peb20560 Infineon Technologies Corporation, peb20560 Datasheet - Page 357

• Manufacturer Part Number: peb20560
• Description: Dsp Oriented Pbx Controller Doc
• Manufacturer: Infineon Technologies Corporation

6.3.2
PBXs may use multiple line cards with one DOC on each line card.
Figure 6-6
The following initialization sequence is recommended after reset:
1. One DOC, selected by the µP as system master, generates free running master clocks
2. One DOC, connected to the central office is selected by the µP as clock master. This
Semiconductor Group
PFS and PDC2/4/8 used for FSC and DCL generation on all DOCs/line cards.
The system master is selected by the µP via a line card code (or DOC code).
DOC synchronizes to the central office clock via its trunk line (refer to the Figure 6-5)
and generates a reference clock REFCLK for system master resynchronization.
REFCLK = XCLK divided by 4 or 3 or it equals XCLK.
t/r
U
S0/T
U
Subscribers
t/r
U
S0/T
U
PN
K
PN
K
PBX with Multiple DOCs
Clock Synchronization in a PBX with Multiple DOCs
OCTAT -P
OCTAT -P
DFE & AFE
DFE & AFE
SICOFI -4
SICOFI -4
QUAT
QUAT -S
IEC-4
IEC-4
R
R
R
R
R
R
-S
MPU
MPU
Line-Card 0
Line-Card n
PEB 20560
PEB 20560
DOC
DOC
RAM
RAM
Backplane
- Priority
- Local Network
- Clocks
- PCM Highway
6-7
Board Code
Local Network
PDC2, PDC4, PDC8
PFS
REFCLK
PCM
Board Code
Local Network
PDC2, PDC4, PDC8
PFS
REFCLK
PCM
Backplane
Applications
PEB 20560
ITS10113
2003-08