The Qws Embedded Web Server
The Qws embedded web server consists of a PIC16F877 microcontroller connected to a standard ISA Ethernet interface card. The total cost of the project was approximately six pounds (about ten US dollars), thanks largely to the kind donation of the Ethernet card.
The microcontroller offers 14 kbytes of FLASH program memory (organised as 8192 14-bit words) and 368 bytes of data RAM. The server code occupies about 1800 words of the program memory, the remainder being used as a filing system to store the web pages to be served. Approximately 270 bytes of data RAM are used.
The processor clock runs at 20 MHz, giving an instruction rate of 5 MHz.
The server supports the address resolution protocol (ARP) and ‘ping’, and, of course, the hypertext transfer protocol (HTTP). Unlike many embedded web servers, however, the implementation is ‘stateful’: it can service requests on up to six separate connections simultaneously.
The prototype server sometimes hosts the www.quinapalus.co.uk website. Note that this is for demonstration purposes only, and the site may be unavailable for extended periods while development work is being carried out.
If you’d like to know more about this project, please e-mail me.
This page most recently updated Thu 26 Jul 08:28:25 BST 2018
New: Free, fast, and accurate ARM Cortex-M3 floating-point library; UnLife; Pound Shop BASIC; Logic Tutor
Qxw is a free (GPL) crossword construction program. Answer treatments, circular and hex grids, jumbled entries, more besides. Release 20140331 for both Linux and Windows. More...
My book, ‘Practical Signal Processing’, is published by Cambridge University Press. You can order it directly from them, or via amazon.co.uk or amazon.com. Paperback edition now also available. Browse before you buy at Google Books. Wydanie polskie.
If you find this site useful or diverting, please consider a donation to NASS (a UK registered charity), to KickAS (in the US), or to a similar body in your own country.
All trademarks used are hereby acknowledged.