XR88C681CP Datasheet, PDF (15/99 Pages) Exar Corporation – CMOS DUAL CHANNEL UART (DUART)

XR88C681
'  "    % -(' $$%%   +%  $ + '( % +        ' $ &   $
-(%%  $(%'%%$ ( $( ( Section G.3
B.2 Command Decoding
2' '   (% E($ ( 
 $ -(% # - "    +  %
 $ -(%%  
 .$(%    %("  .$(%   '("  - ( +'((( -  %(% +   (%' %
' $%   ( + + '
 $ -(% (% % $ ( 
Bit 7
Bit 6
Bit 5
Miscellaneous Commands
 ( - !
Bit 4
Bit 3
Bit 2
Enable/Disable
Receiver
 J 7
 -
 J 2  !
 J (% !
 J 7 ($ $  %
Bit 1
Bit 0
Enable/Disable
Transmitter
 J 7
 -
 J 2  !
 J (% !
 J 7 ;($   %
Table 2. (CRA, CRB) Bit Format for Command Registers of Channels A & B
  + '( +    ( +  
 $ -(%% (% +(& %(- +$  (% ( (% %$  (   
 $(%    %(  $. '(
   ( +  
 $ -(% (% %$  ( 3  %(% + (%' % ' $% Table 3 $+( %  
' $% %%'($ (    ( +  
 $ -(%% Please note that the upper nibble commands
1₁₆ through B₁₆ effects only the performance of Command Register’s Channel 8" ' $%
_/  $ _/
++'% %&%  ' (  ( 
Bit 7




Bit 6




Bit 5




Bit 4




Description
Null Command.
Reset MRn Pointer.
%%  
 H% 
(   (    
Reset Receiver. %   ( $(($ '   
'( % (+  8$ % %  ($
  '( (% $(%$  $   #  (% +% $
Reset Transmitter. %%   ( $(($ '  
 %( % (+  8$ % $  ($
  5  (% +'$   (- 
Table 3. Miscellaneous Commands, Upper Nibble of all Command Registers,
Unless Otherwise Specified (Cont’d Next Page)
 
6