ZL30402
Data Sheet
Hardware Control
Software Control
HW = 1
HW = 0
Pins
MS2
MS1
FCS
MS2
MS1
FCS
C
O
N
T
C
O
N
T
RefSel
RefAlign
AHRD
MHR
R
O
L
R
O
L
RefSel
RefAlign
µP
LOCK
HOLDOVER
FLIM
LOCK
S
T
A
T
U
S
S
T
A
T
U
S
PAH
PAFL
SAH
SAFL
HOLDOVER
Figure 6 - Hardware and Software Control options
4.1 Hardware Control
The Hardware control is a subset of software control and it will only be briefly described with cross-referencing to
Software control programmable registers.
4.1.1 Control Pins
The ZL30402 has six dedicated control pins for selecting modes of operation and activating different functions.
These pins are listed below:
MS2 and MS1 pins: Mode Select: The MS2 (pin 19) and MS1 (pin 18) inputs select the PLL mode of operation.
See Table 1 for details. The logic level at these inputs is sampled by the rising edge of the F8o frame pulse.
FCS pin: Filter Characteristic Select. The FCS (pin 9) input is used to select the filtering characteristics of the
Core PLL. See Table 2 on page 19 for details.
MS2
MS1
Mode of Operation
0
0
1
1
0
1
0
1
Normal mode
Holdover mode
Free-run
Reserved
Table 1 - Operating Modes and States
18
Zarlink Semiconductor Inc.
ZARLINK [ ZARLINK SEMICONDUCTOR INC ]
