DATASHEET

82C59A FN2784
CMOS Priority Interrupt Controller Rev 6.01
Jan 22, 2020

The 82C59A is a high performance CMOS Priority Interrupt Features

Controller manufactured using an advanced 2m CMOS
process. The 82C59A is designed to relieve the system CPU • Pb-Free Plus Anneal Available (RoHS Compliant)
from the task of polling in a multilevel priority system. The • 12.5MHz, 8MHz and 5MHz Versions Available
high speed and industry standard configuration of the
• High Speed, “No Wait-State” Operation with 12.5MHz
82C59A make it compatible with microprocessors such as
80C286 and 8MHz 80C86/88
80C286, 80286, 80C86/88, 8086/88, 8080/85 and NSC800.
• Pin Compatible with NMOS 8259A
The 82C59A can handle up to eight vectored priority
interrupting sources and is cascadable to 64 without • 80C86/88/286 and 8080/85/86/88/286 Compatible
additional circuitry. Individual interrupting sources can be • Eight-Level Priority Controller, Expandable to
masked or prioritized to allow custom system configuration. 64 Levels
Two modes of operation make the 82C59A compatible with
• Programmable Interrupt Modes
both 8080/85 and 80C86/88/286 formats.
• Individual Request Mask Capability
Static CMOS circuit design ensures low operating power.
The Intersil advanced CMOS process results in performance • Fully Static Design
equal to or greater than existing equivalent products at a • Fully TTL Compatible
fraction of the power.
• Low Power Operation
- ICCSB. . . . . . . . . . . . . . . . . . . . . . . . . . 10A Maximum
- ICCOP . . . . . . . . . . . . . . . . . . . . . . 1mA/MHz Maximum
• Single 5V Power Supply
• Commercial, Industrial and Military Operating
Temperature Ranges Available

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82C59A

Ordering Information
Frequency TEMP PKG.
PART NUMBER PART MARKING (MHz) PACKAGE RANGE (°C) DWG. #

MD82C59A/7 Q 5962-95 71801VXC 5 28 Ld SBDIP (Pb-Free) -55 to +125 D28.6

5962-8501601YA 5962-8501601YA SMD# -55 to +125 F28.6

CP82C59A (No longer available, recommended CP82C59A 8 28 Ld PDIP 0 to +70 E28.6

replacement: CP82C59AZ)
CP82C59AZ (Note) CP82C59AZ 28 Ld PDIP* (Pb-Free) 0 to +70 E28.6

CS82C59AZ (Note) CS82C59AZ 28 Ld PLCC (Pb-Free) 0 to +70 N28.45

CS82C59AZ96 CS82C59AZ 28 Ld PLCC 0 to +70 N28.45

(Note) (Pb-Free, Tape & Reel)

IS82C59A (No longer available, recommended IS82C59A 28 Ld PLCC -40 to +85 N28.45
replacement: IS82C59AZ)

IS82C59AX96 No longer available, IS82C59A 28 Ld PLCC -40 to +85 N28.45

recommended replacement: IS82C59A, (Tape & Reel)
IS82C59AZX96)

IS82C59AZ IS82C59AZ 28 Ld PLCC -40 to +85 N28.45

(Note) (Pb-Free)

IS82C59AZX96 (Note) IS82C59AZ 28 Ld PLCC -40 to +85 N28.45

(Pb-Free, Tape & Reel)

ID82C59A (No longer available, recommended ID82C59A 28 Ld CERDIP -40 to +85 F28.6
replacement: IS82C59AZ)

MD82C59A/B MD82C59A/B -55 to +125 F28.6

5962-8501602YA 5962-8501602YA SMD# -55 to +125 F28.6

5962-85016023A 5962-85016023A 28 Pad CLCC - SMD# -55 to +125 J28.A

CP82C59A-12 (No longer available, CP82C59A-12 12 28 Ld PDIP 0 to +70 E28.6

recommended replacement: CS82C59A-12Z)

CP82C59A-12Z (No longer available, CP82C59A-12Z 12 28 Ld PDIP* (Pb-Free) 0 to +70 E28.6

recommended replacement: CS82C59A-12Z)
(Note)

CS82C59A-12Z (Note) CS82C59A-12Z 28 Ld PLCC (Pb-Free) 0 to +70 N28.45

CS82C59A-12Z96 (Note) CS82C59A-12Z 28 Ld PLCC (Pb-Free, 0 to +70 N28.45

Tape & Reel)

IS82C59A-12 (No longer available, IS82C59A-12 28 Ld PLCC -40 to +85 N28.45

recommended replacement: IS82C59A-12Z)

IS82C59A-12X96 (No longer available, IS82C59A-12 28 Ld PLCC -40 to +85 N28.45

recommended replacement: IS82C59A-12Z96) (Tape & Reel)

IS82C59A-12Z IS82C59A-12Z 28 Ld PLCC (Pb-Free) -40 to +85 N28.45

(Note)

IS82C59A-12Z96 IS82C59A-12Z 28 Ld PLCC -40 to +85 N28.45

(Note) (Pb-Free, Tape & Reel)
*Pb-free PDIPs can be used for through hole wave solder processing only. They are not intended for use in Reflow solder processing applications.

NOTE: Pb-free plus anneal products employ special Pb-free material sets; molding compounds/die attach materials and 100% matte tin plate
termination finish, which are RoHS compliant and compatible with both SnPb and Pb-free soldering operations. Pb-free products are MSL classified
at Pb-free peak reflow temperatures that meet or exceed the Pb-free requirements of IPC/JEDEC J STD-020.

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82C59A

Pinouts
82C59A (PDIP, CERDIP) 82C59A (PLCC, CLCC)
TOP VIEW TOP VIEW

INTA
CS 1 28 VCC

VCC
WR
RD

CS
D7

A0
WR 2 27 A0
4 3 2 1 28 27 26
RD 3 26 INTA
D6 5 25 IR7
D7 4 25 IR7
D5 6 24 IR6
D6 5 24 IR6
23 IR5 D4 7 23 IR5
D5 6
D4 7 22 IR4 D3 8 22 IR4

D3 8 21 IR3 D2 9 21 IR3
D2 9 20 IR2 D1 10 20 IR2
D1 10 19 IR1
D0 11 19 IR1
D0 11 18 IR0
12 13 14 15 16 17 18
CAS 0 12 17 INT

GND

SP/ EN

INT

IR0
CAS 0

CAS 1

CAS 2
CAS 1 13 16 SP/EN
GND 14 15 CAS 2

PIN DESCRIPTION
D7 - D0 Data Bus (Bidirectional)
RD Read Input
WR Write Input
A0 Command Select Address
CS Chip Select
CAS 2 - CAS 0 Cascade Lines
SP/EN Slave Program Input Enable
INT Interrupt Output
INTA Interrupt Acknowledge Input
IR0 - IR7 Interrupt Request Inputs

Functional Diagram
INTA INT

DATA
D7-D0 BUS
CONTROL LOGIC
BUFFER

IR0
RD READ/ IR1
WR WRITE IN - INTERRUPT IR2
A0 LOGIC SERVICE PRIORITY REQUEST IR3
REG RESOLVER REG IR4
(ISR) (IRR) IR5
CS IR6
IR7

CAS 0 CASCADE INTERRUPT MASK REG

CAS 1 BUFFER (IMR)
CAS 2 COMPARATOR

SP/EN INTERNAL BUS

FIGURE 1.

