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RELEASED
PM73122 AAL1GATOR-32
DATASHEET
PMC-1981419
ISSUE 7
32 LINK CES/DBCES AAL1 SAR PROCESSOR
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
192
Field (Bits)
Description
CLK_SOURCE_TX
(6:4)
Selects TL_CLK source. This value will override the
setting defined by the TLCLK_OUTPUT_EN input. If
switching from an external to an internal clock or visa
versa, make sure there are not two clocks driving
simultaneously.
In Direct Low Speed mode all options are valid. In SBI
mode all options except “110” are valid. In high speed
mode the only valid options are “000” and “001”. The
field is ignored in H-MVIP mode.
000
Use external clock. (TL_CLK is an input).
001
(not supported for DS3 over SBI)
LOOPED – Use RL_CLK as the clock source.
010
nominal (T1 or E1) frequency from SYS_CLK.
NOMINAL Synthesized – Generate a clock of the
011
frequency based on the received SRTS values.
SRTS Synthesized- Generate a T1/E1 clock
100) ADAPTIVE Synthesized- uses receive buffer depth
to generate a T1/E1 clock.
101) Externally controlled Synthesized: Generate a
T1/E1 clock frequency based on the values provided by
CGC_SER_D pin. This mode is used for external
implementations of SRTS or Adaptive clocking.
110) Use common external clock (CTL_CLK) (only valid
in low speed mode)
111) If in Direct Low Speed Mode, use common external
clock (CTL_CLK) and drive TL_SIG data onto TL_CLK
pin. If in SBI mode then use the nominal T1/E1 clock
sourced by the SBI SIPO. This is required when this line
sources data to an SBI INSBI Synchronous Tributary.
Not valid in other modes.
Note for Dual DS3 mode see important configuration
note in High Speed Operations Section 14.2.4.4