Signal Definitions
Table 5-1.
Signal Definitions (Sheet 4 of 8)
Name
Type
Description
Data strobe used to latch in D[63:0]#.
Notes
DSTBN[3:0]#
I/O
3
Signals
Associated Strobes
D[15:0]#, DBI0#
D[31:16]#, DBI1#
D[47:32]#, DBI2#
D[63:48]#, DBI3#
DSTBN0#
DSTBN1#
DSTBN2#
DSTBN3#
DSTBP[3:0]#
I/O
Data strobe used to latch in D[63:0]#.
3
Signals
Associated Strobes
D[15:0]#, DBI0#
D[31:16]#, DBI1#
D[47:32]#, DBI2#
D[63:48]#, DBI3#
DSTBP0#
DSTBP1#
DSTBP2#
DSTBP3#
FERR#/PBE#
O
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 Vol. 3 of the Intel Architecture
Software Developer’s Manual and the Intel Processor Identification and the CPUID
Instruction application note.
2
FORCEPR#
I
I
The FORCEPR# (force power reduction) input can be used by the platform to cause
the Dual-Core Intel Xeon Processor 5000 series to activate the Thermal Control
Circuit (TCC).
GTLREF_ADD_C0
GTLREF_ADD_C1
GTLREF_ADD_C0 and GTLREF_ADD_C1 determine the signal reference level for
AGTL+ address and common clock input lands on processor core 0 and processor
core 1 respectively. GTLREF_ADD is used by the AGTL+ receivers to determine if a
signal is a logical 0 or a logical 1. Please refer to the appropriate platform design
guidelines for additional details.
GTLREF_DATA_C0
GTLREF_DATA_C1
I
GTLREF_DATA_C0 AND GTLREF_DATA_C1 determine the signal reference level for
AGTL+ data input lands on processor core 0 and processor core 1 respectively.
GTLREF_DATA is used by the AGTL+ receivers to determine if a signal is a logical 0 or
a logical 1. Please refer to the appropriate platform design guidelines for additional
details.
HIT#
HITM#
I/O
I/O
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.
3
2
IERR#
O
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 (for example, NMI) by system core logic. The processor will keep IERR#
asserted until the assertion of RESET#.
This signal does not have on-die termination.
64
Dual-Core Intel® Xeon® Processor 5000 Series Datasheet
INTEL [ INTEL ]