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82C59A

Pin Description
SYMBOL TYPE DESCRIPTION

VCC I VCC: The +5V power supply pin. A 0.1F capacitor between pins 28 and 14 is recommended for decoupling.

GND I GROUND

CS I CHIP SELECT: A low on this pin enables RD and WR communications between the CPU and the 82C59A. INTA
functions are independent of CS.

WR I WRITE: A low on this pin when CS is low enables the 82C59A to accept command words from the CPU.

RD I READ: A low on this pin when CS is low enables the 82C59A to release status onto the data bus for the CPU.

D7 - D0 I/O BIDIRECTIONAL DATA BUS: Control, status, and interrupt-vector information is transferred via this bus.

CAS0 - CAS2 I/O CASCADE LINES: The CAS lines form a private 82C59A bus to control a multiple 82C59A structure. These
pins are outputs for a master 82C59A and inputs for a slave 82C59A.

SP/EN I/O SLAVE PROGRAM/ENABLE BUFFER: This is a dual function pin. When in the Buffered Mode it can be used
as an output to control buffer transceivers (EN). When not in the Buffered Mode it is used as an input to
designate a master (SP = 1) or slave (SP = 0).

INT O INTERRUPT: This pin goes high whenever a valid interrupt request is asserted. It is used to interrupt the CPU,
thus, it is connected to the CPU's interrupt pin.

IR0 - IR7 I INTERRUPT REQUESTS: Asynchronous inputs. An interrupt request is executed by raising an IR input (low to
high), and holding it high until it is acknowledged (Edge Triggered Mode), or just by a high level on an IR input
(Level Triggered Mode). Internal pull-up resistors are implemented on IR0 - 7.

INTA I INTERRUPT ACKNOWLEDGE: This pin is used to enable 82C59A interrupt-vector data onto the data bus by
a sequence of interrupt acknowledge pulses issued by the CPU.

A0 I ADDRESS LINE: This pin acts in conjunction with the CS, WR, and RD pins. It is used by the 82C59A to
decipher various Command Words the CPU writes and status the CPU wishes to read. It is typically connected
to the CPU A0 address line (A1 for 80C86/88/286).

Functional Description
CPU - DRIVEN
Interrupts in Microcomputer Systems MULTIPLEXER
CPU
Microcomputer system design requires that I/O devices such
as keyboards, displays, sensors and other components
receive servicing in an efficient manner so that large
amounts of the total system tasks can be assumed by the
RAM I/O (1)
microcomputer with little or no effect on throughput.

The most common method of servicing such devices is the

Polled approach. This is where the processor must test each
device in sequence and in effect “ask” each one if it needs ROM I/O (2)

servicing. It is easy to see that a large portion of the main

program is looping through this continuous polling cycle and
that such a method would have a serious, detrimental effect
on system throughput, thus, limiting the tasks that could be I/O (N)
assumed by the microcomputer and reducing the cost
effectiveness of using such devices.
FIGURE 2. POLLED METHOD

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82C59A

A more desirable method would be one that would allow the The Programmable Interrupt Controller (PlC) functions as an
microprocessor to be executing its main program and only overall manager in an Interrupt-Driven system. It accepts
stop to service peripheral devices when it is told to do so by requests from the peripheral equipment, determines which of
the device itself. In effect, the method would provide an the incoming requests is of the highest importance (priority),
external asynchronous input that would inform the processor ascertains whether the incoming request has a higher
that it should complete whatever instruction that is currently priority value than the level currently being serviced, and
being executed and fetch a new routine that will service the issues an interrupt to the CPU based on this determination.
requesting device. Once this servicing is complete, however,
Each peripheral device or structure usually has a special
the processor would resume exactly where it left off.
program or “routine” that is associated with its specific
This is the Interrupt-driven method. It is easy to see that functional or operational requirements; this is referred to as a
system throughput would drastically increase, and thus, “service routine”. The PlC, after issuing an interrupt to the
more tasks could be assumed by the microcomputer to CPU, must somehow input information into the CPU that can
further enhance its cost effectiveness. “point” the Program Counter to the service routine
associated with the requesting device. This “pointer” is an
address in a vectoring table and will often be referred to, in
INT
this document, as vectoring data.
CPU
82C59A Functional Description
The 82C59A is a device specifically designed for use in real
PIC time, interrupt driven microcomputer systems. It manages
eight levels of requests and has built-in features for
expandability to other 82C59As (up to 64 levels). It is
programmed by system software as an I/O peripheral. A
RAM I/O (1)
selection of priority modes is available to the programmer so
that the manner in which the requests are processed by the
82C59A can be configured to match system requirements.
The priority modes can be changed or reconfigured
ROM I/O (2)
dynamically at any time during main program operation. This
means that the complete interrupt structure can be defined
as required, based on the total system environment.
I/O (N)

FIGURE 3. INTERRUPT METHOD

INTA INT

DATA
D 7 - D0 BUS
BUFFER CONTROL LOGIC

IR0
RD READ/ IR1
WR WRITE IN INTERRUPT IR2
A0 LOGIC SERVICE PRIORITY REQUEST IR3
REG RESOLVER REG IR4
(ISR) (IRR) IR5
CS IR6
IR7

CAS 0 CASCADE INTERRUPT MASK REG

CAS 1 BUFFER (IMR)
CAS 2 COMPARATOR

SP/EN INTERNAL BUS

FIGURE 4. 82C59A FUNCTIONAL DIAGRAM

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82C59A

Interrupt Request Register (IRR) and In-Service Register Read (RD)

(ISR)
A LOW on this input enables the 82C59A to send the status
The interrupts at the IR input lines are handled by two registers of the Interrupt Request Register (lRR), In-Service Register
in cascade, the Interrupt Request Register (lRR) and the In- (lSR), the Interrupt Mask Register (lMR), or the interrupt
Service Register (lSR). The IRR is used to indicate all the level (in the poll mode) onto the Data Bus.
interrupt levels which are requesting service, and the ISR is
used to store all the interrupt levels which are currently being A0
serviced. This input signal is used in conjunction with WR and RD
Priority Resolver signals to write commands into the various command
registers, as well as to read the various status registers of
This logic block determines the priorities of the bits set in the the chip. This line can be tied directly to one of the system
lRR. The highest priority is selected and strobed into the address lines.
corresponding bit of the lSR during the INTA sequence.
The Cascade Buffer/Comparator
Interrupt Mask Register (IMR)
This function block stores and compares the IDs of all
The lMR stores the bits which disable the interrupt lines to be 82C59As used in the system. The associated three I/O pins
masked. The IMR operates on the output of the IRR. (CAS0 - 2) are outputs when the 82C59A is used as a
Masking of a higher priority input will not affect the interrupt master and are inputs when the 82C59A is used as a slave.
request lines of lower priority. As a master, the 82C59A sends the ID of the interrupting
slave device onto the CAS0 - 2 lines. The slave, thus
Interrupt (INT) selected will send its preprogrammed subroutine address
This output goes directly to the CPU interrupt input. The onto the Data Bus during the next one or two consecutive
VOH level on this line is designed to be fully compatible with INTA pulses. (See section “Cascading the 82C59A”.)
the 8080, 8085, 8086/88, 80C86/88, 80286, and 80C286
input levels. Interrupt Sequence
The powerful features of the 82C59A in a microcomputer
Interrupt Acknowledge (INTA) system are its programmability and the interrupt routine
INTA pulses will cause the 82C59A to release vectoring addressing capability. The latter allows direct or indirect
information onto the data bus. The format of this data jumping to the specified interrupt routine requested without
depends on the system mode (PM) of the 82C59A. any polling of the interrupting devices. The normal sequence
of events during an interrupt depends on the type of CPU
Data Bus Buffer being used.
This 3-state, bidirectional 8-bit buffer is used to interface the
82C59A to the System Data Bus. Control words and status
information are transferred through the Data Bus Buffer.

