VIA Technologies VT82C694X Pro Spécifications télécharger pdf (Page 37)

Design Guide - VT82C694X Apollo Pro133 with VT82C686A

Preliminary Revision 0.5, November 19, 1999 27 Motherboard Design Guidelines

Technologies, Inc.

We ConnectWe Connect

2.2.8 Power Up Configuration

During system restart and power up, system configuration information is latched at the rising edge of the RESET# signal. All

signals used to select power-up strap options are connected to either internal pull-up or pull-down resistors of minimum 50K ohms

(maximum is 150K ohm). These internal resistors select a default mode on the signal during reset. To enable different modes,

external pull-ups or pull-downs (the opposite of the internal pull-up or pull-down) of approximately 10K ohm can be connected to

particular signals. These pull-ups or pull-downs should be connected to the relative (e.g. 3.3V) power supply. For example, a 3-

pin jumper is used to select a pull-up (1-2) or pull-down (2-3) strapping as shown in Figure 2-20. The strapping state of logical 1

or logical 0 can be selected by using a jumper (shortage between pins).

4.7~10K

ohm

VCC3

VT82C686A

(South Bridge)

ROMCS#

JCONF

Header 1x3

JCONF

1-2

2-3

CPU Configuration

Slot-1 or Socket-370

Socket-7

Figure 2-20. A Typical Example of a 3-pin Jumper Strapping Circuit

1 2 ... 32 33 34 35 36 37 38 39 40 41 42 ... 139 140

Pas de commentaire

VIA Technologies VT82C694X Pro Spécifications Page 37