Functions
INSYS GSM 4.3 I4
40
11.6
Data Flow Control (Handshake)
The data flow control ensures that the data transfer is interrupted as soon as the modem
buffer exceeds a certain level. Two data flow control options are available: Via the con-
trol lines RTS and CTS, or via the control characters XON/XOFF which are inserted into
the data stream.
11.6.1
Hardware Data Flow Control (RTS/CTS)
The hardware data flow control works in two directions. When the critical buffer level is
exceeded, the modem will set the CTS line to "low" and will thus indicate to the applica-
tion to interrupt the data flow. When the buffer is emptied sufficiently for the INSYS
GSM 4.3 I4 to be able to receive data again, the CTS line is set to "high". Reversely, the
application can also indicate to the INSYS GSM 4.3 I4 to interrupt the data flow. This is
done via the RTS line. If it is set to "low", the modem will interrupt the data flow to the
application. The application will set it to "high" to request data from the INSYS GSM 4.3
I4.
The data flow control with RTS/CTS behaviour is active by default.
Configuration with HSComm
Select the
type of data flow control
or switch it off completely on the "Basic
Settings" tab in the "Handshake" panel.
Configuration with AT commands
To switch the
data flow control
on and to set
the type to
RTS/CTS
, use
AT\Q3
To switch the
data flow control
off, use
AT\Q0
Summary of Contents for GSM 4.3 I4
Page 1: ...Manual INSYS GSM 4 3 I4 Dec 09 ...
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Page 77: ...INSYS GSM 4 3 I4 Index 77 Usage according to the regulations 6 Voice connection 46 ...
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