Read/Write Control Logic

The function of this block is to accept output commands from
the CPU. It contains the Initialization Command Word (lCW)
registers and Operation Command Word (OCW) registers
which store the various control formats for device operation.
This function block also allows the status of the 82C59A to
be transferred onto the Data Bus.

Chip Select (CS)

A LOW on this input enables the 82C59A. No reading or
writing of the device will occur unless the device is selected.

Write (WR)
A LOW on this input enables the CPU to write control words
(lCWs and OCWs) to the 82C59A.

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82C59A

ADDRESS BUS (16)

CONTROL BUS

I/OR I/OW INT INTA

DATA BUS (8)

CS A0 D7 - D 0 RD WR INT INTA

CASCADE CAS 0
LINES CAS 1 82C59A
CAS 2 IRQ IRQ IRQ IRQ IRQ IRQ IRQ IRQ
SP/EN 7 6 5 4 3 2 1 0

SLAVE PROGRAM/ INTERRUPT

ENABLE BUFFER REQUESTS

FIGURE 5. 82C59A STANDARD SYSTEM BUS INTERFACE

These events occur in an 8080/8085 system: 4. The 82C59A does not drive the data bus during the first
INTA pulse.
1. One or more of the INTERRUPT REQUEST lines
(IR0 - IR7) are raised high, setting the corresponding IRR 5. The 80C86/88/286 CPU will initiate a second INTA pulse.
bit(s). During this INTA pulse, the appropriate ISR bit is set and
the corresponding bit in the IRR is reset. The 82C59A
2. The 82C59A evaluates those requests in the priority outputs the 8-bit pointer onto the data bus to be read by
resolver and sends an interrupt (INT) to the CPU, if the CPU.
appropriate.
6. This completes the interrupt cycle. In the AEOI mode, the
3. The CPU acknowledges the lNT and responds with an ISR bit is reset at the end of the second INTA pulse. Oth-
INTA pulse. erwise, the ISR bit remains set until an appropriate EOI
4. Upon receiving an lNTA from the CPU group, the highest command is issued at the end of the interrupt subroutine.
priority lSR bit is set, and the corresponding lRR bit is If no interrupt request is present at step 4 of either sequence
reset. The 82C59A will also release a CALL instruction
(i.e., the request was too short in duration), the 82C59A will
code (11001101) onto the 8-bit data bus through D0 - D7.
issue an interrupt level 7. If a slave is programmed on IR bit
5. This CALL instruction will initiate two additional INTA 7, the CAS lines remain inactive and vector addresses are
pulses to be sent to 82C59A from the CPU group. output from the master 82C59A.
6. These two INTA pulses allow the 82C59A to release its
preprogrammed subroutine address onto the data bus. Interrupt Sequence Outputs
The lower 8-bit address is released at the first INTA pulse
and the higher 8-bit address is released at the second 8080, 8085 Interrupt Response Mode
INTA pulse.
This sequence is timed by three INTA pulses. During the first
7. This completes the 3-byte CALL instruction released by lNTA pulse, the CALL opcode is enabled onto the data bus.
the 82C59A. In the AEOI mode, the lSR bit is reset at the
end of the third INTA pulse. Otherwise, the lSR bit First Interrupt Vector Byte Data: Hex CD
remains set until an appropriate EOI command is issued D7 D6 D5 D4 D3 D2 D1 D0
at the end of the interrupt sequence.
Call Code 1 1 0 0 1 1 0 1
The events occurring in an 80C86/88/286 system are the
same until step 4.
During the second INTA pulse, the lower address of the
appropriate service routine is enabled onto the data bus.

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82C59A

When interval = 4 bits, A5 - A7 are programmed, while slave if so programmed) will send a byte of data to the
A0 - A4 are automatically inserted by the 82C59A. When processor with the acknowledged interrupt code composed
interval = 8, only A6 and A7 are programmed, while A0 - A5 as follows (note the state of the ADI mode control is ignored
are automatically inserted. and A5 - A11 are unused in the 86/88/286 mode).

CONTENT OF INTERRUPT VECTOR BYTE FOR

CONTENT OF SECOND INTERRUPT VECTOR BYTE 80C86/88/286 SYSTEM MODE
IR INTERVAL = 4 D7 D6 D5 D4 D3 D2 D1 D0
D7 D6 D5 D4 D3 D2 D1 D0 lR7 T7 T6 T5 T4 T3 1 1 1
7 A7 A6 A5 1 1 1 0 0 lR6 T7 T6 T5 T4 T3 1 1 0
6 A7 A6 A5 1 1 0 0 0 IR5 T7 T6 T5 T4 T3 1 0 1
5 A7 A6 A5 1 0 1 0 0 IR4 T7 T6 T5 T4 T3 1 0 0
4 A7 A6 A5 1 0 0 0 0 IR3 T7 T6 T5 T4 T3 0 1 1
3 A7 A6 A5 0 1 1 0 0 IR2 T7 T6 T5 T4 T3 0 1 0
2 A7 A6 A5 0 1 0 0 0 IR1 T7 T6 T5 T4 T3 0 0 1
1 A7 A6 A5 0 0 1 0 0 IR0 T7 T6 T5 T4 T3 0 0 0
0 A7 A6 A5 0 0 0 0 0
Programming the 82C59A

IR INTERVAL = 8 The 82C59A accepts two types of command words

generated by the CPU:
D7 D6 DS D4 D3 D2 D1 D0

7 A7 A6 1 1 1 0 0 0
1. Initialization Command Words (ICWs): Before normal
operation can begin, each 82C59A in the system must be
6 A7 A6 1 1 0 0 0 0 brought to a starting point - by a sequence of 2 to 4 bytes
5 A7 A6 1 0 1 0 0 0 timed by WR pulses.

4 A7 A6 1 0 0 0 0 0 2. Operation Command Words (OCWs): These are the

command words which command the 82C59A to operate
3 A7 A6 0 1 1 0 0 0 in various interrupt modes. Among these modes are:
2 A7 A6 0 1 0 0 0 0
a. Fully nested mode.
1 A7 A6 0 0 1 0 0 0
b. Rotating priority mode.
0 A7 A6 0 0 0 0 0 0
c. Special mask mode.

During the third INTA pulse, the higher address of the d. Polled mode.
appropriate service routine, which was programmed as byte 2 The OCWs can be written into the 82C59A anytime after
of the initialization sequence (A8 - A15), is enabled onto the initialization.
bus.
Initialization Command Words (lCWs)
CONTENT OF THIRD INTERRUPT VECTOR BYTE

D7 D6 D5 D4 D3 D2 D1 D0 General
A15 A14 A13 A12 A11 A10 A9 A8 Whenever a command is issued with A0 = 0 and D4 = 1, this
is interpreted as Initialization Command Word 1 (lCW1).
80C86, 8OC88, 80C286 Interrupt Response Mode
lCW1 starts the initialization sequence during which the
80C86/88/286 mode is similar to 8080/85 mode except that following automatically occur:
only two Interrupt Acknowledge cycles are issued by the
a. The edge sense circuit is reset, which means that follow-
processor and no CALL opcode is sent to the processor. The
ing initialization, an interrupt request (IR) input must make
first interrupt acknowledge cycle is similar to that of 8080/85 a low-to-high transition to generate an interrupt.
systems in that the 82C59A uses it to internally freeze the
state of the interrupts for priority resolution and, as a master, b. The Interrupt Mask Register is cleared.
it issues the interrupt code on the cascade lines. On this first c. lR7 input is assigned priority 7.
cycle, it does not issue any data to the processor and leaves
d. Special Mask Mode is cleared and Status Read is set to
its data bus buffers disabled. On the second interrupt
lRR.
acknowledge cycle in the 86/88/286 mode, the master (or

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82C59A

e. If lC4 = 0, then all functions selected in lCW4 are set to LTlM: If LTlM = 1, then the 82C59A will operate in the level
zero. (Non-Buffered mode (see note), no Auto-EOI, 8080/85 interrupt mode. Edge detect logic on the interrupt
system). inputs will be disabled.
NOTE: Master/Slave in ICW4 is only used in the buffered mode. ADI: ALL address interval. ADI = 1 then interval = 4; ADI =
0 then interval = 8.
SNGL: Single. Means that this is the only 82C59A in the sys-
ICW1
tem. If SNGL = 1, no ICW3 will be issued.
IC4: If this bit is set - lCW4 has to be issued. If lCW4 is not
ICW2
needed, set lC4 = 0.

Initialization Command Word 3 (ICW3)

This word is read only when there is more than one 82C59A in
NO (SNGL = 1) IN the system and cascading is used, in which case
CASCADE
MODE SNGL = 0. It will load the 8-bit slave register. The functions of
this register are:
YES (SNGL = 0))
a. In the master mode (either when SP = 1, or in buffered
ICW3 mode when M/S = 1 in lCW4) a “1” is set for each slave in
the bit corresponding to the appropriate IR line for the slave.
The master then will release byte 1 of the call sequence (for
8080/85 system) and will enable the corresponding slave to
NO (IC4 = 0)
IS ICW4
release bytes 2 and 3 (for 80C86/88/ 286, only byte 2)
NEEDED through the cascade lines.
b. In the slave mode (either when SP = 0, or if BUF = 1 and M/S
YES (IC4 = 1) = 0 in lCW4), bits 2 - 0 identify the slave. The slave compares
its cascade input with these bits and if they are equal, bytes 2
ICW4 and 3 of the call sequence (or just byte 2 for 80C86/88/286)
are released by it on the Data Bus.
NOTE: (The slave address must correspond to the IR line it is
READY TO ACCEPT
INTERRUPT REQUESTS connected to in the master ID).

Initialization Command Word 4 (ICW4)

FIGURE 6. 82C59A INITIALIZATION SEQUENCE
SFNM: If SFNM = 1, the special fully nested mode is pro-
Initialization Command Words 1 and 2 (ICW1, lCW2) grammed.

A5 - A15: Page starting address of service routines. In an BUF: If BUF = 1, the buffered mode is programmed. In buff-
ered mode, SP/EN becomes an enable output and
8080/85 system the 8 request levels will generate CALLS to 8
the master/slave determination is by M/S.
locations equally spaced in memory. These can be
programmed to be spaced at intervals of 4 or 8 memory M/S: If buffered mode is selected: M/S = 1 means the
locations, thus, the 8 routines will occupy a page of 32 or 64 82C59A is programmed to be a master, M/S = 0
bytes, respectively. means the 82C59A is programmed to be a slave. If
BUF = 0, M/S has no function.
The address format is 2 bytes long (A0 - A15). When the
AEOI: If AEOI = 1, the automatic end of interrupt mode is pro-
routine interval is 4, A0 - A4 are automatically inserted by the
grammed.
82C59A, while A5 - A15 are programmed externally. When the
routine interval is 8, A0 - A5 are automatically inserted by the PM: Microprocessor mode: PM = 0 sets the 82C59A for
82C59A while A6 - A15 are programmed externally. 8080/85 system operation, PM = 1 sets the 82C59A
for 80C86/88/286 system operation.
The 8-byte interval will maintain compatibility with current
software, while the 4-byte interval is best for a compact jump
table.
In an 80C86/88/286 system, A15 - A11 are inserted in the five
most significant bits of the vectoring byte and the 82C59A sets
the three least significant bits according to the interrupt level.
A10 - A5 are ignored and ADI (Address interval) has no effect.

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82C59A

ICW1

A0 D7 D6 D5 D4 D3 D2 D1 D0
0 A7 A6 A5 1 LTIM ADI SNGL IC4

1 = ICW4 needed
0 = No ICW4 needed

1 = Single
0 = Cascade Mode

CALL address interval

1 = Interval of 4
0 = Interval of 8

1 = Level triggered mode

0 = Edge triggered mode
A7 - A5 of Interrupt vector address
(MCS-80/85 mode only)
ICW2

A0 D7 D6 D5 D4 D3 D2 D1 D0
A15 A14 A13 A12 A11 A10 A9 A8
1
T7 T6 T5 T4 T3

A15 - A8 of interrupt vector address

(MCS80/85 mode)
T7 - T3 of interrupt vector address
(8086/8088 mode)
ICW3 (MASTER DEVICE)

A0 D7 D6 D5 D4 D3 D2 D1 D0
1 S7 S6 S5 S4 S3 S2 S1 S0

1 = IR input has a slave

0 = IR input does not have a slave
ICW3 (SLAVE DEVICE)

A0 D7 D6 D5 D4 D3 D2 D1 D0
1 0 0 0 0 0 ID2 ID1 ID0
SLAVE ID (NOTE)

0 1 2 3 4 5 6 7
0 1 0 1 0 1 0 1
0 0 1 1 0 0 1 1
0 0 0 0 1 1 1 1

ICW4

A0 D7 D6 D5 D4 D3 D2 D1 D0
1 0 0 0 SFNM BUF M/S AEOI PM

1 = 8086/8088 mode
0 = MCS-80/85 mode
1 = Auto EOI
0 = Normal EOI
0 X - Non buffered mode

1 0 - Buffered mode slave

1 1 - Buffered mode master

1 = Special fully nested moded

0 = Not special fully nested mode
NOTE: Slave ID is equal to the corresponding master IR input.

