FLUSH# is serviced during the AutoHALT state. Once the FLUSH# is complete the processor
returns to the AutoHALT state.
The system can generate a STPCLK# while the processor is in the AutoHALT Power Down state.
When the system deasserts the STPCLK# interrupt, the processor returns execution to the HALT
Stop-Grant State—State 3
The Stop-Grant state on the processor is entered when the STPCLK# signal is asserted.
Since the AGTL signal balls receive power from the system bus, these balls should not be driven.
(allowing the level to return to V
this state. In addition, all other input balls on the system bus should be driven to the inactive state.
BINIT# and FLUSH# are not serviced during the Stop-Grant state.
RESET# causes the processor to immediately initialize itself, but the processor stays in Stop-Grant
state. A transition back to the Normal state occurs with the deassertion of the STPCLK# signal.
A transition to the HALT/Grant Snoop state occurs when the processor detects a snoop on the
system bus (see
assertion of the SLP# signal.
While in Stop-Grant State, SMI#, INIT#, and LINT[1:0] are latched by the processor, and only
serviced when the processor returns to the Normal state. Only one occurrence of each event is
recognized and serviced upon return to the Normal state.
HALT/Grant Snoop State—State 4
The processor responds to snoop transactions on the system bus while in Stop-Grant state or in
AutoHALT Power Down state. During a snoop transaction, the processor enters the HALT/Grant
Snoop state. The processor stays in this state until the snoop on the system bus has been serviced
(whether by the processor or another agent on the system bus). After the snoop is serviced, the
processor returns to the Stop-Grant state or AutoHALT Power Down state, as appropriate.
Sleep State—State 5
The Sleep state is a very low power state in which the processor maintains its context, maintains
the phase-locked loop (PLL), and has stopped all internal clocks. The Sleep state can only be
entered from the Stop-Grant state. Once in the Stop-Grant state, the SLP# ball can be asserted,
causing the processor to enter the Sleep state. The SLP# ball is not recognized in the Normal or
Snoop events that occur while in Sleep State or during a transition into or out of Sleep state will
cause unpredictable behavior.
In the Sleep state, the processor is incapable of responding to snoop transactions or latching
interrupt signals. No transitions or assertions of signals (with the exception of SLP# or RESET#)
are allowed on the system bus while the processor is in Sleep state. Any transition on an input
signal before the processor has returned to Stop-Grant state will result in unpredictable behavior.
) to minimize the power drawn by the termination resistors in
2.5.4). A transition to the Sleep state (see
III Processor 512K
2.5.5) occurs with the