ACS8520T Semtech, ACS8520T Datasheet - Page 128

• Manufacturer Part Number: ACS8520T
• Description: Synchronous Equipment Timing Source (SETS) for Stratum 3/4E/4 and SMC Systems
• Manufacturer: Semtech

Address (hex):
Address (hex):
Revision 3.02/October 2005 © Semtech Corp.
ADVANCED COMMUNICATIONS
Register Name
2k_8k_from_T4
Register Name
indep_FrSync/
MFrSync
Bit No.
Bit No.
Bit 7
Bit 7
[5:2]
0
7
6
7A (cont...)
7B
cnfg_sync_pulses
Description
2k_pulse
Register bit to enable the 2 kHz output from TO11
to be either pulsed or 50:50 duty cycle. Output TO3
must be enabled to use “pulsed output” mode on
output TO10, and then the pulse width on TO11 will
be defined by the period of the output programmed
on TO3.
cnfg_sync_phase
Description
indep_FrSync/MFrSync
This allows the option of either maintaining
alignment of FrSync and other clock outputs during
synchronization from the SYNC2K input, or whether
to not maintain alignment to all clocks and so not
disturb any of the output clocks
Sync_OC-N_rates
This allows the SYNC2K input to synchronize the
OC-3 derived clocks in order to maintain alignment
between the FrSync output and output clocks and
allow a finer sampling precision of the SYNC2K
input of either 19.44 MHz or 38.88 MHz.
Not used.
Sync_OC-N_
rates
Bit 6
Bit 6
Bit 5
Bit 5
Description
Description
Bit 4
Bit 4
FINAL
Page 128
(R/W) Register to configure the
Sync outputs available from TO10
and TO11 and select the source
for the 2 kHz and 8 kHz outputs
from T01 - TO7.
8k_invert
(R/W) Register to configure the
behavior of the synchronization
for the external frame reference.
Bit Value
Bit Value
Bit 3
Bit 3
0
1
0
1
0
1
8k_pulse
Value Description
2 kHz TO11 output not pulsed.
2 kHz TO11 output pulsed.
Value Description
MFrSync & FrSync outputs are always aligned with
other output clocks.
MFrSync & FrSync outputs are independent of other
output clocks.
The OC-N rate clocks are not affected by the
SYNC2K input. The SYNC2K input is sampled with a
6.48 MHz precision. 6.48MHz should be provided
as the input reference clock.
Allows the SYNC2K to operate with a 19.44 MHz or
38.88 MHz input clock reference. Input sampling
and output alignment to 19.44 MHz is used when
the current clock input is 19.44 MHz, otherwise
38.88 MHz sampling precision is used.
Bit 2
Bit 2
Default Value
2k_invert
Default Value
Sync_phase
ACS8520 SETS
Bit 1
Bit 1
DATASHEET
www.semtech.com
0000 0000
2k_pulse
0000 0000
Bit 0
Bit 0