Hi Steve
There are lots of devices that require Ethernet and an embedded web server can be achieved easily with 18k Flash and 10k of SRAM.
In production quantities cost is of importance and external devices add cost, weight, power consumption and size, making single-chip devices with Ethernet (and some with embedded PHY) popular.
The Freescale M52235, for example, has been very popular (with internal PHY) for about $5. 32k SRAM and 256k Flash is adequate for many industrial application - including MODBUS/TCP or Ethernet/IP where the stack fits along-side the application.
I have a simple AVR32 on-line at http://demo.uTasker.com which is running various applications including a TFT display that can be viewed on the web server - also FTP, TELNET and various other typical TCP services. It also supports IPv6 (global IPv6 [2001:470:26:105::99], although I think my provider's IPv6 tunnel is presently down). 80% of the Flash and 45% SRAM is still free for extensions. [I just checked - it has been up for 30 days and handled half a million frames since then]
A Kinetis K60 costs less that $5 and, together with a Micrel PHY, a crystal and RJ45 magnetics, allows a complete USB/Ethernet enabled device for under $10 and has ample room for many TCP/IP based applications and encrytion running happily together. Rarely does a full-blown application with USB and full TCP/IP support require much more than 120k of the 512k Flash space nor much more than about 32k of the 64k internal SRAM as in the cheapest parts.
When manufacturing say 10k units a year of such devices having full control of the stack (with Internet updates of TCP/IP protocols where needed) and lowest cost is very important. If you need to add say additional muticasting capabilities, VLAN or allow it to operate with multiple network addresses, or additional SNMP enterprise support to keep up with competitor's capabilities it can be done. If you are relying on a standard module to handle the stack you will have to pray that it does include it or that you can convince the manufacturer to build it in for you and somehow up-date the devices in the field.
Lantronix or Digi products (the uTasker TCP/IP stack is used in a similar one: http://www.xmodus.ch/sm_lan.html based on an ATMEL ARM7 with 32k SRAM) are popular for lab use where an extra $20 or $30 to hang on a ready-made stack is not an issue but once quantities go up the external module expense can be several times higher than the actual produts cost if were fully integrated. Usually it is rare to sell more than about 10..100 such devices to a customer since once quantities go up more an integrated TCP/IP stack makes more sense.
Regards
Mark
There are lots of devices that require Ethernet and an embedded web server can be achieved easily with 18k Flash and 10k of SRAM.
In production quantities cost is of importance and external devices add cost, weight, power consumption and size, making single-chip devices with Ethernet (and some with embedded PHY) popular.
The Freescale M52235, for example, has been very popular (with internal PHY) for about $5. 32k SRAM and 256k Flash is adequate for many industrial application - including MODBUS/TCP or Ethernet/IP where the stack fits along-side the application.
I have a simple AVR32 on-line at http://demo.uTasker.com which is running various applications including a TFT display that can be viewed on the web server - also FTP, TELNET and various other typical TCP services. It also supports IPv6 (global IPv6 [2001:470:26:105::99], although I think my provider's IPv6 tunnel is presently down). 80% of the Flash and 45% SRAM is still free for extensions. [I just checked - it has been up for 30 days and handled half a million frames since then]
A Kinetis K60 costs less that $5 and, together with a Micrel PHY, a crystal and RJ45 magnetics, allows a complete USB/Ethernet enabled device for under $10 and has ample room for many TCP/IP based applications and encrytion running happily together. Rarely does a full-blown application with USB and full TCP/IP support require much more than 120k of the 512k Flash space nor much more than about 32k of the 64k internal SRAM as in the cheapest parts.
When manufacturing say 10k units a year of such devices having full control of the stack (with Internet updates of TCP/IP protocols where needed) and lowest cost is very important. If you need to add say additional muticasting capabilities, VLAN or allow it to operate with multiple network addresses, or additional SNMP enterprise support to keep up with competitor's capabilities it can be done. If you are relying on a standard module to handle the stack you will have to pray that it does include it or that you can convince the manufacturer to build it in for you and somehow up-date the devices in the field.
Lantronix or Digi products (the uTasker TCP/IP stack is used in a similar one: http://www.xmodus.ch/sm_lan.html based on an ATMEL ARM7 with 32k SRAM) are popular for lab use where an extra $20 or $30 to hang on a ready-made stack is not an issue but once quantities go up the external module expense can be several times higher than the actual produts cost if were fully integrated. Usually it is rare to sell more than about 10..100 such devices to a customer since once quantities go up more an integrated TCP/IP stack makes more sense.
Regards
Mark
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