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undercon.gif (293 bytes)PicoWeb™ Frequently Asked Questions (FAQ)

So, who really has the World's Smallest Web Server?
Good question!  We believe that today it may be us, if you're talking about a full-function, stand-alone Web server with an Ethernet connection.  Our PicoWeb server PCB is smaller than a standard business card, and only has components on one single side.  We could make it substantially smaller, but that would drive up the assembly and parts costs.   It's a sure bet that we are going to see even smaller Web-enabled devices in the future.  It's our bet that we will be able to capture and keep the "low ground" in terms of cost with our unique, resource limiting networking algorithms.

Why do you call it a $25 Web server when it sells for much more than that?
The $25 amount originated as the total parts cost of the original PicoWeb "breadboard project" as described in our Circuit Cellar Online article.  Many people scattered around the world have built their own $25 PicoWeb "breadboard" using our schematic and firmware.  The $25 number also is an accurate bill-of-materials cost for moderate quantities of the PCB version of the PicoWeb server.  However, we are a for-profit operation, so what the public pays for PicoWeb servers manufactured by us is a bit more.

How can I use the PicoWeb Server to Web-enable an existing product?
If your product already has an RS-232 serial port which can be used to control/access the device, then the engineering effort required to make that device accessible via a Web browser can be minimal.

Can I do UDP and TCP with the PicoWeb™ Server?smallnew.gif (906 bytes)
Yes.  The PicoWeb server is not limited to use only by Web browsers.  The supplied PicoWeb firmware also supports custom programming using UDP and TCP.   With the latest release of the PicoWeb firmware (v2.xx), application code can initiate short outbound TCP/IP sessions with remote host computers by using special firmware routines.  Normally, the PicoWeb is restricted to servicing inbound TCP/IP sessions only.  UDP-based communication is also possible using the PicoWeb firmware.

Can I design and/or build my own hardware and still expect to make use of the PicoWeb™ server firmware?
Yes.  Lightner Engineering is actively seeking partners to develop products using the PicoWeb server technology.  We are equipped to do turn-key product design engineering, or we can leave the design engineering completely in your hands, using information we would supply.  Or, we can share the engineering duties...the choice is yours.  Our PicoWeb server product was created primarily as a development and engineering proof-of-concept tool.  Most likely the PicoWeb technology will need to be tightly integrated into your product to make it cost effective.  We are at your service to help make that happen.

Why doesn't the PicoWeb™ Server use a PIC microcontroller from Microchip?
We chose an Atmel microcontroller for the PicoWeb server primarily because of it's use of flash-based program and data memory.  This helps make firmware development quick and easy.  Nevertheless, the PicoWeb firmware could be ported to any of many other microcontrollers from a number of different vendors.  If you have a favorite one, Lightner Engineering would be happy to discuss such a project.

Is the PicoWeb™ server firmware available for license and how much does it cost?
Yes.  The firmware can be licensed for commercial use.  A single right-to-use license is included with the purchase of a PicoWeb server from Lightner Engineering.   A single right-to-use license for hardware of one's own construction may be purchased for under $10.  Please contact Lightner Engineering for quantity licensing information.

Where can I get the firmware source code for the PicoWeb server?
Sources for the "breadboard version" can be downloaded from the PicoWeb Web site.  This firmware can be used for non-commercial purposes at no cost under the terms of the license agreement.   Source code for the PCB version of the PicoWeb server is supplied as part of the PicoWeb firmware development environment which can be purchased from Lightner Engineering.   The use of this firmware for commercial purposes on hardware other than that supplied by Lightner Engineering is subject to a licensing agreement and fee.

Where can I get the development environment for the PicoWeb server?
A complete development version for the "breadboard version" can be downloaded from the PicoWeb Web site.  This firmware can only be used for non-commercial purposes under the terms of the license agreement.  Lightner Engineering also offers a complete firmware development environment for its PicoWeb server product line.

How can it get updates to my PicoWeb server development environment?
If you are an existing customer you can find what you need on our technical support Web page. 

Why is some of the PicoWeb™ server firmware source code in binary form?
Certain networking software algorithms used by the PicoWeb server are in a patent pending state.  Until such time that these patents are granted, the algorithms must be treated as proprietary information and cannot be disclosed in source code form without a strict non-disclosure agreement in place.  With the proper agreements in place, full PicoWeb server source code can be made available to third parties.

Where can I find latest copies of PicoWeb articles, white-papers, software, and errata information?
Please visit our downloads page.

Where can I buy the Atmel microcontroller for the PicoWeb server "breadboard project"?
You can buy Atmel 8515 microcontroller parts in small quantities from the AVR Forum or from Iguana Labs.  (For all the other parts you may need, we suggest you take a look at Digi-Key.)

Where can I find information about assembly language programming of the PicoWeb server?
The Atmel Web site has a document titled 8-Bit AVR Microcontroller with 4K/8K bytes In-System Programmable Flashwhich describes the AT90S8515 microcontroller, including information on programming it in its AVR assembly language.

Where can I find information about PicoWeb firmware/Web page development?
Our Web site's downloads page has a PDF document titled How to Build a PicoWeb Project which describes the steps required to create Web pages and/or firmware for download into the PicoWeb server. 

Where can I find information about programming of the PicoWeb server using "pcode"?
Our Web site's downloads page has a PDF document titledPicoWeb Pcode Interpreter which describes PicoWeb pcode.

Do you accept payment via credit cards?
credit_MC_visa.gif (2104 bytes)We accept both domestic and international orders via credit card (Visa, MasterCard, AMerican Express and Discover). Details can be found on our ordering information page.

