AT Commands Reference Manual - wireless netcontrol GmbH

RS232 Multiplexer Feature
RS232 Multiplexer Feature
The MUX provides multiple logical RS232 communication channels between the DTE and H24
over one physical RS232/UART connection. This service enables the DTE device to run multiple
applications (such as External PPP, CSD, ODM, SMS and voice calls) while communicating
simultaneously with the H24.
System Overview
The MUX service in H24 provides two virtual channels for DTE.
These MUX entities communicate with each other and provide data connection management,
which includes establishment, control, release and data transfer between IDLC.
The MUX over RS232/UART is a software module which enables one serial interface to transmit
data to two different DTE applications. This is achieved by providing two virtual channels using
a multiplexer (MUX).
Both H24 and the DTE application must have MUX components to allow communication with
multiplexer protocol.
When in MUX mode H24 AT commands and data are encapsulated into packets. Each packet has
channel identification and may vary in length.
Product Architecture
Figure 3-7 shows the current product architecture (MUX).
data control not in use
DTE 1 DTE 2 DTE 3 … DTE n
MUX 27.010
Serial
Serial
MUX 27.010
Ch. 1 Ch. 2 Ch. 3 … Ch. n
data control
not in use
H24
Figure 3-7: MUX Architecture
MUX Channels Definitions
H24 supports two channels configuration.
In this configuration DLC1 will be a data channel while DLC2 will be the control channel.
These channels will apply to specification defined within Multi-Channeling feature [1].
3-370 H24 - AT Commands Reference Manual April 15, 2010