FIGURE 7. 82C59A INITIALIZATION COMMAND WORD FORMAT

FN2784 Rev 6.01 Page 10 of 24

Jan 22, 2020
82C59A

Operation Command Words (OCWs) trailing edge of the last INTA. While the IS bit is set, all
further interrupts of the same or lower priority are inhibited,
After the Initialization Command Words (lCWs) are while higher levels will generate an interrupt (which will be
programmed into the 82C59A, the device is ready to accept acknowledged only if the microprocessor internal interrupt
interrupt requests at its input lines. However, during the enable flip-flop has been re-enabled through software).
82C59A operation, a selection of algorithms can command
the 82C59A to operate in various modes through the After the initialization sequence, IR0 has the highest priority
Operation Command Words (OCWs). and IR7 the lowest. Priorities can be changed, as will be
explained in the rotating priority mode or via the set priority
OPERATION COMMAND WORDS (OCWs)
command.
A0 D7 D6 D5 D4 D3 D2 D1 D0

OCW1

1 M7 M6 M5 M4 M3 M2 M1 M0

OCW2

0 R SL EOI 0 0 L2 L1 L0

OCW3

0 0 ESMM SMM 0 1 P RR RIS

Operation Command Word 1 (OCW1)

OCW1 sets and clears the mask bits in the Interrupt Mask
Register (lMR) M7 - M0 represent the eight mask bits. M = 1
indicates the channel is masked (inhibited), M = 0 indicates
the channel is enabled.

Operation Command Word 2 (OCW2)

R, SL, EOI - These three bits control the Rotate and End of
Interrupt modes and combinations of the two. A chart of
these combinations can be found on the Operation
Command Word Format.

L2, L1, L0 - These bits determine the interrupt level acted

upon when the SL bit is active.

Operation Command Word 3 (OCW3)

ESMM - Enable Special Mask Mode. When this bit is set to 1
it enables the SMM bit to set or reset the Special Mask
Mode. When ESMM = 0, the SMM bit becomes a “don’t
care”.

SMM - Special Mask Mode. If ESMM = 1 and SMM = 1, the

82C59A will enter Special Mask Mode. If ESMM = 1 and
SMM = 0, the 82C59A will revert to normal mask mode.
When ESMM = 0, SMM has no effect.

Fully Nested Mode

This mode is entered after initialization unless another mode
is programmed. The interrupt requests are ordered in priority
from 0 through 7 (0 highest). When an interrupt is
acknowledged the highest priority request is determined and
its vector placed on the bus. Additionally, a bit of the Interrupt
Service register (IS0 - 7) is set. This bit remains set until the
microprocessor issues an End of Interrupt (EOI) command
immediately before returning from the service routine, or if
the AEOI (Automatic End of Interrupt) bit is set, until the

FN2784 Rev 6.01 Page 11 of 24

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82C59A

OCW1

A0 D7 D6 D5 D4 D3 D2 D1 D0
1 M7 M6 M5 M4 M3 M2 M1 M0

Interrupt Mask
1 = Mask set
0 = Mask reset
OCW2

A0 D7 D6 D5 D4 D3 D2 D1 D0
0 R SL EOI 0 0 L2 L1 L0 IR LEVEL TO BE
ACTED UPON
0 1 2 3 4 5 6 7
0 1 0 1 0 1 0 1
0 0 1 1 0 0 1 1
0 0 1 Non-specific EOI command 0 0 0 0 1 1 1 1
End of interrupt
0 1 1 † Specific EOI command
1 0 1 Rotate on non-specific EOI command
1 0 0 Rotate in automatic EOI mode (set)
0 0 0 Automatic rotation
Rotate in automatic EOI mode (clear)
1 1 1 † Rotate on specific EOI command
1 1 0 † Set priority command
Specific rotation
0 1 0 No operation
† L0 - L2 are used
OCW3

A0 D7 D6 D5 D4 D3 D2 D1 D0
0 0 ESMM SMM 0 1 P RR RIS
READ REGISTER COMMAND
0 1 0 1
0 0 1 1

Read IR reg on Read IS reg on

No Action next RD pulse next RD pulse

1 = Poll command
0 = No poll command
SPECIAL MASK MODE
0 1 0 1
0 0 1 1

Reset special Set special

No Action mask mask

FIGURE 8. 82C59A OPERATION COMMAND WORD FORMAT

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82C59A

End of Interrupt (EOI)

The In-Service (IS) bit can be reset either automatically IS7 IS6 IS5 IS4 IS3 IS2 IS1 IS0
following the trailing edge of the last in sequence INTA pulse “IS” Status 0 1 0 1 0 0 0 0
(when AEOI bit in lCW1 is set) or by a command word that
Priority 7 6 5 4 3 2 1 0
must be issued to the 82C59A before returning from a Status
service routine (EOI Command). An EOI command must be
issued twice if servicing a slave in the Cascade mode, once lowest highest
for the master and once for the corresponding slave.
After Rotate (lR4 was serviced, all other priorities rotated
There are two forms of EOl command: Specific and Non-
correspondingly)
Specific. When the 82C59A is operated in modes which
preserve the fully nested structure, it can determine which IS
IS7 IS6 IS5 IS4 IS3 IS2 IS1 IS0
bit to reset on EOI. When a Non-Specific command is issued
the 82C59A will automatically reset the highest IS bit of “IS” Status 0 1 0 0 0 0 0 0
those that are set, since in the fully nested mode the highest Priority 2 1 0 7 6 5 4 3
IS level was necessarily the last level acknowledged and Status
serviced. A non-specific EOI can be issued with OCW2
highest lowest
(EOl = 1, SL = 0, R = 0).

When a mode is used which may disturb the fully nested There are two ways to accomplish Automatic Rotation using
structure, the 82C59A may no longer be able to determine OCW2, the Rotation on Non-Specific EOI Command (R = 1,
the last level acknowledged. In this case a Specific End of SL = 0, EOI = 1) and the Rotate in Automatic EOI Mode
Interrupt must be issued which includes as part of the which is set by (R = 1, SL = 0, EOI = 0) and cleared by
command the IS level to be reset. A specific EOl can be (R = 0, SL = 0, EOl = 0).
issued with OCW2 (EOI = 1, SL = 1, R = 0, and L0 - L2 is the
binary level of the IS bit to be reset). Specific Rotation (Specific Priority)

An lRR bit that is masked by an lMR bit will not be cleared by The programmer can change priorities by programming the
a non-specific EOI if the 82C59A is in the Special Mask lowest priority and thus, fixing all other priorities; i.e., if IR5 is
Mode. programmed as the lowest priority device, then IR6 will have
the highest one.
Automatic End of Interrupt (AEOI) Mode
The Set Priority command is issued in OCW2 where: R = 1,
If AEOI = 1 in lCW4, then the 82C59A will operate in AEOl SL = 1, L0 - L2 is the binary priority level code of the lowest
mode continuously until reprogrammed by lCW4. In this priority device.
mode the 82C59A will automatically perform a non-specific
EOI operation at the trailing edge of the last interrupt Observe that in this mode internal status is updated by soft-
acknowledge pulse (third pulse in 8080/85, second in ware control during OCW2. However, it is independent of the
80C86/88/286). Note that from a system standpoint, this End of Interrupt (EOI) command (also executed by OCW2).
mode should be used only when a nested multilevel interrupt Priority changes can be executed during an EOI command
structure is not required within a single 82C59A. by using the Rotate on Specific EOl command in OCW2
(R = 1, SL = 1, EOI = 1, and L0 - L2 = IR level to receive
Automatic Rotation (Equal Priority Devices) lowest priority).

