XR82C684CJ-F View Datasheet(PDF) - Exar Corporation
Part Name
Description
MFG CO.
'XR82C684CJ-F' PDF : 107 Pages View PDF
XR82C684
Op-Code (hex)
Mnemonic
Restart Address
(hex)
B
0
!B
!
4
0
5B
@
5
9
0
B
.
4
B
40
Table 7. 8080A and 8085 CPU Restart Instructions
Used with Vectored Interrupts
* # ' + ' ( % ' * *
% 5 (% '( %# ( 3( ,( " '(, (%
(% '( & (, + , 3(
( / % %%1 * 3 %# ,
' 3( ' / % %%1 '(
" # (* ' /5B.1 (% !
)% (, $: '&' # (% ' ' % % 3(
/ @1 ' # + 3( . (
+ , , ' 3( '
'( ( & % Table 7
Interfacing the 8080 CPU Module to the XR82C684
QUART for Interrupt Processing
00 + ' ' ' 80.0@
( $ ! ( Figure 11 % %
' ' ( ( *'(,
80.0@ 00 + * / " 1
' ( ' %%(, Please note that Figure 11
only includes information pertaining to QUART interrupt
servicing. Other circuitry (such as the 8224 Clock
Generator, the Address Bus, etc.) have been omitted from
the schematic. In this schematic, the QUART Interrupt
Service Routine is located at 002016 in memory.
Additionally, the QUART has been configured to operate
in the I-Mode. The function description of this circuit is
presented below.
80.0@ 3( I % ( 00
+# & ,, (, (% $: / 31 (% %(, (%
( ( '( (, $: ( *
+ ' 00 + % ' (% '
(% '( # ( 3( %% '( 3 $: %(, *
00 )( !( '( )% ! ( (% ( #
$: %(, * $: %(,
* 00 ' ,(' / 31 $:
$: %(, % 3 ( ,
; ' # 3 $: $: ,(' / 31#
* , 3( % ,(' / 31#
& %% (, * 5 5 (%
* :B@<@@ ! )% ** 4 (% /(,1 *
$: $: %(, % (% % (% &
( (' I %(, ( (%
' ( % % (' ,# % %( %%
$: %(, ' 5 (% * 4 %% #
# ( ( * (% (' 4 3( 3
* (% (' # !B !
(% * 00 (' Please note that, in this
example, the value “E716” is hard-wired into the input of
U3. This value is the op-code for the “RST 4” command.
Hence, once this data is gated into the CPU module, via
the data bus, the CPU will load 002016 into its Program
Counter and branch program control to that location. The
Interrupt Service Routine for the QUART exists at this
location in memory.
49
Share Link: 
