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Device Overview

The PC87782 is a microcontroller with all system interfaces,

interrupt logic, program memory, data memory, and I/O ports

included on-chip, making it well-suited to PC monitoring ap-

plications. The block diagram on the page 1 of the data sheet

shows the major on-chip components of the PC87782. Fig-

ure 1 shows a connection diagram of the PC87782 to the PC

system.

Figure 1. PC87782 Stand-Alone System Connection

or

CLOCK

PC87782

HMR

HA

HD0-7

HIOR

HIOW

PB5-7

PC1-7

CRYSTAL

32.768 kHz

GND (4)

POWER

SUPPLY

System

HCSA

HCSB

Configuration

Inputs

HPWRON

PC0

FAN3

FAN2

FAN1

PI 2-7

Analog Inputs (6)

PI 0

AMP0

PI 1

AMP1

-12V Monitor

and Feedback

-5V Monitor

and Feedback

SCL

SDA

PB0-4

VID Inputs

General-Purpose

Input/Output Pins

PL0-7

CHASSIS

RING

Other(6): BTI,

SOFT_ON

RX_CLK

RX_DV

RX_ER

RXD0-3

TXD0-3

TX_CLK

TX_EN

COL

CRS

MAC_ISOL

Fan Inputs

PFAIL

NTEST

NAND Test

Output

Power Fail

Interrupt (NMI)

(MIWU)

Management

Bus (SMB)

IRQA

IRQB

SWIN, etc.

RESET

Chip Reset

PC3

PF0

PF1

PF2

PF3

PF4

PF5

PF6

PF7

IN0

IN1

OUT0

OUT1

LOSTPKT

Receive

Buffer Mgmt.

Status

(All pulled high for

normal operation)

DAOUT

Analog Output