SimCom SIM5300E At Command Manual page 163

Execution Command
AT+CIPSEND
response">", then
type data for send,
tap CTRL+Z to send, tap ESC to
cancel the operation
Parameters
Reference
SIM5300E AT Command Manual V1.02
If sending is successful:
When +CIPQSEND=0
<n>,SEND OK
When +CIPQSEND=1
DATA ACCEPT:<n>,<length>
If sending fails:
<n>,SEND FAIL
Response
This Command is used to send changeable length data.
If single IP connection is established (+CIPMUX=0)
If connection is not established or module is disconnected:
If error is related to ME functionality:
+CME ERROR <err>
If sending is successful:
When +CIPQSEND=0
SEND OK
When +CIPQSEND=1
DATA ACCEPT:<length>
If sending fails:
SEND FAIL
Note:
This Command can only be used in single IP connection mode
(+CIPMUX=0) and to send data on the TCP or UDP connection that has
been established already. Ctrl-Z is used as a termination symbol. ESC is
used to cancel sending data. There are at most <size> bytes which can
be sent at a time.
<n> A numeric parameter which indicates the connection number
<size> A numeric parameter which indicates the data length sent at a time
<length> A numeric parameter which indicates the length of sending data,
it must be less than <size>
Note:
The data length which can be sent depends on network status.
Set the time that send data automatically with the Command of
AT+CIPATS.
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