PEF2054 SIEMENS [Siemens Semiconductor Group], PEF2054 Datasheet - Page 84

• Manufacturer Part Number: PEF2054
• Description: ICs for Communications
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

transceivers (ISDN) or codecs (analog), and the line card controller, the EPIC. The line
card controller provides the connection to the switch backbone. The IOM-2 bus
time-multiplexes data, control, and status information for up to 8 ISDN transceivers or up
to 16 codec/filters over a single full-duplex interface.
Figure 22 shows the IOM-2 frame structure for the line card. It consists of 8 individual
and independent IOM channels, each having a structure similar to the IOM-1 channel
structure. The main difference compared to IOM-1 is the more powerful monitor channel
performance. Monitor messages of unlimited length can now be transferred at a variable
speed, controlled by a handshake procedure using the MR and MX bits. The C/I channel
can have a width of 4 bits for ISDN applications or of 6 bits for analog signaling
applications.
rate. Frames are delimited by an 8 kHz frame synchronization signal (FSC). The bit
timing and FSC position is identical to the non-multiplexed IOM-1 case.
The line card version of the IOM
Figure 22
IOM
Semiconductor Group
®
-2 Frame Structure for Line Card Applications
(4096 kHz)
(2048 kbit/s)
(2048 kbit/s)
Time-Slot
Number
FSC
(8 kHz)
DCL
DD#
DU#
SIG : Signaling Channel
B1 : 64 kbit/s Channel
B2 : 64 kbit/s Channel
D : 16 kbit/s Channel
C/I : Command/Indication Channel
MR : Monitor Handshake Bit "Receive"
MX : Monitor Handshake Bit "Transmit"
IOM Ch. 0
IOM Ch. 0
0 1 2 3 4 5 6 7 8
R
R
B1 Channel
8 Bits
IOM Ch. 1
IOM Ch. 1
R
R
IOM Ch. 2
IOM Ch. 2
R
R
B2 Channel
®
-2 provides a connection path between line
8 Bits
84
IOM Ch. 3 IOM Ch. 4 IOM Ch. 5 IOM Ch. 6 IOM Ch. 7
IOM Ch. 3
R
R
IOM Ch. 4
Monitor Channel
R
R
8 Bits
IOM Ch. 5
ISDN:
Analog:
R
R
IOM Ch. 6
D
Application Hints
Control Channel
R
R
SIG
8 Bits
C/I
IOM Ch. 7
PEB 2055
PEF 2055
R
R
ITD08037
M
M M
R X
R
31
M
X