Research & Development
Page 7of 7
Revision 1.3
2002/7 From 3JTech
iChip Description
iChip is a low-cost intelligent peripheral device, which provides Internet
connectivity solutions to a myriad of embedded devices. A serial bus interfaces iChip
to a device’s host processor, via an on-chip UART. An optional 8/16-bit interface to a
host processor is supported as well, by adding an external UART for low-bandwidth
applications or a dual-port-RAM for high bandwidth applications. iChip also directly
interfaces a serial or parallel data modem, through which it supports independent
communications on the Internet via a dial-up ISP connection. An optional Ethernet
connection is supported by adding an external, 16-bit MAC.
As an embedded, self-contained Internet engine, iChip acts as mediator device
between a host processor and an Internet communications platform. By completely
offloading Internet connectivity and standard protocols, it relieves the host from the
burden of handling Internet communications. From the perspective of a host device,
the complexity of establishing and maintaining Internet-related sessions are reduced
to simple, straightforward commands, which are entirely dealt with within iChip’s
domain. Through its host Application Program Interface, iChip accepts commands
formatted in “AT+i ”extension to the renowned Hayes AT command set.
Commands are available to store and manipulate functional and Internet-related
nonvolatile parameter data; transmit and receive textual Email messages; transmit and
receive binary (MIME encoded)Email messages, fetch HTML web pages; and
download parameter and firmware updates for the host device or iChip itself. Send
command variants exist for immediate communications or scheduled
"store-and-forward ”.
iChip supports several levels of status reporting to the host. In addition, the iChip
is connected to a modem device, the host may issue standard AT commands to gain
direct access to the modem. In the presence of AT commands, iChip automatically
operates in transparent mode, thus emulating a direct host to modem environment.
Using the attached communications platform, iChip gains access to the Internet
to independently manage standard Internet protocols that transmit and receive
messages. When hooked up to a standard data modem device, iChip provides all the
necessary procedures to dial-up an ISP, authenticate the user and establish a PPP
connection.
