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XR88C681 Datasheet, PDF (28/99 Pages) Exar Corporation – CMOS DUAL CHANNEL UART (DUART)
XR88C681
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== , $  & %% C !  D
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%%  $"  , $ (% (( - C 'D
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Op-Code (hex)
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2>
2
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Mnemonic
 
 
 
 1
 <
 6
 /
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Restart Address
(hex)

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1
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Table 10. 8080A and 8085 CPU Restart Instructions
Used With Vectored Interrupts
  + "  '  ,  ' ( %  '$ +  +
 % 2  ( %'( %" ( (  -( ! '( -  (%
( %'( & $( -  ,-    ( 
( C % $$ %%D + $%" -
'  (   ' $   C % $$ %%D '( 
 2! 4
#+  '$ C2>/D (% $ $     *% $( -
 #7 '&' "  (% '$ ' % $% (  C
<D ' $  $"  , ( $ / (  
,-     $ - '  (  '   
'( (  & % Table 10
Interfacing the 8080 CPU Module to the XR88C681
DUART for Interrupt Processing
 == , '  ' ' $   5==/=  $
 (  #   ( $  Figure 7  % % 
'   '  ( $  (  +'( - 
5==/=     == , + C !  D
 ' $ (   ' %%( - Please note that (- =
only includes information pertaining to DUART interrupt
servicing.   '('(& %' %  =< '3
0 "  $$ %% *%" '   ( $ +
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 5==/= (  E %  (     ==
, " & --( - (% #7  CD  (% %(-  (%
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,   '  == , % '  $ (% ' 
( %'( " ( ( %%   '(  #7 %(-  +
 == *(( '(  *% (    (% ( "  
#7 %(-  +     $  #7 %(- 
+  ==  '   -(' CD  #7  $
#7 %(- %    $   (   - 
8 ' "   #7  $ #7   -(' CD" 
 +  - ( %    -(' CD"  $
  & %% ( -  +   2  2 ( %
+  7><9<<  *% ++   1  (% C( -D +
 #7  $ #7 %(- % (% % $  ( %    & 
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#7 %(-   '  2 ( % + 1  %%  $"
 $" ( $   (  +  (% $ ('  1 ( 
     +  (% $ (' "  $   >  
( % +  == $ ('   Please note that, in this
example, the value “E716” is hard-wired into the input of
U3  (%  (%  '$ +  C <D ' $
8 ' "  '  (% $ (% - $ (   , $ " (
 $ %"  , ( $ / (  (% ,-
    $  ' - '     '(  
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