Intel 8XC196NT A.3 DEFAULT CONDITIONS, 87C196CB Supplement, Table A-5. 87C196CB Pin Status

Models: 8XC196NT 87C196CB

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A.3 DEFAULT CONDITIONS

87C196CB Supplement

 

 

Table A-3. Signal Descriptions (Continued)

Name

Type

Description

 

 

 

WRL#

O

Write Low

 

 

During 16-bit bus cycles, this active-low output signal is asserted for low-byte

 

 

writes and word writes. During 8-bit bus cycles, WRL# is asserted for all write

 

 

operations.

 

 

WRL# is multiplexed with P5.2, SLPWR#, and WR#.

 

 

The chip configuration register 0 (CCR0) determines whether this pin

 

 

functions as WR# or WRL#. CCR0.2 = 1 selects WR#; CCR0.2 = 0 selects

 

 

WRL#.

XTAL1

I

Input Crystal/Resonator or External Clock Input

 

 

Input to the on-chip oscillator and the internal clock generators. The internal

 

 

clock generators provide the peripheral clocks, CPU clock, and CLKOUT

 

 

signal. When using an external clock or crystal instead of the on-chip oscillator,

 

 

connect the clock input to XTAL1. The external clock signal must meet the VIH

 

 

specification for XTAL1 (see datasheet).

XTAL2

O

Inverted Output for the Crystal/Resonator

 

 

Output of the on-chip oscillator inverter. Leave XTAL2 floating when the design

 

 

uses a external clock source instead of the on-chip oscillator.

A.3 DEFAULT CONDITIONS

Table A-5 lists the default functions of the I/O and control pins of the microcontroller with their values during various operating conditions. Table A-4 defines the symbols used to represent the pin status. Refer to the DC Characteristics table in the datasheet for actual specifications for VOL, VIL, VOH, and VIH.

Table A-4. Definition of Status Symbols

Symbol

Definition

0Voltage less than or equal to VOL, VIL

1Voltage greater than or equal to VOH, VIH

HiZ

High impedance

LoZ0

Low impedance; strongly driven low

LoZ1

Low impedance; strongly driven high

Symbol

Definition

 

 

MD0

Medium pull-down

MD1

Medium pull-up

WK0

Weak pull-down

WK1

Weak pull-up

ODIO

Open-drain I/O

Table A-5. 87C196CB Pin Status

Port Pins

Multiplexed

Status During

Status During

Status During

With

Reset

Idle

Powerdown

 

 

 

 

 

 

P0.7:4

ACH7:4

HiZ

HiZ

HiZ

P1.7:0

EPA7:0

WK1

(Note 3)

(Note 3)

P2.0

TXD

WK1

(Note 3)

(Note 3)

P2.1

RXD

WK1

(Note 3)

(Note 3)

A-14

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Intel 8XC196NT user manual A.3 DEFAULT CONDITIONS, 87C196CB Supplement, Table A-3. Signal Descriptions Continued