Phone Connection; Data Buffer For Serial Data Transmission - INSYS 56k Small INT 2.0 Manual Manual

INSYS Modem 56k Small INT 2.0
12.2.2

Phone connection

The automatic negotiation of the baud rate and the modulation standard enables the
INSYS Modem 56k Small INT 2.0 to negotiate the largest possible connection speed to the
remote terminal while the connection is established. The speed depends on the settings
and the abilities of the modem at the remote terminal. Via the modulation standard, the
connection speed can be set through the phone line. If nothing is defined, the INSYS Mo-
dem 56k Small INT 2.0 will automatically try to determine the optimum connection pa-
rameters.
The function is active as default.
Configuration with HSComm
A direct configuration with the HSComm is not intended. The AT command to
define a fixed baud rate can be sent to the INSYS Modem 56k Small INT 2.0 via
the entry field "Initialization string" (Page 27, Figure 5: HSComm Modem - Tab
Modem, Position 13).
Configuration with AT commands
To configure the modulation standard and
thus the connection speed, use the command:
Please find the possible parameters for this command in the Chapter "AT
Command reference".
To display the current settings:
For a list of possible parameter of the com-
mand, enter:
12.3

Data Buffer for Serial Data Transmission

The INSYS Modem 56k Small INT 2.0 has send and receive buffers. These buffers prevent
the loss of data, in case the application or the remote terminal can not receive data at
this time. The data buffer can be deactivated together with the error correction (bit di-
rect mode). When the buffer is activated, the data flow control should be active to avoid
a buffer overflow in the INSYS Modem 56k Small INT 2.0. If the buffer flows over, the IN-
SYS Modem 56k Small INT 2.0 will perform a reset. Operation without a buffer and error
correction is only useful for special character framings.
The function is active as default.
Configuration with HSComm
Select the type of error correction on the tab Modem in the panel "Phone in-
terface" (Page 27, Figure 5: HSComm Modem - Tab Modem, Position 25). Buff-
ering is active for all options except the option "unbuffered, bit direct". To de-
activate the buffer (and simultaneously the error correction), select "un-
buffered, bit direct".
AT+MS=<modulation>
AT+MS?
AT+MS=?
Functions
31