82C836B Ver la hoja de datos (PDF) - Unspecified

Número de pieza

componentes Descripción

fabricante

82C836B

Single-Chip 386sx AT

Unspecified 

s Reset Strap Options

Functional Description

Table 3-1. Pins for Strap Options

Signal

-DACK0

-DACK1

-DACK2

-DACK3

-DACK5

-DACK6

-DACK7

↑ = Pull-up

Strap Function

SENSE0

SENSE1

VIDEO

NA/STCYC

-EXRTC

Reserved

-ROM16

↓ = Pull-down

Description

Determines ICR 45H bit 0

Determines ICR 45 bit 1

Video on SD ↑ or XD bus ↓; also determines ICR 45H bit 2

-NA↑ or -STCYC ↓ Function

Internal RTC ↑ or external ↓

(Should be pulled up)

8-bit ROM ↑ or 16-bit ROM ↓

Figure 3-1. Pull-Low Function----Alternate Implementation

+5V

-XRST

10K

7407

-DACKn

SENSE0 and SENSE1 are general purpose and can be used according to specific system

requirements. -DACK2 can also be used as a general purpose SENSE2 if ICR44H is

appropriately programmed to specify where the video controller resides.

If external Real Time Clock is used (-DACK5 pulled low), the -RTCCS pin (MFP5)

should be connected to PWRGOOD through a diode as shown in Figure 3-2. This

insures that the standby enable bit (ICR 60H) will always be cleared on power-up.

Otherwise, the 82C836 could power-up with standby mode enabled, which would

prevent -DACK5 from being sampled properly. See the ICR 60H description in

Section 4, Configuration Registers for further explanation of standby initialization.

3-2 Revision 3.0

PRELIMINARY

Chips and Technologies, Inc.

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