AMD Duron Manual do Utilizador descarregar pdf (Página 71)

Chapter 9 Pin Descriptions 59

23802E—September 2000 AMD Duron™ Processor Data Sheet

Preliminary Information

The FID[3:0] signals are open-drain processor outputs that are

pulled High on the motherboard and sampled by the

Northbridge at the deassertion of RESET# to determine the SIP

(serialization initialization packet) that gets sent to the

processor. See the AMD System Bus Specification, order#21902

for more information about the SIP and SIP protocol.

The processor FID[3:0] outputs are open drain and 2.5V

tolerant. To prevent damage to the processor, if these signals

are pulled High to above 2.5 V, they must be electrically

isolated from the processor. For information about the FID[3:0]

isolation circuit, see the Motherboard PGA Design Guide, order#

90009.

FLUSH# Pin To the debug connector, this pin should be tied to VCC_CORE

with a 1-kohm resistor, and to SMI# with a 0-ohm resistor. The

0-ohm resistor is not populated.

IGNNE# Pin IGNNE# is an input from the system that tells the processor to

ignore numeric errors.

INIT# Pin INIT# is an input from the system that resets the integer

registers without affecting the floating-point registers or the

internal caches. Execution starts at 0FFFF FFF0h.

INTR Pin INTR is an input from the system that causes the processor to

start an interrupt acknowledge transaction that fetches the

8-bit interrupt vector and starts execution at that location.

JTAG Pins TCK (Q1), TMS (Q3), TDI (U1), TRST# (U3), and TDO (U5) are

the JTAG interface. Connect these pins directly to the

motherboard debug connector. Pullup TDI, TCK, TMS, and

TRST# to VCC_CORE with 1-kohm resistors.

K7CLKOUT and

K7CLKOUT# Pins

K7CLKOUT (AL21) and K7CLKOUT# (AN21) are each run for 2

to 3 inches and then terminated with a resistor pair, 100 ohms to

VCC_CORE and 100 ohms to VSS. The effective termination

resistance and voltage are 50 ohms and VCC_CORE/2.

Key Pins These 16 locations are for processor type keying for forwards

and backwards compatibility (G7, G9, G15, G17, G23, G25, N7,

Q7, Y7, AA7, AG7, AG9, AG15, AG17, AG27, and AG29).

Motherboard designers should treat key pins like NC (no

connect) pins. See “NC Pins” on page 60 for more information.

A socket designer has the option of creating a top mold piece

1 2 ... 66 67 68 69 70 71 72 73 74 75 76 ... 83 84

Sem comentários

AMD Duron Manual do Utilizador Página 71