Here we can all chat about fixing the AT+ command structure and the associated responses.

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By Jens Jung
#88488 Hello everybody.

First something about me. I am new to µP programming. So far I have experience in BASIC (8052), Pascal (Delphi), and C # (VS).
I got a newly developed board with the said ESP8266 (WROOM02) and should now get it to work. I work with the STM32CubeIDE.
The UART to the WIFI module works, and I have been able to get everything working so far.
My command order:
AT -> OK
ATE0 -> OK
AT + CWMODE_CUR = 2 -> OK
AT + CWSAP_CUR = "MySSID", "MyPassword", 1,3,1,0 -> OK
AT + CIPAP_CUR = "192.168.1.1", "192.168.1.1", "255.255.255.0" -> OK
while (1) { (every 0.1 sec.)
AT + CWLIF -> 192.168.1.2 (PC is recognized when connected)
AT + CIPSTART = "UDP", "192.168.1.2", 5001,5001 -> CONNECTED (ALREADY CONNECTED)
-> + IPD (data string is received correctly)
AT + CIPSEND = 13 -> > -> VERSION = 001 \ r \ n -> SEND OK
}

But now the sent string is not recognized at the remote station (PC) or does not arrive.
On the other side my program (Delphi, UDP client) is running, which communicates with other hardware (same connection type and data strings) without any problems. I even extended the TimeOuts so I didn't miss anything.

When I watch the connection on the PC site with Wireshark, it shows always the ICMP message "port unreachable".
When I'm trying to establish a TCP connection, I didn't get any answer from the ESP.

Can any of you find any bugs in the configuration?

Thanks in advance.
Jens