Specifications

Chapter 10 – Internet Service Commands
Multi-Tech Systems, Inc. AT Commands for EDGE (E1) Modems (S000474A) 167
10.8 AT^SISW Internet Service Write Data
Description: The AT^SISW command triggers a write operation (upload) and queries the amount of data
already sent, but not acknowledged at the TCP layer. The write operation may be run in binary
mode, or in interactive text mode.
The AT^SISW write command may return the following errors:
• "+CME ERROR: operation failed" if there is a problem on application, socket, PPP or
GPRS/GSM level. The AT^SISE command and the "^SIS" URC offer additional error
information.
• "+CME ERROR: operation temporary not allowed" e.g. if the service has not network
resources allocated.
• "+CME ERROR: operation not allowed" e.g. if the service is not configured.
Syntax: Test Command: AT^SISW=?
Response: OK
Write Command: AT^SISW=<srvProfileId>, <reqWriteLength>[, <eodFlag>[, <mode>[,
<optServParam>]]]
Response: ^SISW: <srvProfileId>, <cnfWriteLength>, <unackData>
Number of data bytes as specified by <cnfWriteLength>.
OK
ERROR
+CME ERROR: <err>
Unsolicited Result Code:
^SISW: <srvProfileId>, <urcCauseId>
Data availability status of the Internet service configured with AT^SISS has changed. The URC is issued when
the service is ready to accept new user data.
The URC is disabled in polling mode. See AT^SCFG, parameter "Tcp/WithURCs", <tcpWithUrc>.
Parameters:
<srvProfileId>
<srvProfileId> 0 ... 9 specified with AT^SISS.
<reqWriteLength>
0...1500
Specifies the number of bytes to be sent with AT^SISW or, if set to 0, requests the amount of data already sent
with AT^SISW but not yet acknowledged:
• Parameter <reqWriteLength> may be 1...1500 bytes to specify the amount of data to be sent with AT^SISW.
• If parameter <reqWriteLength> equals 0, AT^SISW does not expect any data, but a normal query is
perfumed. This allows the application to explicitly request, in particular at the end of an upload job, the
amount of unacknowledged data at the TCP layer indicated by <unackData>.
• In interactive text mode, <reqWriteLength> must be set to any value greater than 0 (but not necessarily the
precise number of bytes). If set to 0 in interactive text mode, <reqWriteLength> would be interpreted as
query for unacknowledged data and, thus, prevent data transfer.
• If Socket service is selected with UDP protocol
- <reqWriteLength>=0 can be used to send an empty UDP packet;
- it is recommended that the size of each data packet be limited to 1472 bytes. Otherwise, it is possible
that the following URC occurs: "^SIS: <id>, 0, 9, The supplied buffer was too small / large".
<eodFlag>
End of data indication flag.
Parameter is ignored for HTTP, POP3, FTP download, Socket with UDP protocol.
0 No end of data. Other data may follow to be transmitted via the Internet service. Default. This is the default
value if the parameter is omitted (0 will be assumed).
1 End of data is signaled to the Internet Service. Further AT^SISW write commands return an error response.
However, reading data may be possible. The <eodFlag> is effective only if the <reqWriteLength> equals
<cnfWrite-Length>, in particular if the <reqWriteLength> equals 0.
If <mode> equals 1 the <eodFlag> is effective only if the write operation has been finished with CTRL-Z.
<mode>
Control how the application provides the data bytes to be sent.
0 Binary mode. Default. This is the default value if the parameter is omitted (0 will be assumed).
This mode allows sending a number of bytes defined with parameter <reqWriteLength>.
1 Interactive text mode
This mode allows the user to type and send 8-bit ASCII characters while the service is open. Ctrl-Z
terminates data input and causes the data to be transferred.
Interactive text mode requires that the <reqWriteLength> is set to any value greater than 0 (though it is not
necessary to specify the precise number of bytes). In this case the <cnfWriteLength> parameter indicates
the maximum length of the data stream without control character CTRL-Z. The <txCount> counter is
incremented only by the portion of data actually transmitted.
In interactive text mode, the following characters are predefined as control codes: