Resolving AT+CIPSTART command response "STATE: IP PROCESSING"

Question

Usually this command response is CONNECT OK, but some time it gives following response.

AT+CIPSTART="TCP","api.thingspeak.com",80
STATE:IP PROCESSING

CONNECT FAIL

and status command shows:

AT+CIPSTATUS?
+CIPSTATUS:
STATE:IP PROCESSING 

OK

How can I get away with this status of IP PROCESSING? I have tried AT+CIPCLOSE and AT+CIPSHUT, but could not solve the problem and I have to reset the GPRS/GSM module. Regards,

Answer 1

According to SIM900_TCPIP_Application Note_V1.02 the IP PROCESSING state is used only when working with GPRS multi-connection: AT+CIPMUX=1 So it's probable that you might have a problem with your multiple connections.

If you don't need to support multiple connections at the same time you can simply use GPRS single connection: AT+CIPMUX=0 this may solve your problem.