Filter
Top Products
Schottky Bipolar 8214
PRIORITY INTERRUPT CONTROL UNIT
• Eight Priority Levels
• Current Status Register
• Priority Comparator
• Fully Expandable
• High Performance (50ns)
• 24-Pin Dual In-Line Package
The 8214
is
an
eight level
priority
interrupt
control
unit
designed
to
simplify
interrupt
driven microcomputer
systems.
The PICU
can
accept eight requesting levels; determine the highest
priority,
compare
this
priority
to
a soft-
ware controlled current status register and
issue
an
interrupt
to
the system along
with
vector
information
to
identify
the service routine.
The
8214
is
fully
expandable
by
the
use
of
open collector
interrupt
output
and vector
information.
Control
signals
are
also provided
to
simplify
this function.
The PICU
is
designed
to
support a wide variety
of
vectored
interrupt
structures and reduce package count
in interrupt driven microcomputer systems.
PIN
CONFIGURATION
LOGIC
DIAGRAM
[TI>
ElR
B
o
24
Vee
[}DETlG--
REQUEST
ACTIVITY
B,
2
23
ECS
l!P
R
o
(OPEN
COllECTOR)
B
2
3
22
R
7
~
R,
~
[D
ITI>
R;
SGS
4
21
R
6
~
R;
~
CD
INT
5
20
R
s
[1D
~
~
~
A
2
elK
6
19
R
4
~
~
}A
8214
INTE
18
R
3
~
~
Ao
8 17
R
2
A>B
IT>
6
0
}B
A,
9
16
R,
ED
~
A
2
10
15
R
o
[I>
S;
ED
SGS
PRIORITY
COMPARATOR
ElR
11
14 ENLG
~
ECS
GND
12
13
ETLG
PIN NAMES
IT>
INTE
------------~
[]>
ClK-------------~
INPUTS
Ro·R7
REQUEST LEVELS
(R7
HIGHEST PRIORITY)
Bo·B2
CURRENT STATUS
SGS
STATUS GROUP SELECT
ECS
ENABLE CURRENT STA"fUS
INTE INTERRUPT ENABLE
CLK CLOCK (tNT F·F)
ELR
ENABLE LEVEL READ
E1'\.G ENABLE THIS LEVELGROUP
OUTPUTS:
Ao·A2
REQUEST
LEVELS
J-
OPEN
INT
INTERRUPT (ACT.
LOW)
COLLECTOR
ENLG ENABLE NEXT LEVEL
GROUP
5-153