User manual

Block Diagram Descriptions
Theory of Operation
3Ć24
(%  %-/18 /!1$ 01/5)$%2 3(% 7%#43)5% 01/#%22/1   6)3( 2823%-
  /.95/,!3),%   !.$  &/1 -/23 /0%1!3)/.2
400/13 #)1#4)318 &/1 3(% -%-/1)%2 !.$ $)!'./23)# #)1#4)318 &/1 31/4",%2(//39
).' !1% ,/#!3%$ /.9"/!1$ ,, !##%22%2 3/   /1 2 !1%
).)3)!3%$ "8 3(%  7%#43)5% 1/#%22/1 "/!1$ 20%#)&)#!,,8 "8 3(%   /1
3(%  #/.31/,,%1 %&%1 3/ 3(% $)2#422)/. /& 3(%  7%#43)5% 1/#%22/1
"/!1$ %!1,)%1 ). 3()2 2%#3)/. &/1 "42 #8#,% 3)-).' ).&/1-!3)/.
(%  %-/18 "/!1$ #/.2)232 /& 3(% &/,,/6).' #)1#4)318
H $$1%22 ,!3#(%2
H $$1%22 $%#/$% !.$ -%-/18 2%,%#3 #)1#4)318
H  !.$ 2823%- 
H %-/18 $!3! "4&&%12
H !)3 23!3% '%.%1!3/1
H !)3 23!3% $)!'./23)#2
H %-/18 #/.&)'41!3)/. 1%!$"!#+
H /.95/,!3),%  !.$ "!33%18 "!#+40
%% )'41% 9 &/1 ! ",/#+ $)!'1!- /& 3()2 "/!1$
Address Latches
()2 #)1#4)318 "4&&%12 !.$ (/,$2 3(% !$$1%22 ,).%2 &/1 3(% 2 2
2 !.$ /3(%1 /.9"/!1$ $%5)#%2 4.3), 3(% %.$ /& 3(% "42 #8#,%
Address Decode and Memory Select
()2 #)1#4)3 #/.2)232 /& ! 01/'1!--!",% !11!8 ,/')#  $%5)#% 3(!3 $%9
#/$%2 3(% !$$1%22 ,).%2 3/ 01/$4#% &)5%  2%,%#3 2)'.!,2 9 !.$
&/41  2%,%#3 2)'.!,2 9  %.!",%2 3(%  6(),%
9 %.!",% 3(%  ,,  !.$  2%,%#3 ,).%2 !1% ,!3#(%$
!.$ 3(% ,!3#( /430432 !1% ./1-!,,8 %.!",%$ (),% 3(% ,!3#( %.!",% 2)'.!, )2
()'( 3(% ,!3#( /430432 !1% 1%20/.2)5% 3/ #(!.'%2 /. 3(% ).0432 6(),% 3(%
,!3#( %.!",% 2)'.!, )2 ,/6 3(% 2%,%#3 ,).%2 !1% ,!3#(%$
(%   /. 3(%  7%#43)5% 1/#%22/1 "/!1$ '%.%1!3%2 3(% !$$1%22 ,).%
).0432 9 %0%.$).' 40/. 3(% 0/2)3)/. /& ! *4-0%1 /. 3(% 
7%#43)5% 1/#%22/1 "/!1$ !$$1%22 ,).%2 9 #!. "% -%-/18 "!.+92%9
,%#3 ,).%2 /1 -)#1/01/#%22/1 !$$1%22 ,).%2
(% -%-/18 2%,%#3 #)1#4)318 01/5)$%2 ,!3#(%$ -%-/18 2%,%#3 ,).%2 !.$ !.
%.!",% 2)'.!, &/1 3(% -%-/18 $!3! "4&&%12
A18 Memory Board