Land Listing and Signal Descriptions
Table 25.
Signal Description (Sheet 1 of 9)
Name
Type
Description
DSTBP[3:0]# are the data strobes used to latch in D[63:0]#.
Signals
Associated Strobe
D[15:0]#, DBI0#
D[31:16]#, DBI1#
D[47:32]#, DBI2#
D[63:48]#, DBI3#
DSTBP0#
DSTBP1#
DSTBP2#
DSTBP3#
Input/
Output
DSTBP[3:0]#
FC signals are signals that are available for compatibility with other
processors.
FCx
Other
FERR#/PBE# (floating point error/pending break event) is a
multiplexed signal and its meaning is qualified by STPCLK#. When
STPCLK# is not asserted, FERR#/PBE# indicates a floating-point
error and will be asserted when the processor detects an unmasked
floating-point error. When STPCLK# is not asserted, FERR#/PBE#
is similar to the ERROR# signal on the Intel 387 coprocessor, and is
included for compatibility with systems using MS-DOS*-type
floating-point error reporting. When STPCLK# is asserted, an
assertion of FERR#/PBE# indicates that the processor has a
pending break event waiting for service. The assertion of FERR#/
PBE# indicates that the processor should be returned to the Normal
state. For additional information on the pending break event
functionality, including the identification of support of the feature
and enable/disable information, refer to volume 3 of the Intel® 64
and IA-32 Architecture Software Developer’s Manual and the Intel
Processor Identification and the CPUID Instruction application note.
FERR#/PBE#
Output
GTLREF[1:0] determine the signal reference level for GTL+ input
signals. GTLREF is used by the GTL+ receivers to determine if a
signal is a logical 0 or logical 1.
GTLREF[1:0]
Input
Input/
Output
HIT# (Snoop Hit) and HITM# (Hit Modified) convey transaction
snoop operation results. Any FSB agent may assert both HIT# and
HITM# together to indicate that it requires a snoop stall, which can
be continued by reasserting HIT# and HITM# together.
HIT#
HITM#
Input/
Output
IERR# (Internal Error) is asserted by a processor as the result of
an internal error. Assertion of IERR# is usually accompanied by a
SHUTDOWN transaction on the processor FSB. This transaction
may optionally be converted to an external error signal (e.g., NMI)
by system core logic. The processor will keep IERR# asserted until
the assertion of RESET#.
IERR#
Output
This signal does not have on-die termination. Refer to Section 2.5.2
for termination requirements.
68
Datasheet
INTEL [ INTEL ]
