XR68C681 Datasheet, PDF (37/75 Pages) Exar Corporation – CMOS Dual Channel UART (DUART)

XR68C681
Input
Port
#,
#,
#,
#,1
#,=
#,6
Alternate Function(s)

 4
   $ 
 (  + '   
84  (% (  (% '( :" +  
 + '( 

*4
   $ 
 (  + '   *
84  (% (  (% '( : +  
 + '(

D254
 .(  2! 
'3 # 
5
*4 2! 
'3 (  + '( '   *
5
4 2! 
'3 (  +  %( '  
5
4 2! 
'3 (  + '( '  
5
*4 2! 
'3 (  +  %( '   *
Approach to Program Alternate Functions
#, '  -$  + '( %  
 ( 
& %( -  M=N J    $($ $(%'%%(
  (% + '( " % % Section G.3
#, '  -$  + '( %  
* ( 
& %( - *M=N J    $($ $(%'%%(
  (% + '( " % % Section G.3
#, '  -$  + '( %   ! 
''3 (  +  
 .( & %( -
M/4=N J
M" " N    $($ $(%'%%( (    ++'
+  (% '( % % Section D.2
#, ' %  -$  + '( %   ! 
''3 (  +   '( + '   * & %( -

*M@4=N J M" " " N +   /5
'3" 
*M@4=N
J M" " " N +   5
'3
#,1 '  -$  + '( %   ! 
''3 (  +    %( + '   & %( -

 M14N J M" " " N +   /5
'3" 
 M14N
J M" " " N +   5
'3
#,= '  -$  + '( %   ! 
''3 (  +   '( + '   & %( -

 M@4=N J M" " " N +   /5
'3" 
 M@4=N
J M" " " N +   5
'3
#,6 '  -$  + '( %   ! 
''3 (  +    %( + '   * & %( -

*M14N J M" " " N +   /5
'3" 
*M14N
J M" " " N +   5
'3
Table 12. Listing of Alternate Function for the Input Port Pins
E.2 Input Port Configuration Registers (IPCR)
  #  ,
 +(-( -(% (%  H$ &I
-(%   %%   +( -  + '( %4
     % 3   (' +   + (   ( % 4
#,  #,1" % '  -$ -(' %" %( '   % $
+  (% -(%
     % 3    '  -(' % +  %
+ (  ( %

 %C &"   #  ,
 +(-( -(% (%
+ '( & $(($ (   %'( %4
 *(% @  =4 H
 - ( :-(' I #$ (+('( (%
 *(% 1 4   '  % + #  ,( % #,  #,1
  ( + +   #  ,
 +(-( -(% (%
% $  ( Table 13.
Bit 7
 #,1
 J 8
 J E%
Bit 6
 #,
 J 8
 J E%
Bit 5
 #,
 J 8
 J E%
Bit 4
 #,
 J 8
 J E%
Bit 3
#,1
 J :
 J 9(-
Bit 2
#,
 J :
 J 9(-
Bit 1
#,
 J :
 J 9(-
Table 13. Bit Format of the Input Port Configuration Register (IPCR)
(+ $(%'%%( + ' (+($" ( (  (% -(% +%
Bit 0
#,
 J :
 J 9(-
 
1@