XR68C681 Datasheet, PDF (14/75 Pages) Exar Corporation – CMOS Dual Channel UART (DUART)

XR68C681
Table 1 ( $('%   ' '   (% C($ ( 
H$ -(%%I %%'($ ( ' +  % H$
-(%I (% (%  H$ -(%I (    ( 
 ' (.%&%    22 '  (  (%
H( ( - I   '    -(% ,%   
  %++(! H I (% %$     $ +  & +  % -(%
%&% ( $  +" - ('&"  (  '  %
 * 9"   '  % +    (  ( % (+
+   $$%% +    -(%    +   
-(%" ($(& +( -  & $  ( ''%% 
   -(%    (  ( ' (   H( 
I    -(%  (  $ % ''% 
 (  H22  ,#82I ' $ % 
( 3$   H22  ,#82I ' $ ' 
(%%$ & (( -   ( $    (
'  .% ' $ -(%  +"  $
-(%%" ( (  -( '  "    % -('
$$%%   +%  $ + '( % +      
 ' $ &   $ -(%%  $(%'%%$ (
$( ( Section G.3
B.2 COMMAND DECODING
2' '   (% C($ (  ' $ -(% #
- "    +  % ' $ -(%%  
 .$(%    %("  .$(%  
'("  - ( +'((( -  %(% +  
(%' % ' $%   ( + + '
' $ -(% (% % $ 
Bit 7
Bit 6
Bit 5
Miscellaneous Commands
 ( - !
Bit 4
Bit 3
Bit 2
Enable/Disable Transmitter
 J 8
 -
 J 2  !
 J (% !
 J 8 ;($
  %
Bit 1
Bit 0
Enable/Disable Receiver
 J 8
 -
 J 2  !
 J (% !
 J 8 ($
$  %
Table 2. Command Register - CRA, CRB
  + '( +    ( +   ' $ -(%% (% +(& %(- +$  (% ( (% %$  (    
$(%    %(  $. '(
   ( +   ' $ -(% (% %$  ( 3  %(% + (%' % ' $% Table 3
$+( %   ' $% %%'($ (    ( +   ' $ -(%% ,%       (
' $% /  - *_/ ++'%  &   + ' + ' $ -(%.% '   9" ' $%
/
 - _/ ++'% %&%  ' (  ( 
 
=