RELEASED
PM73123 AAL1GATOR-8
DATASHEET
PMC-2000097
ISSUE 2
8 LINK CES/DBCES AAL1 SAR
a result, any writes to this word after TALP generates the first cell will have no
affect.
Field (Bits)
Description
TX_HEAD(5)
(15:8)
Fifth header byte that contains the precalculated
HEC word. TALP neither calculates nor verifies the
HEC. Initialize to the proper value.
Not used
(7:0)
Write with a 0 to maintain compatibility with future
software versions.
QUE_CREDITS Word Format (0BH)
After initialization this word is read only. The word is maintained by CSD.
Field (Bits)
Description
FRAME_REMAINDER
(15:14)
A 2-bit quantity representing the remainder of the
division operation the CSD performs when
converting the frame differential (expressed in
frames) to the frame differential (expressed in
eighths of multiframes). This quantity is maintained
by the CSD. Initialize to 00b except in DBCES mode
where this value must be calculated. The frame
remainder field must be initialized correctly. The
equation is as follows:
Remainder = frame_diff MOD N (where N=2 for E1; N=3 for
T1)
STR_PTR_SENT
Indicates a structure pointer has been sent in the
current set of 8 cells. Initialize to “0”.
(13)
TEST_SPDUP_NULL
(12)
A test mode bit which speeds up the frequency of
the generation of Null cells in DBCES mode to less
than 4 ms in between cells. Initialize to “0”.
BITMASK_SENT
Indicates the bitmask has been sent in the current
set of 8 cells. Initialize to “0”.
(11)
FIRST_CELL_SCHED
(10)
Indicates the first cell has been scheduled for this
queue. Initialize to 0.
PMC-SIERRA, INC. PROPRIETARY AND CONFIDENTIAL
195
PMC [ PMC-SIERRA, INC ]
