XR68C681 Datasheet, PDF (17/75 Pages) Exar Corporation – CMOS Dual Channel UART (DUART)

XR68C681
Bit 7
Input Port
Change
 J 8
 J E%
Bit 6
Delta Break
B
 J 8
 J E%
Bit 5
RXRDY/
FFULLB
 J 8
 J E%
Bit 4
TXRDYB
 J 8
 J E%
Bit 3
Counter
Ready
 J 8
 J E%
Bit 2
Delta Break
A
 J 8
 J E%
Bit 1
RXRDY/
FFULLA
 J 8
 J E%
Table 5. Interrupt Status Register - (ISR) Bit Format
Bit 0
TXRDYA
 J 8
 J E%
   ( -  ( $ ' +  % (% (% $+( $ 
ISR[7]: Input Port Change of State:
#+  (% ( (%   -(' HI"    H'  - + %I %
$'$    #,  #,1 ( %   % $ %('  (%
(  & $( -   #,
 (+ #M@N J  #M@N (%
'$    
, % $   #,
 *& $( -  
#,
"   % ( $( 4
   ( $(($ #  , (   '  -$ %
   +(  % +    ($ (  %" +( -
 
 - + 
  $($ $%'(( +   #,
" % %
Section E
,%    ( $     (% (  ' $(( "
  % % $   ( -%4
 A(   ( $     ( +  
!((&
  -(%"
M14N #  (% %"  
% (% %'(+&( -  (' (  ( % % $ (-- 
H#  ,
 -I (  C%
 A(  -(' HI  #M@N
ISR[6] Delta Break Indicator - Channel B:
A   (% ( (% %" ( ( $('%     '   * '(
% $'$   -( ( -   $ +  '($ 3
 (% ( (% '$  %    
, ( 3% 
'   * H22 *2 7
9 802 #82,I
' $   ( +( (     .%
% %   *2 7 ' $(( " % % Section G.2
ISR[5] RXRDYB/FFULLB - Channel B Receiver
Ready or FIFO Full
  + '( +  (% ( (% %'$ & -( -
*M/N #+ -$ %   '( $&
( $(' 5E*" ( ( $('%    %  
' ' + $ (% (   9*  $ (% $&   $ &
 
,  (% ( (% %    ' ' (%  %+$
+   '($ % (+ -(%  9*  $ (% '$
   
, $% 9* #+    %( 
' '% ( 9* +   $ ( "   ( ( 
% -( + 9* (% H$I
#+  (% ( (% -$ % #   ( $('  ::*"
( (% %    ' ' (%  %+$ +    
9*  $    %+ '%% 9*  ' +  (%
( (% '$    
, $% 9*K  $  &
H( -I   # " 3( -  +   ! ' ' #+
 ' ' (% (( - (    '% 9* (% +"
 (% ( (  % -( +   $ ( "    
' ' (% $$ (  9*
ISR[4] TXRDYB - Channel B Transmitter Ready
 (% ("   %" ( $('%   9* (% &  $ (%
$&  ''  ' ' +  
,   ( (%
'$    
, (%   ' '  9*K
 $ (% % -( "     ' ' (%  %+$   
 5E (% %      %( (% ( ((&
 $  $ (% '$      %( (% $(%$

'% $$ (  9*  (    %( (%
$(%$ (    %($
 
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