AMD 8 manual Detailed Pin Descriptions, See the AMD Athlon System Bus Specification, order#

Preliminary Information

AMD Athlon™ XP Processor Model 8 Data Sheet 25175H— March 2003

11.3Detailed Pin Descriptions

	The information in this section pertains to Table 25 on page 66.
A20M# Pin	A20M# is an input from the system used to simulate address
	wrap-around in the 20-bit 8086.
AMD Pin	AMD Socket A processors do not implement a pin at location
	AH6. All Socket A designs must have a top plate or cover that
	blocks this pin location. When the cover plate blocks this
	location, a non-AMD part (e.g., PGA370) does not fit into the
	socket. However, socket manufacturers are allowed to have a
	contact loaded in the AH6 position. Therefore, motherboard
	socket design should account for the possibility that a contact
	could be loaded in this position.
AMD Athlon™	See the AMD Athlon™ System Bus Specification, order# 21902
System Bus Pins	for information about the system bus pins — PROCRDY,
	PWROK, RESET#, SADDIN[14:2]#, SADDINCLK#,
	SADDOUT[14:2]#, SADDOUTCLK#, SDATA[63:0]#,
	SDATAINCLK[3:0]#, SDATAINVALID#, SDATAOUTCLK[3:0]#,
	SDATAOUTVALID#, SFILLVALID#.
Analog Pin	Treat this pin as a NC.
APIC Pins, PICCLK,	The Advanced Programmable Interrupt Controller (APIC) is a
PICD[1:0]#	feature that provides a flexible and expandable means of
	delivering interrupts in a system using an AMD processor. The
	pins, PICD[1:0], are the bi-directional message-passing signals
	used for the APIC and are driven to the Southbridge or a
	dedicated I/O APIC. The pin, PICCLK, must be driven with a
	valid clock input.
	For more information, see Table 19, “APIC Pin AC and DC
	Characteristics,” on page 44.
CLKFWDRST Pin	CLKFWDRST resets clock-forward circuitry for both the system
	and processor.
CLKIN, RSTCLK	Connect CLKIN with RSTCLK and name it SYSCLK. Connect
(SYSCLK) Pins	CLKIN# with RSTCLK# and name it SYSCLK#. Length match
	the clocks from the clock generator to the Northbridge and
	processor.
	See “SYSCLK and SYSCLK#” on page 79 for more information.

74 Pin Descriptions Chapter 11