
Introduction
few years ag MCS Electr nics intr duced Easy-TCP/IP, which gave y u a
way f interfacing AVR micr c ntr llers t the Internet in a fast, c st
effective way. Easy-TCP/IP is n w being used in the w rld f embedded
electr nics.
We are n w intr ducing the Easy-TCP/IP TWI – a TCP/IP interface, which uses nly
a few I/O pins f y ur micr c ntr ller,and requires minimal change in y ur
riginal pr gram c de. Easy-TCP/IP TWI was devel ped in resp nse t ur users’
feedback.
The key advantage f the Easy-TCP/IP TWI is that it nly uses f ur micr pr cess r
pins, i.e., tw I/O pins f r I²C serial c mmunicati ns, and ne interrupt pin and a
reset pin. Thus only 4 I/O pins are needed t implement a full TCP/IP interface.
The previ usly released TCP/IP b ard used ab ut 16 I/O lines, making it nly
suitable f r relatively large AVR c ntr llers. If y u are upgrading an applicati n t
TCP/IP, y u are much m re likely t have 4 I/O pins available than 16. And y u
d n t need much m re r m f r the changes needed in the pr gram c de.
The reducti n f I/O pins f the Easy-TCP/IP TWI makes it sl wer than the EASY-
TCP, but f r a l t f embedded applicati ns high speed is n t a requirement. It’s up
t y u t decide whether y u ch se speed, Easy-TCP r a c mpact and ec n mic
Easy-TCP/IP TWI. Using fewer pins requires that reading and writing be serial
rather than parallel, which makes the TWI interface sl wer than the parallel interface.
This guide will help y u implement Easy-TCP/IP TWI. It assumes y u have s me
experience with the Easy-TCP/IP b ard. If y u have n t, please als read the East-
TCP/IP manual, available fr m www.mcselec.c m. The exact l cati n is :
http://www.mcselec.c m/index.php? pti n=c m_d cman&task=d c_d wnl ad&gid
=97&Itemid=54
N te that Easy TCP/IP-TWI requires the 7010A-Adapter B ard.
The Easy TCP/IP M therb ard is nly intended t test this 7010A-Adapter B ard.
Y u can als use an NM7010A m dule r the W3100A chip in y ur design.