ACS8509 SETS
ADVANCED COMMUNICATIONS
Table 14 Register Description (cont...)
FINAL
DATASHEET
Addr.
(Hex)
Register Name
sts_reference_sources
Description
Default Value (Bin)
This is a 3-byte register which holds the status of each of the 4 input reference
sources. The status of each reference source is shown in a 4-bit field. Each bit is
active high. To aid status checking, a copy of each status bit 3 is provided in the
sts_sources_valid register. The status is reported as follows: (Each bit may be cleared
individually.)
13
15
16
cnfg_ref_selection_
priority
Status bit 3 = Source valid (no alarms) (bit 3 is combination of bits (2:0)) (default 0)
Status bit 2 = out-of-band alarm (default 1)
Status bit 1 = no activity alarm (default 1)
Status bit 0 = phase lock alarm (default 0)
Bits (7:4) Status of input reference source <SEC2>.
Bits (3:0) Status of input reference source <SEC1>.
Bits (7:4) Unused.
Bits (3:0) Status of input reference source <SEC3>.
Bits (7:4) Unused.
Bits (3:0) Status of input reference source <SEC4>.
This register holds the priority of each of the 4 input reference sources. The priority
values are all relative to each other, with lower-valued numbers taking higher
priorities. Only the values “1” to “15” (dec) are valid - “0” disables the reference
source. Each reference source should be given a unique number, however two
sources given the same priority number will be assigned on a first in first out basis.
01100110
01100110
01100110
It is recommended to reserve the priority value “1” as this is used when forcing
reference selection via the cnfg_ref_selection register. If the User does not intend to
use the cnfg_ref_selection register then the priority value “1” need not be reserved.
1B
Bits (7:4) Programmed priority of input reference source <SEC2>.
Bits (3:0) Programmed priority of input reference source <SEC1>.
10011000
1D
Bits (7:4) Unused.
11010001
Bits (3:0) Programmed priority of input reference source <SEC3>.
(MSTSLVB=0)
11011100
(MSTSLVB=1)
1E
Bits (7:4) Unused.
Bits (3:0) Programmed priority of input reference source <SEC4>.
11111110
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