ordinary TV. Another product was the BasicX, which
Schoof describes as "a Basic Stamp Killer". The Basic Stamp is a tiny,
inexpensive, and very easy-to-use microcontroller board that has
become a tremendous hit among students, experimenters, hobbyists, and
has also found a home in some commercial projects.

From these products came seeds of the SitePlayer. Schoof attributes
the SitePlayer idea to requests from his customers, who were looking
for a tiny Internet access device, similar in size to the BasicX, but
with just two simple connections (besides power) -- an Ethernet port,
to connect to the 'net, and a serial port, to receive data from the
system needing webserver services. Only primitive webserver functions
were required, in order to implement simple remote data acquisition
and control.

And the verdict is . . .

After meeting Schoof, eyeballing his (non-operating) SitePlayer, and
learning about how it's supposed to work, I must say that I'm highly
impressed with both the tiny device and the man behind it. If it works
as claimed, and if NetMedia can actually sell SitePlayer profitably in
the $25-35 price range, I expect it to be quite successful.

Overall, I'd say the most significant aspect of SitePlayer is its
elegantly simple design, looked at from many perspectives -- including
hardware, software, and overall ease-of-use.

Which leads to the question: Why not develop a SitePlayer-like device
based on one of the latest highly integrated ARM core based
system-on-chip ICs -- with an open architecture, and supported by
embedded Linux and open source software? Why not create a universal
web-node micro-platform that the growing masses of open source
developers can tinker with, add to, and find clever uses for? The day
is not far off when billions of networked nodes will be "wired"
together on a single extended 'net. The sooner we pool our collective
wisdom to create the required solutions, the sooner we'll really get
there.

Maybe an ARM-and-embedded-Linux based SitePlayer will be NetMedia's
next product?  Thanks to Moore's Law, the size and cost of doing it
are bound to be affordable sooner than you'd expect!