PC87413 datasheet(29/257 Pages) NSC

29 / 257 page

1.0 Signal/Pin Connection and Description (Continued)

Revision 1.2

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1.4.10

Clocks

1.4.11

Configuration Straps

Signal

Pin(s) I/O Buffer Type Power Well

Description

32KX1_32KCLKIN1

1. This pin is not 5-volt tolerant.

INOSC

VPP

32.768 KHz Crystal Input. Input from external crystal

oscillator circuitry.

32.768 KHz Clock Oscillator Input. Input from external

clock oscillator device.

32KX22

2. This pin is neither 5-volt tolerant nor back-drive protected.

OOSC

VPP

32.768 KHz Crystal Oscillator Output. Output to external

crystal oscillator circuitry.

LFCKOUT

O1/2

VSB

Low Frequency Clock Output. The Real-Time Clock

frequency (32.768 KHz) or a 1 Hz clock output.

CLKIN

INTS

VSB

3. The CLKIN signal source can be VDD powered.

Clock Input. 48 MHz for the Legacy functions or no input

clock.

HFCKOUT

O2/4

VSB

High Frequency Clock Output. Clock output for system

use.

Signal

Pin(s)

I/O Buffer Type Power Well

Description

BADDR

100

INCS

VDD

Base Address. Sampled at VDD Power-Up reset to determine

the base address of the conﬁguration Index-Data register pair,

as follows:

No pull-up resistor:

2Eh-2Fh

10 K

Ω external pull-up resistor: 4Eh-4Fh

TRIS

INCS

VDD

TRI-STATE Device. Sampled at VDD Power-Up reset to force

the device to ﬂoat all its output and I/O pins, as follows:

No pull-up resistor: pins active

4.7 K

Ω external pull-up resistor:pins ﬂoating

CKIN48

INCS

VSB

CLKIN 48 MHz. Sampled at VSB Power-Up reset to determine

the presence of the 48 MHz input clock at the CLKIN pin, as

follows:

No pull-up resistor:

no clock

10 K

Ω external pull-up resistor: 48 MHz clock

XCNF2-0

(PC87416,

PC87417)

32-34

INCS

VSB

X-Bus Default Conﬁguration. Sampled at VSB Power-Up reset

to set the conﬁguration of the X-Bus transactions.

Pins

2 1 0

Functionality

0 x x

No BIOS

1 0 0

With BIOS, XA11-4 multiplexed, XRDY disabled

1 0 1

With BIOS, XA11-4 multiplexed, XRDY enabled

1 1 0

With BIOS, XA11-4 direct, XRDY disabled

1 1 1

With BIOS, XA11-4 direct, XRDY enabled

Pulled to 0 by internal resistor or set to 1 by external 10 K

Ω pull-

up resistor.

ACBSA

(PC87413,

PC87417)

INCS

VSB

ACCESS.bus Slave Address. Sampled at VSB Power-Up reset

to determine the slave address of the device on the

ACCESS.bus, as follows

No pull-up resistor:

D8h, D9h

10 K

Ω external pull-up resistor: 60h, 61h

PC87413 Fiches technique(PDF) 29 Page - National Semiconductor (TI)

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