In some applications there are a number of interrupting Interrupt Masks

devices of equal priority. In this mode a device, after being
serviced, receives the lowest priority, so a device requesting Each Interrupt Request input can be masked individually by
an interrupt will have to wait, in the worst case until each of 7 the Interrupt Mask Register (IMR) programmed through
other devices are serviced at most once. For example, if the OCW1. Each bit in the lMR masks one interrupt channel if it
priority and “in service” status is: is set (1). Bit 0 masks IR0, Bit 1 masks IR1 and so forth.
Masking an IR channel does not affect the operation of other
Before Rotate (lR4 the highest priority requiring service) channels.

Special Mask Mode

Some applications may require an interrupt service routine
to dynamically alter the system priority structure during its
execution under software control. For example, the routine
may wish to inhibit lower priority requests for a portion of its
execution but enable some of them for another portion.

FN2784 Rev 6.01 Page 13 of 24

Jan 22, 2020
82C59A

The difficulty here is that if an Interrupt Request is disabling its interrupt input. Service to devices is achieved by
acknowledged and an End of Interrupt command did not software using a Poll command.
reset its IS bit (i.e., while executing a service routine), the
The Poll command is issued by setting P = 1 in OCW3. The
82C59A would have inhibited all lower priority requests with
82C59A treats the next RD pulse to the 82C59A (i.e., RD =
no easy way for the routine to enable them.
0, CS = 0) as an interrupt acknowledge, sets the appropriate
That is where the Special Mask Mode comes in. In the IS bit if there is a request, and reads the priority level.
Special Mask Mode, when a mask bit is set in OCW1, it Interrupt is frozen from WR to RD.
inhibits further interrupts at that level and enables interrupts
The word enabled onto the data bus during RD is:
from all other levels (lower as well as higher) that are not
masked. D7 D6 D5 D4 D3 D2 D1 D0
Thus, any interrupts may be selectively enabled by loading I - - - - W2 W1 W0
the mask register.

The Special Mask Mode is set by OCW3 where: ESMM = 1, W0 - W2: Binary code of the highest priority level request-
SMM = 1, and cleared where ESMM = 1, SMM = 0. ing service.
I: Equal to a “1” if there is an interrupt.
Poll Command
This mode is useful if there is a routine command common to
In this mode, the INT output is not used or the
several levels so that the INTA sequence is not needed
microprocessor internal Interrupt Enable flip flop is reset,
(saves ROM space). Another application is to use the poll
mode to expand the number of priority levels to more than 64.

LTIM BIT TO OTHER PRIORITY CELLS

0 = EDGE
1 = LEVEL
CLR ISR
EDGE
SENSE CLR
LATCH Q ISR BIT
PRIORITY
SET RESOLVER
CLR
VCC Q SET ISR
SET IN - SERVICE
LATCH
REQUEST CONTROL
LATCH LOGIC

D Q NON-
IR MASK LATCH MASKED
C Q REQ
D Q
INTA
C
8080/85
MODE CLR
FREEZE

80C86/ INTA READ IMR

88/286 READ ISR
FREEZE READ WRITE MASTER CLEAR
MODE FREEZE IRR MASK

NOTES:
1. Master clear active only during ICW1.
2. FREEZE is active during INTA and poll sequence only.
3. Truth Table for D-latch.

C D Q Operation

1 D1 D1 Follow

0 X Qn-1 Hold

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82C59A

Reading the 82C59A Status Edge and Level Triggered Modes

The input status of several internal registers can be read to This mode is programmed using bit 3 in lCW1.
update the user information on the system. The following
If LTlM = “0”, an interrupt request will be recognized by a low to
registers can be read via OCW3 (lRR and ISR) or OCW1
high transition on an IR input. The IR input can remain high
(lMR).
without generating another interrupt.
Interrupt Request Register (IRR): 8-bit register which
If LTIM = “1”, an interrupt request will be recognized by a “high”
contains the levels requesting an interrupt to be
level on an IR input, and there is no need for an edge detection.
acknowledged. The highest request level is reset from the
The interrupt request must be removed before the EOI
lRR when an interrupt is acknowledged. lRR is not affected
command is issued or the CPU interrupt is enabled to prevent a
by lMR.
second interrupt from occurring.
In-Service Register (ISR): 8-bit register which contains the
The priority cell diagram shows a conceptual circuit of the level
priority levels that are being serviced. The ISR is updated
sensitive and edge sensitive input circuitry of the 82C59A. Be
when an End of Interrupt Command is issued.
sure to note that the request latch is a transparent D type latch.
Interrupt Mask Register: 8-bit register which contains the
In both the edge and level triggered modes the IR inputs
interrupt request lines which are masked.
must remain high until after the falling edge of the first INTA.
The lRR can be read when, prior to the RD pulse, a Read If the IR input goes low before this time a DEFAULT lR7 will
Register Command is issued with OCW3 (RR = 1, RIS = 0). occur when the CPU acknowledges the interrupt. This can
be a useful safeguard for detecting interrupts caused by
The ISR can be read when, prior to the RD pulse, a Read
spurious noise glitches on the IR inputs. To implement this
Register Command is issued with OCW3 (RR = 1, RIS = 1).
feature the lR7 routine is used for “clean up” simply
There is no need to write an OCW3 before every status read executing a return instruction, thus, ignoring the interrupt. If
operation, as long as the status read corresponds with the lR7 is needed for other purposes a default lR7 can still be
previous one: i.e., the 82C59A “remembers” whether the lRR detected by reading the ISR. A normal lR7 interrupt will set
or ISR has been previously selected by the OCW3. This is the corresponding ISR bit, a default IR7 won’t. If a default
not true when poll is used. In the poll mode, the 82C59A IR7 routine occurs during a normal lR7 routine, however, the
treats the RD following a “poll write” operation as an INTA. ISR will remain set. In this case it is necessary to keep track
After initialization, the 82C59A is set to lRR. of whether or not the IR7 routine was previously entered. If
another lR7 occurs it is a default.
For reading the lMR, no OCW3 is needed. The output data bus
will contain the lMR whenever RD is active and A0 = 1 (OCW1). In power sensitive applications, it is advisable to place the
Polling overrides status read when P = 1, RR = 1 in OCW3. 82C59A in the edge-triggered mode with the IR lines
normally high. This will minimize the current through the
internal pull-up resistors on the IR pins.