Suddenly I can no longer download new firmware into my PicoWeb Server.  What's wrong?
We have had reports from the field of the Atmel microcontroller occasionally entering a "confused" state when a PicoWeb Server is power-cycled with the programming cable attached to a PC. Once in this state the Atmel microcontroller will repeatedly fail to download new firmware. To correct this problem, unplug all of the cables from the PicoWeb server, wait a few seconds, re-apply DC power to the PicoWeb Server, then re-attach the other cables. The source of this problem appears to be "leakage" current, supplied to the PicoWeb via the cables attached to the PC, preventing a "clean" power-up sequence, as required by the Atmel flash programming circuitry.

I can't seem to use Javascript in my PicoWeb Web pages?
PicoWeb firmware releases prior to 12/2/99 had a problem with the interpretation of { }'s in any HTML pages downloaded to the PicoWeb server.  This problem has been fixed.  Please contact Lightner Engineering at lightner@lightner.net for an updated version of the PicoWeb firmware source code file "lib\url.asm".  

When I'm building PicoWeb projects something is accessing the floppy drive?
You are probably using McAfee's virus protection program with the older version of the PicoWeb development system (i.e., version before v2.00).  For reasons we don't understand this causes drive A: to be accessed each time Atmel's AVR assembler (AVRASM.EXE) is run.  Either turn off the virus protection program's "file check when Run, Create, Rename etc..."  feature under "system analysis", or make sure a formatted floppy disk is in drive A:.

I sometimes see random corruption of the microcontroller's EEPROM bytes?
Certain PicoWeb servers built prior to hardware revision level v4.1 are subject to infrequent random corruption of the Atmel processor’s on-chip EEPROM during PicoWeb power-cycling. This is the result of a power "brown-out" problem descovered by Atmel and documented in one of it's errata sheets on the Atmel AT90S8515 microcontroller.   Because the PicoWeb’s Ethernet address and IP addresses are usually stored in on-chip EEPROM, the symptom of this EEPROM corruption event typically is an inability to contact the PicoWeb server over the Ethernet until the PicoWebg firmware is downloaded again. Newer PicoWeb servers (v4.1 and later)  include a “reset controller” chip which holds the Atmel microcontroller in reset during these power “brown-out” conditions.

Do you support development/download under Windows NT and Windows 2000?smallnew.gif (906 bytes)
Yes.  However, you may need special user privileges (typically reserved for "Adminstrators") in order to make use of the PC parallel port under Windows NT and/or Windows 2000.

Do you support development/download under Linux?smallnew.gif (906 bytes)
No.  Today we only support firmware development and download under Microsoft WIndows.   However, we expect this to change in the future.  We have just switched our development tools over the "public domain" GNU software tools, including the GNU AVR assembler, linker and AVR C-compiler (gcc).  The GNU tools also run on Linux, althogh a bit of work is needed to port our other software to Linux.  One of the biggest problems with these operating systems is our need to access the PC parallel port for the purposes of downloading firmware into the PicoWeb's microcontroller.   Special drivers for Linux are one way to solve this problem.   However, do have a "hardware fix" working in our lab.  With a special cable, one PicoWeb server can be used to download a second PicoWeb server over the Ethernet.  This option does not make use of a PC parallel port.  Please stand by for announcements regarding this new option. 

Can I program the PicoWeb™ Server using C?
Yes.   The new GNU-based PicoWeb development system (v2.xx) is compatible with a version of the GNU C-compiler which targets AVR machine code (in program memory).   However, because there is a limited amount of unused program memory in a PicoWeb server (i.e., ~2K bytes), only a limited amount of application code can be written in C.   Complex PicoWeb applications will have to continue to rely on PicoWeb pcode in order to be able to execute out of the much larger 32 Kbyte "code space" offered by the PicoWeb's serial EEPROM chip. 

Can I send e-mail with the PicoWeb™ Server?
Yes.  The latest release of the PicoWeb firmware (v2.xx) allows application code to initiate short outbound TCP/IP sessions with remote host computers.  One of the sample PicoWeb projects shows how to send a short e-mail message to an SMTP mail server using this feature.

Why do firmware downloads fail with parallel ports on certain PCs?
If when attempting to download firmware into a PicoWeb server you get repeated errors of the form "Chip can not be enabled" then you need to check your PC's parallel port.  Verify that the parallel port is "enabled", that it is properly configured, and that it is not being used (and/or shared) by another program.  On some PC's, the parallel port must be taken out of "bi-directional mode" (sometimes called ECP or EPP mode) and placed in "compatibility" mode.  Note also that certain programs and/or Windows drivers can interfere with the PicoWeb programmer.  Iomega Zip drives and external CD-ROM drives which use the PC parallel port have been known to cause problems of this kind.  One way to quickly "disable" any such installed drivers is to press the F8 function key during Windows 9x boot and then select "safe mode". 

Why does the PicoWeb project "build" process hang-up my PC?smallnew.gif (906 bytes)
Certain versions of Norton Anti-Virus 2000 are known to cause the PC to hang-up (or sometimes abort the GNU assembler) during PicoWeb project builds (i.e., "pwbuild").  This happens repeatedly when the GNU assembler (avr-as.exe) runs, a "plain-vanilla", console-mode, 32-bit Windows C-program.  This is clearly a bug in the anti-virus software.  On some PC's this error requires the PC to be re-booted.  The work-around we recommend is to disable anti-virus "auto-protect" when running PicoWeb project builds.  (Also, we suggest that you report this bug to Symantec!)


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Last modified: March 05, 2001