User`s manual
Bit(s)
Designation
00-01
(Maintenance)
02-03
-
04-05
Extended Address
Read
06
-
07-09
(Maintenance)
10
Sync Select
11,12 (Maintenance)
13
Receiver Enable
14 (Maintenance)
Table
3-3
Line Control Register Bit Assignments
(For
Synchronous Line Cards)
Function
Unused
For the secondary register selected by
SRS
00-03
and
08-11,
these bits display the con-
tents
of
bits
16
and 17, respectively. This en-
ables the program
to
read the extended address
bits
of
the current address and control table base
address secondary registers.
Unused
For the line selected by SRS
00-03,
this bit sets
Sync A character or Sync B character, depending
on whether this bit
is
set to zero or one, respec-
tively, at
LCR
15
set time. Cleared by Initialize.
Sync character encoding
is
discussed in Chapter 2.
When set
to
one at LCR
15
set time, causes the
receiver for the line set in
SRS
00-03
to
search
for the synchronization character(s) in the input
bit
stream. When the synchronization character(s)
is
found, the Microprocessor sets the Receiver
Active bit in the
line
State secondary register.
LCR
13
must be set
to
one
to
enable reception
on
a line following Initialize. This bit
is
not
used for
resynchronization during reception.
To resynchronize during reception, the Receiver
Resynchronize
bit
in the
line
State secondary
register
is
set
to
one.
To
shut down reception in a line, the line number
is
set in SRS
00-03
and LCR
13
is
set
to
zero
at
LCR
15
set time. The Receiver Resynchror..iza-
tion bit in the
line
State secondary register
is
then set.
Cleared
by
Initialize.
3-14
Read/Write
-
-
Read only
-
-
Write
-
Write
-