80C86/88/286
8080/85
IR

INT
80C86/88/286

INTA

LATCH LATCH 8080/85 LATCH

ARM ARM ARM
(NOTE 1) (NOTE 1) (NOTE 1)
EARLIEST IR
CAN BE
REMOVED

NOTE:
1. Edge triggered mode only.
FIGURE 10. IR TRIGGERING TIMING REQUIREMENTS

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82C59A

The Special Fully Nested Mode This modification forces the use of software programming to
determine whether the 82C59A is a master or a slave. Bit 3
This mode will be used in the case of a big system where
in ICW4 programs the buffered mode, and bit 2 in lCW4
cascading is used, and the priority has to be conserved
determines whether it is a master or a slave.
within each slave. In this case the special fully nested mode
will be programmed to the master (using lCW4). This mode Cascade Mode
is similar to the normal nested mode with the following
exceptions: The 82C59A can be easily interconnected in a system of one
master with up to eight slaves to handle up to 64 priority
a. When an interrupt request from a certain slave is in ser- levels.
vice, this slave is not locked out from the master’s priority
logic and further interrupt requests from higher priority The master controls the slaves through the 3 line cascade
IRs within the slave will be recognized by the master and bus (CAS2 - 0). The cascade bus acts like chip selects to the
will initiate interrupts to the processor. (In the normal slaves during the INTA sequence.
nested mode a slave is masked out when its request is in
In a cascade configuration, the slave interrupt outputs (INT)
service and no higher requests from the same slave can
are connected to the master interrupt request inputs. When a
be serviced.
slave request line is activated and afterwards acknowledged,
b. When exiting the Interrupt Service routine the software the master will enable the corresponding slave to release the
has to check whether the interrupt serviced was the only device routine address during bytes 2 and 3 of INTA. (Byte 2
one from that slave. This is done by sending a non-spe- only for 80C86/88/286).
cific End of Interrupt (EOI) command to the slave and
then reading its In-Service register and checking for zero. The cascade bus lines are normally low and will contain the
If it is empty, a non-specified EOI can be sent to the mas- slave address code from the leading edge of the first INTA
ter, too. If not, no EOI should be sent. pulse to the trailing edge of the last INTA pulse. Each
82C59A in the system must follow a separate initialization
Buffered Mode
sequence and can be programmed to work in a different
When the 82C59A is used in a large system where bus mode. An EOI command must be issued twice: once for the
driving buffers are required on the data bus and the master and once for the corresponding slave. Chip select
cascading mode is used, there exists the problem of decoding is required to activate each 82C59A.
enabling buffers NOTE: Auto EOI is supported in the slave mode for the 82C59A.
The buffered mode will structure the 82C59A to send an The cascade lines of the Master 82C59A are activated only
enable signal on SP/EN to enable the buffers. In this mode, for slave inputs, non-slave inputs leave the cascade line
whenever the 82C59A’s data bus outputs are enabled, the inactive (low). Therefore, it is necessary to use a slave
SP/EN output becomes active. address of 0 (zero) only after all other addresses are used.

ADDRESS BUS (16)

CONTROL BUS
INT REQ
DATA BUS (8)

CS A0 D7 - D0 INTA INT CS A0 D7 - D0 INTA INT CS A0 D7 - D0 INTA INT

CAS 0 CAS 0 CAS 0
82C59A SLAVE A CAS 1 82C59A SLAVE B CAS 1 CAS 1 MASTER 82C59A
CAS 2 CAS 2 CAS 2
SP/EN 7 6 5 4 3 2 1 0 SP/EN 7 6 5 4 3 2 1 0 SP/EN 7 6 5 4 3 2 1 0

GND 7 6 5 4 3 2 1 0 GND 7 6 5 4 3 2 1 0 VCC 7 6 5 4 3 2 1 0

INTERRUPT REQUESTS

FIGURE 11. CASCADING THE 82C59A

FN2784 Rev 6.01 Page 16 of 24

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82C59A

Absolute Maximum Ratings Thermal Information

Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +8.0V Thermal Resistance (Typical) JA (°C/W) JC (°C/W)
Input, Output or I/O Voltage . . . . . . . . . . . . . GND-0.5V to VCC+0.5V CERDIP Package. . . . . . . . . . . . . . . . . 55 12
ESD Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Class I CLCC Package . . . . . . . . . . . . . . . . . . 65 14
PDIP Package* . . . . . . . . . . . . . . . . . . 55 N/A
Operating Conditions PLCC Package. . . . . . . . . . . . . . . . . . . 65 N/A
Storage Temperature Range . . . . . . . . . . . . . . . . . . -65°C to +150°C
Operating Voltage Range. . . . . . . . . . . . . . . . . . . . . . +4.5V to +5.5V
Maximum Junction Temperature Ceramic Package . . . . . . . +175°C
Operating Temperature Range
CX82C59A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0oC to 70oC Maximum Junction Temperature Plastic Package . . . . . . . . . +150°C
Maximum Lead Temperature Package (Soldering 10s). . . . . +300°C
IX82C59A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -40oC to 85oC
(PLCC - Lead Tips Only)
MX82C59A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55oC to 125oC
Input Low Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0V to +0.8V *Pb-free PDIPs can be used for through hole wave solder processing
only. They are not intended for use in Reflow solder processing
applications.

Die Characteristics
Gate Count . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1250 Gates
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.

DC Electrical Specifications VCC = +5.0V 10%, TA = Operating Temperature Range

SYMBOL PARAMETER MIN MAX UNITS TEST CONDITIONS

VlH Logical One Input Voltage 2.0 - V C82C59A, I82C59A
2.2 V M82C59A
VIL Logical Zero Input Voltage - 0.8 V
VOH Output HIGH Voltage 3.0 - V IOH = -2.5mA
VCC -0.4 V lOH = -100A
VOL Output LOW Voltage - 0.4 V lOL = +2.5mA
II Input Leakage Current -1.0 +1.0 A VIN = GND or VCC, Pins 1-3, 26-27
IO Output Leakage Current -10.0 +10.0 A VOUT = GND or VCC, Pins 4-13, 15-16
ILIR IR Input Load Current - -200 A VIN = 0V
- 10 A VIN = VCC
lCCSB Standby Power Supply Current - 10 A VCC = 5.5V, VIN = VCC or GND Outputs
Open, (Note 1)
ICCOP Operating Power Supply Current - 1 mA/MHz VCC = 5.0V, VIN = VCC or GND, Outputs Open,
TA = 25°C, (Note 2)
NOTES:
1. Except for IR0 - lR7 where VIN = VCC or open.
2. ICCOP = 1mA/MHz of peripheral read/write cycle time. (ex: 1.0s I/O read/write cycle time = 1mA).

Capacitance TA = +25°C
SYMBOL PARAMETER TYP UNITS TEST CONDITIONS
CIN Input Capacitance 15 pF FREQ = 1MHz, all measurements reference to
device GND.
COUT Output Capacitance 15 pF
CI/O I/O Capacitance 15 pF

AC Electrical Specifications VCC = +5.0V 10%, GND = 0V, TA = Operating Temperature Range

5MHz 8MHz 12.5MHz

TEST
SYMBOL PARAMETER MIN MAX MIN MAX MIN MAX UNITS CONDITIONS
TIMING REQUIREMENTS
(1) TAHRL A0/CS Setup to RD/INTA 10 - 10 - 5 - ns
(2) TRHAX A0/CS Hold after RD/INTA 5 - 5 - 0 - ns
(3) TRLRH RD/lNTA Pulse Width 235 - 160 - 60 - ns

FN2784 Rev 6.01 Page 17 of 24

Jan 22, 2020
82C59A

AC Electrical Specifications VCC = +5.0V 10%, GND = 0V, TA = Operating Temperature Range (Continued)

