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PEB 20321
PEF 20321
IOM
-2 Interface
Data Sheet
198
2001-02-14
8.2.3
In an application where the MUNICH32X represents a terminal (TE) interfaced to an S-
bus via an S/T interface transceiver like the QUAT
-S (PEB 2081) and a multipoint
configuration is implemented (i.e. more than one terminal is hooked up to one S-bus),
the D-channel access has to be organized solving collision conditions. This D-channel
access control is specified in ITU I.430. A data collision may occur during the
MUNICH32X starts sending a packet over the D-channel. This collision is detected by
the S/T interface transceiver and reported to the MUNICH32X by asserting the DRDY
pin. Every time a D-channel collision occurs, this event is reported to the protocol
controller. The transmit line (DU) sends continuous
‘
1
’
s. A
“
Late Stop
”
interrupt is
generated and stored in the PCM Tx Interrupt Queue, indicating, that the current frame
has to be retransmitted (refer to PCM Core Interrupt Bit Field description, chapter 12.4)
in case of destructive collision of transmit data.
D-Channel Priority Control
Table 20
Commands and Indications
Activation Indication
Activation Indication priority 1
Activation Indication priority 2
Activation Indication test loop 2
Activation Indication local test loop
Activation Request
Activation Request priority 1
Activation Request priority 2
Activation Request test loop 2
Activation Request local test loop
Activation Request test loop 4
Deactivation Confirmation
Deactivation Indication
Deactivation Request
Power Up
Reset
Resynchronization (loss of framing)
Slip detected in framing
Timing required (to activate IOM
-2)
Test Mode 1
Test Mode 2
U only Activation Indication
U only Activation Request
List of Commands and Indications
Abbreviation
AI
AI8
AI10
AI2
AIL
AR
AR8
AR10
AR2
ARL
AR4
DC
DI
DR
PU
RES
RSY
SLIP
TIM
TM1
TM2
UAI
UAR