ZyXEL Communications Omni TA128 - Manual (Page 124)

112
16
AT Command Set
Reference
Operation Modes of the DTE Interface
There are two operation modes for the DTE interface:
•
Simplex mode - used for conventional AT Command
operation.
•
Multiplex mode - used as an internal interface for ZyXEL
CAPI drivers.
Simplex mode
In simplex mode, the TA128 is used just like an ordinary TA. The
DTE interface will be either in the command state or in the data
state. At most, only one data connection session is possible at any
time.
A number of different AT Commands can be used to invoke
various functions. The simplex mode is designed for AT Command
users. The guides and descriptions throughout the rest of this
manual, if not otherwise specified, are applicable to this mode. The
power-on default of the DTE interface is in simplex mode as well.
Multiplex mode
The multiplex mode is designed for ZyXEL CAPI drivers. It can
also be used by third parties to develop various drivers on different
platforms for public domain or for commercial purposes.
The commands or data are packetized. Each packet has its own
destination address. All the DTE channels can be accessed
individually by way of multiplexing.