peb3456e Infineon Technologies Corporation, peb3456e Datasheet - Page 90

• Manufacturer Part Number: peb3456e
• Description: Channelized T3 Termination, With Ds3 Framer, M13 Multiplexer, T1/e1 Framers And 256-channel Hdlc/ppp Controller
• Manufacturer: Infineon Technologies Corporation

4.7.1
The framing structure is defined by the contents of time-slot 0 (refer to Table 4-8).
Table 4-8
Alternate
Frames
Frame Containing the
Frame Alignment Signal
Frame not Containing
the Frame Alignment
Signal
1)
2)
3)
4)
4.7.1.1
Synchronization status is reported via bit FRS.LFA. Framing errors are counted by the
Framing Error Counter (FEC). Asynchronous state is reached after detecting 3 or 4
consecutive incorrect FAS words or 3 or 4 consecutive incorrect service words (bit 2 = 0
in time-slot 0 of every other frame not containing the frame alignment word), the
selection is done via bit RFMR.SSC. Additionally, the service word condition can be
disabled. When the framer lost its synchronization an status bit FRS.LFA is generated.
In asynchronous state, counting of framing errors will be stopped.
The resynchronization procedure starts automatically after reaching the asynchronous
state. Additionally, it may be invoked user controlled via bit RCMDR.FRS (Force
Resynchronization: the FAS word detection is interrupted. In connection with the above
conditions this will lead to asynchronous state. After that, resynchronization starts
automatically).
Data Sheet
Si-bits:
Reserved for international use. They are fixed to ‘1’.
Fixed to ‘1’. Used for synchronization.
Remote alarm indication:
In undisturbed operation ‘0’; in alarm condition ‘1’.
S
Reserved for national use. If not used, they should be fixed at ‘1’. Access to received information
via registers RSAW1-3. Transmission via registers XSAW1-XSAW3. HDLC signalling in bits
S
a
a4
-bits:
- S
a8
is selectable.
Doubleframe Format
Synchronization Procedure of the Receiver
Bit
Number
Allocation of Bits 1 to 8 of Time slot 0
1)
1)
Si
Si
1
Frame Alignment Signal
2)
2
0
1
3)
90
A
3
0
4)
S
1
4
a4
S
5
1
a5
Functional Description
S
6
0
a6
PEB 3456 E
S
7
1
a7
05.2001
S
8
1
a8