MultiProcessor Specification

INTR/LINT0

ICC BUS

NON-ISA INTERRUPT

INTERRUPT

ROUTING

NETWORK

I/O APIC

2

ISA INTERRUPT

I/O APIC

1

8259A-

EQUIVALENT

PICS

Figure 3-6. Multiple I/O APIC Configurations

3.7 RESET Support

To bring all circuitry in a computer system to an initial state, computer systems require a system- wide reset capability. To support multiple processors, a compliant system requires a processor- specific reset or initialization capability in addition to the typical system-wide reset and initialization capabilities.

The term “RESET” refers to the system-wide hard reset. It refers to the RESET signal on both Pentium and Intel486 processors or the RESET signal of the 82489DX APIC. (See Section 3.7.1.)

The term “INIT,” refers to either a system-wide soft reset/initialization or a processor-specific initialization. For example, the term “INIT” may refer to the INIT signal on the Pentium processor or to the RESET signal on the Intel486 processor. (See Sections 3.7.2. and 3.7.3.)

Because the INIT signal is available on the Pentium processor but not on the Intel486 processor, the remainder of this document uses the above-mentioned special definitions for the terms “INIT” and “RESET”:

3.7.1System-wide RESET

The system-wide RESET, as defined by this specification, refers to a hard or cold reset, which sets all circuitry, including processor, coprocessor, add-in cards, and control logic, to an initial state. A hard reset is the reset signal that is sent to all components of the system during a power-on

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Intel MultiProcessor manual Reset Support, System-wide Reset