ESP8266 Community Forum

I am new about ESP8266 module.
i try connect baidu web site with client.
So i using AT+CIPSTART=4,"TCP","220.181.111.85","80"
i received message with "ERROR unlink" from module.
But i use AT+CIPSTART=4,"UDP","220.181.111.85","80"
It is OK... Why can't connect with TCP?
Please let me know reason about above problem.

Thank you.

you receive error unlink on TCP because your syntax is not correct. port shouldnt be inside " ".
and you receive OK on UDP because udp is stupid. it doesnt really know if it is connected or not. it just reply you with ok even with a wrong syntax or a wrong url.

that resolved the same issue for me, thanks villTech!

villTech wrote:you receive error unlink on TCP because your syntax is not correct. port shouldnt be inside " ".
and you receive OK on UDP because udp is stupid. it doesnt really know if it is connected or not. it just reply you with ok even with a wrong syntax or a wrong url.

Thx friend.. looks like documentation has some wrong information. Now i got my client working