Dlc Release; Close-Down Procedure; Multiplexer Control Channel; Figure 9: Dlc Release - Siemens Mux_guide_v06 User Manual

Multiplexer User's Guide
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4.3.4 DLC release

No provision is made to repeat the request if no response is received.
Customer
µC

4.3.5 Close-down procedure

To close down the multiplexer follow these two steps:
•
First, disconnect all DLCIs by sending the DLCI Release command within the multiplexer
control channel frame (as described in section 4.3.6).
•
Finally, close down the multiplexer control channel (DLCI = 0) by sending the multiplexer
close down command CLD (see section 4.3.7). After this, both the "initiating station" and
the "responding station" revert to AT command mode.
Before closing the multiplexer make sure that there is no ongoing activity on one of the
channels. For example, check that voice, CSD or GPRS connections have ended and wait
until all pending AT command responses are received.

4.3.6 Multiplexer control channel

DLCI = 0
1 Octet
The commands are sent as information in the multiplexer control channel frame.
Type field:
Bit 1 Bit 2
EA C/R
EA bit: Extension bit.
In the last octet of the sequence the EA bit = 1, otherwise = 0.
If there is only on octet, EA bit = 1 is set.
C/R bit: Indicates whether the sequence is a command or a response.
T-bits: Coding of the command type.
Mux_guide_v06
DISC: P = 1
UA: F = 1
DM: F = 1 responding station is
already disconnected

Figure 9: DLC release

Type Length Value 1
n Octets 1 Octet
Information Field

Figure 10: Multiplexer control channel

Bit 3 Bit 4
T1 T2
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Value 2 Value n
.....
1 Octet 1 Octet
Bit 5 Bit 6
T3 T4
s
m
o b i l e
GSM
engine
Bit 7 Bit 8
T5 T6
30.06.2004