13.3.1.2. Configuring the Modem 
In order to be able to make the configuration settings, the modem
must be connected to a PC and a terminal emulation program (HyperTerminal)
must be started on the PC.
IMPORTANT:
The Pocket ISDN TA modem from INSYS
Microelectronics, S30122-X7551-X AYA422 is recommended for
use as an IPDA survivability modem with ISDN interface.
The following must be set if they were not already set by default:
- The baud rate at the modem’s serial interface must be set to 115200 bauds which is mostly covered via the auto-detect mode. Modems that do not support the 115200 baud rate at the serial interface are unsuitable for use with IPDA.
- Auto-Answer must be switched off.
- The local echo must be switched off.
- The modem response to commands must be shown in plain text (in long form), i.e. as text “RING“, “CONNECT“, etc.
- Neither error correction nor compression must be activated in the modem. This is performed by the PPP itself.
- The software handshake (XON/XOFF) must be deactivated.
- For ISDN modems: the B-channel protocol: HDLC - PPP protocol (“Async to sync” conversion, asynchronous PPP, single link PPP)
- For analog modems: set the line bit rate permanently on both modems to save negotiation time. In response to the modem’s “RING“ message, the HG 3575 sends the “ATA” command to the modem which must report “CONNECT“ within 60 seconds.
First the factory defaults must be restored
AT&F
The parameters specified above must then be set
For modem Pocket ISDN TA
- Auto-Answer must be switched off:
ATS0=0 - The local echo must be switched off:
-
ATEor generallyATE0
At least the configuration must be saved:
AT&W