5MHz 8MHz 12.5MHz

TEST
SYMBOL PARAMETER MIN MAX MIN MAX MIN MAX UNITS CONDITIONS
(4) TAHWL A0/CS Setup to WR 0 - 0 - 0 - ns
(5) TWHAX A0/CS Hold after WR 5 - 5 - 0 - ns
(6) TWLWH WR Pulse Width 165 - 95 - 60 - ns
(7) TDVWH Data Setup to WR 240 - 160 - 70 - ns
(8) TWHDX Data Hold after WR 5 - 5 - 0 - ns
(9) TJLJH Interrupt Request Width Low 100 - 100 - 40 - ns
(10) TCVlAL Cascade Setup to Second or Third INTA (Slave 55 - 40 - 30 - ns
Only)
(11) TRHRL End of RD to next RD, End of INTA (within an 160 - 160 - 90 - ns
INTA sequence only)
(12) TWHWL End of WR to next WR 190 - 190 - 60 - ns
(13) TCHCL End of Command to next command (not same 500 - 400 - 90 - ns
(Note 1) command type), End of INTA
sequence to next INTA sequence
TIMING RESPONSES
(14) TRLDV Data Valid from RD/INTA - 160 - 120 - 40 ns 1
(15) TRHDZ Data Float after RD/INTA 5 100 5 85 5 22 ns 2
(16) TJHlH Interrupt Output Delay - 350 - 300 - 90 ns 1
(17) TlALCV Cascade Valid from First INTA - 565 - 360 - 50 ns 1
(Master Only)
(18) TRLEL Enable Active from RD or INTA - 125 - 100 - 40 ns 1
(19) TRHEH Enable Inactive from RD or INTA - 60 - 50 - 22 ns 1
(20) TAHDV Data Valid from Stable Address - 210 - 200 - 60 ns 1
(21) TCVDV Cascade Valid to Valid Data - 300 - 200 - 70 ns 1
NOTE:
1. Worst case timing for TCHCL in an actual microprocessor system is typically greater than the values specified for the 82C59A,
(i.e. 8085A = 1.6s, 8085A -2 = 1s, 80C86 = 1s, 80C286 -10 = 131ns, 80C286 -12 = 98ns).

AC Test Circuit
V1

R1
OUTPUT FROM TEST
DEVICE UNDER POINT
TEST C1 R2
(NOTE)

NOTE: Includes stray and jig capacitance.

TEST CONDITION DEFINITION TABLE

TEST
CONDITION V1 R1 R2 C1

1 1.7V 523 Open 100pF

2 VCC 1.8k 1.8k 50pF

FN2784 Rev 6.01 Page 18 of 24

Jan 22, 2020
82C59A

AC Testing Input, Output Waveform

INPUT OUTPUT
VIH +0.4V VOH

1.5V 1.5V

VIL - 0.4V VOL

NOTE: AC Testing: All input signals must switch between VIL - 0.4V and VIH + 0.4V. Input rise and fall times are driven at 1ns/V.

Timing Waveforms

WR (6)
TWLWH

(4) (5)
TAHWL TWHAX
CS
ADDRESS BUS
A0
(7) (8)
TDVWH TWHDX

DATA BUS

FIGURE 12. WRITE

(3)
RD/INTA TRLRH

(18) (19)
TRLEL TRHEH
EN

(1) (2)
TAHRL TRHAX
CS
ADDRESS BUS
A0
(14) (15)
TRLDV TRHDZ

DATA BUS
(20)
TAHDV

FIGURE 13. READ/INTA

RD
INTA (11)
TRHRL

WR
(12)
RD TWHWL
INTA
WR (13)
TCHCL
RD
INTA
WR

FIGURE 14. OTHER TIMING

FN2784 Rev 6.01 Page 19 of 24

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82C59A

Timing Waveforms (Continued)

(16)
TJHIH
IR

(9) SEE NOTE 3 SEE NOTE 4

TJLJH

INT

INTA
SEE NOTE 1

SEE
DB NOTE 2
(10) (10)
TCVIAL TCVIAL

CAS 0 - 2
(17) (21)
TIALCV TCVDV

NOTES:
1. Interrupt Request (IR) must remain HIGH until leading edge of first INTA.
2. During first INTA the Data Bus is not active in 80C86/88/286 mode.
3. 80C86/88/286 mode.
4. 8080/8085 mode.
FIGURE 15. INTA SEQUENCE

Burn-In Circuits
MD82C59A CERDIP

R1
GND 1 28 VCC
R1
WR 2 27 R1 A0 C1
R1
RD 3 26 R1 INTA
R1
D7 4 25 R2 IR7
R1
D6 5 24 R2 IR6 VCC
R1
D5 6 23 R2 IR5
R1
D4 7 22 R2 IR4
R1 R3
D3 8 21 R2 IR3
R1 A
D2 9 20 R2 IR2
R1
D1 10 19 R2 IR1
R3
R1
D0 11 18 R2 IR0
R3
CAS 0 12 17 A
R3
CAS 1 13 16 R3 SP/EN

GND 14 15 R3 CAS 2

FN2784 Rev 6.01 Page 20 of 24

Jan 22, 2020
82C59A

Burn-In Circuits
5962-850160X3A CLCC

VCC C1

D7 RD WR GND A0 INTA
R1 R1 R1 R1 R1 R1

4 3 2 1 28 27 26
R1 R2
D6 5 25 IR7
R1 R2
D5 6 24 IR6
R1 R2
D4 7 23 IR5
R1 R2
D3 8 22 IR4
R1 R2
D2 9 21 IR3
R1 R2
D1 10 20 IR2
R1 R2
D0 11 19 IR1
12 13 14 15 16 17 18

R1 R1 R1 R1 R4 R2

IR0
GND

SP/EN
CAS0

CAS1

CAS2

VCC/2

NOTES:
1. VCC = 5.5V 0.5V. 7. R3 = 10k 5%.
2. VIH = 4.5V 10%. 8. R4 = 1.2k 5%.
3. VIL = -0.2V to 0.4V. 9. C1 = 0.01F min.
4. GND = 0V. 10. F0 = 100kHz 10%.
5. R1 = 47k 5%. 11. F1 = F0/2, F2 = F1/2, ...F8 = F7/2.
6. R2 = 510 5%.

FN2784 Rev 6.01 Page 21 of 24

Jan 22, 2020
82C59A

Die Characteristics
METALLIZATION:
Type: Si-Al-Cu
Thickness: Metal 1: 8kÅ  0.75kÅ
Metal 2: 12kÅ 1.0kÅ

GLASSIVATION:
Type: Nitrox
Thickness: 10kÅ  3.0kÅ

Metallization Mask Layout

82C59A

D0 D1 D2 D3 D4 D5 D6

CAS0 D7

CAS1 RD

GND WR

CS
CAS2

SP/EN VCC

INT A0

IR0 INTA

IR1 IR2 IR3 IR4 IR5 IR6 IR7

FN2784 Rev 6.01 Page 22 of 24

Jan 22, 2020
82C59A

Revision History
The revision history provided is for informational purposes only and is believed to be accurate, but not warranted. Please go to the web to make sure
that you have the latest revision.

DATE REVISION CHANGE

Jan 22, 2020 6.01 Updated Ordering Information table.

Removed About Intersil section.
Updated Disclaimer.

Sep 8, 2015 6.00 - Ordering Information Table on page 2.

- Added Revision History and About Intersil sections.

FN2784 Rev 6.01 Page 23 of 24

Jan 22, 2020
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