ACS8525T Semtech, ACS8525T Datasheet - Page 66

• Manufacturer Part Number: ACS8525T
• Description: Line Card Protection Switch for SONET/SDH Systems
• Manufacturer: Semtech

Address (hex):
Address (hex):
Revision 3.01/August 2005 © Semtech Corp.
ADVANCED COMMUNICATIONS
Register Name
Register Name
Bit No.
Bit No.
Bit 7
[5:0]
Bit 7
7
6
5
47 (cont...)
48
cnfg_freq_divn
[13:8]
Description
divn_value[13:8]
This register, in conjunction with Reg. 46
(cnfg_freq_divn) represents the integer value by
which to divide inputs that use the DivN pre-divider.
The DivN feature supports input frequencies up to a
maximum of 100 MHz; therefore, the maximum
value that should be written to this register is 30D3
hex (12499 dec). Use of higher DivN values may
result in unreliable behaviour.
cnfg_monitors
los_flag_on_
TDO
Description
Not used.
los_flag_on_TDO
Bit to select whether the main_ref_fail interrupt
from DPLL1 is flagged on the TDO pin. If enabled
this will not strictly conform to the IEEE 1149.1 JTAG
standard for the function of the TDO pin. When
enabled the TDO pin will simply mimic the state of
the main_ref_fail interrupt status bit.
ultra_fast_switch
Bit to enable ultra-fast switching mode. When in this
mode, the device will disqualify a locked-to source
as soon as it detects a few missing input cycles.
Bit 6
Bit 6
ultra_fast_
switch
Bit 5
Bit 5
Description
Description
ext_switch
Bit 4
Bit 4
divn_value [13:8] (divide input frequency by n)
FINAL
Page 66
(R/W) Bits [13:8] of the division
factor for inputs using the DivN
feature.
(R/W) Configuration register
controlling several input
monitoring and switching options.
PBO_freeze
Bit Value
Bit Value
Bit 3
Bit 3
0
1
0
1
-
-
Value Description
The input frequency will be divided by the value in
this register plus 1. i.e. to divide by 8, program a
value of 7.
PBO_en
Value Description
-
Normal mode, TDO complies with IEEE 1149.1.
TDO pin used to indicate the state of the
main_ref_fail interrupt status. This allows a system
to have a hardware indication of a source failure
very rapidly.
Currently selected source only disqualified by Leaky
Bucket or frequency monitors.
Currently selected source disqualified after less
than 3 missing input cycles.
Bit 2
Bit 2
Default Value
Default Value
ACS8525 LC/P
Bit 1
Bit 1
DATASHEET
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0011 1111
0000 0100*
Bit 0
Bit 0