ds3102 Maxim Integrated Products, Inc., ds3102 Datasheet - Page 86

• Manufacturer Part Number: ds3102
• Description: Stratum 3 Timing Card Ic With Synchronous Ethernet Support
• Manufacturer: Maxim Integrated Products, Inc.

Register Name:
Register Description:
Register Address:
Bit #
Name
Default
Note: See Section
Bit 7: Averaging (AVG). When this bit is set to 1 the T0 DPLL uses the averaged frequency value during holdover
mode. When MANHO = 1 in the
Bit 6: Fast Averaging (FAST). This bit controls the averaging rate used in the T0 DPLL’s frequency averager. Fast
averaging has a -3dB response point of approximately 8 minutes. Slow averaging has a -3dB response point of
approximately 110 minutes. See Section 7.7.1.6.
Bit 5: Read Average (RDAVG). This bit controls which value is accessed when reading the HOFREQ field: the
manual holdover frequency or the T0 DPLL’s averaged frequency. This allows control software, optionally, to make
use of the averager and manual holdover mode in a software-controlled holdover algorithm. See Section 7.7.1.6.
Bits 4 and 3: Mini-Holdover Mode (MINIHO[1:0]). Mini-holdover is the state of the T0 DPLL where it is in the
locked state but has temporarily lost its input. In mini-holdover the DPLL behaves exactly the same as in holdover
but with holdover frequency selected as specified by this field. See Section 7.7.1.7.
Bits 2 to 0: Holdover Frequency (HOFREQ[18:16]). See the
Rev: 012108
____________________________________________________________________________________________ DS3102
0 = Not averaged frequency; holdover frequency is either manual (MANHO = 1) or instantaneously frozen
1 = Averaged frequency (averaging rate set by the FAST bit below)
0 = Slow frequency averaging
1 = Fast frequency averaging
0 = Read the manual holdover frequency value previously written
1 = Read the averaged frequency
00 = Frequency determined in the same way as holdover mode
01 = Frequency instantaneously frozen (i.e., as if AVG = 0)
10 = Frequency taken from fast averager (i.e., as if AVG = 1 and FAST = 1)
11 = Frequency taken from slow averager (i.e., as if AVG = 1 and FAST = 0)
8.3
AVG
7
1
for important information about writing and reading this register.
FAST
6
0
MCR3
HOCR3
Holdover Configuration Register 3
40h
register, this bit is ignored. See Section 7.7.1.6.
RDAVG
5
0
4
0
MINIHO[1:0]
HOCR1
1
3
register description.
2
0
HOFREQ[18:16]
1
0
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0
0