SIM900 GPRS: Consecutive AT+CIPSEND

Question

I'm having some trouble being able to consecutively use AT+CIPSEND with the SeeedStudio SIM900 GPRS module on Arduino. This is my sequence of AT Commands (using SSCOM3.2):

AT+CIPSTART="TCP","xx.xx.xx.xxx","80"

OK

CONNECT OK
AT+CIPSEND
> PUT /?data="datasequence"
(CTRL+Z)
SEND OK // at this point "datasequence" has reached the server fine
AT+CIPSEND

ERROR

CLOSED (eventual timeout)

I've tried AT+CIPQSEND=1 as well but got ERROR again including specifying length in AT+CIPSEND. Am I missing any AT Commands or is it simply not intended for consecutive use? I would really like to avoid closing and reopening the TCP connection.

Additionally will I have better luck using the AT+HTTP commands?

Shreyas Shreyas · Accepted Answer · 2016-07-25T21:58:23

I've managed to fix this for my situation using the HTTP AT command set. This question was a big help, I was able to do most of the HTTP commands in the set up function of the Arduino code itself. Then in the loop code I simply set the URL with the AT+HTTPPARA command (because this needed to be dynamic - datasequence I mentioned in my first post was tacked on to a URL) and then the AT+HTTPACTION=0 command to execute the GET.

SIM900 GPRS: Consecutive AT+CIPSEND

1 Answers