RELEASED
PM73123 AAL1GATOR-8
DATASHEET
PMC-2000097
ISSUE 2
8 LINK CES/DBCES AAL1 SAR
Field (Bits)
Description
QUEUE_CREDITS
(9:0)
A 10-bit quantity representing the number of byte
credits accumulated for the queue. It is measured in
eighths (three LSBs are fractional bits).
Initialize to the following in non-DBCES mode:
UDF-ML: 178H (47 x 8)
SDF-FR, single DS0, no pointer: 178H (47 x 8)
SDF-FR (except above): 177H (46.875 x 8)
AAL0: 180H (48 x 8)
Partial Cells: #Bytes per cell x 8
SDF-MF, E1, single DS0: 187H ((46.875 + 2) * 8)
SDF-MF T1, single DS0: 17FH ((46.875 + 1) * 8)
SDF-MF E1, two DS0s: 17FH ((46.875 + 1) * 8)
SDF-MF (except above): 177H (46.875 * 8)
UDF-HS and Low_CDV mode: NOT USED
For DBCES mode the credits written during setup
must be accurate. The equations are as follows:
Frame_diff = ROUNDUP(47/num_chan)
Data_credits = frame_diff * num_chan
Sig_per_1/8th = [ROUNDDOWN((num_chan+1)/2)] / 8
Sig_credits = ROUNDDOWN[(frame_diff/N) * sig_per_1/8th]
(where N=2 for E1; N=3 for T1)
Credit_reg = data_credits + sig_credits + 1 + bitmask_size
(the 1 accounts for the structure pointer)
CSD_CONFIG Word Format (0CH)
This word is maintained by the microprocessor.
PMC-SIERRA, INC. PROPRIETARY AND CONFIDENTIAL
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PMC [ PMC-SIERRA, INC ]
