Intel U2500 LE80539UE0092M User Manual
Product codes
LE80539UE0092M
Datasheet
53
Package Mechanical Specifications and Pin Information
FERR#/PBE#
Output
FERR# (Floating-point Error)PBE#(Pending Break Event) is a
multiplexed signal and its meaning is qualified with STPCLK#. When
STPCLK# is not asserted, FERR#/PBE# indicates a floating point
when the processor detects an unmasked floating-point error.
FERR# 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. When FERR#/PBE# is asserted, indicating a break
event, it will remain asserted until STPCLK# is deasserted.
Assertion of PREQ# when STPCLK# is active will also cause an
FERR# break event.
For additional information on the pending break event functionality,
including identification of support of the feature and enable/disable
information, refer to Volume 3 of the Intel
multiplexed signal and its meaning is qualified with STPCLK#. When
STPCLK# is not asserted, FERR#/PBE# indicates a floating point
when the processor detects an unmasked floating-point error.
FERR# 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. When FERR#/PBE# is asserted, indicating a break
event, it will remain asserted until STPCLK# is deasserted.
Assertion of PREQ# when STPCLK# is active will also cause an
FERR# break event.
For additional information on the pending break event functionality,
including identification of support of the feature and enable/disable
information, refer to Volume 3 of the Intel
®
Architecture Software
Developer’s Manual and AP-485, Intel
®
Processor Identification and
CPUID Instruction Application Note.
For termination requirements please contact your Intel
representative.
For termination requirements please contact your Intel
representative.
GTLREF
Input
GTLREF determines the signal reference level for AGTL+ input pins.
GTLREF should be set at 2/3 V
GTLREF should be set at 2/3 V
CCP
. GTLREF is used by the AGTL+
receivers to determine if a signal is a logical 0 or logical 1. Please
contact your Intel representative for more information regarding
GTLREF implementation.
contact your Intel representative for more information regarding
GTLREF implementation.
HIT#
HITM#
Input/
Output
Input/
Output
HIT# (Snoop Hit) and HITM# (Hit Modified) convey transaction
snoop operation results. Either 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.
snoop operation results. Either 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.
IERR#
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 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#, BINIT#, or INIT#.
For termination requirements please contact your Intel
representative.
internal error. Assertion of IERR# is usually accompanied by a
SHUTDOWN transaction on the 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#, BINIT#, or INIT#.
For termination requirements please contact your Intel
representative.
IGNNE#
Input
IGNNE# (Ignore Numeric Error) is asserted to force the processor
to ignore a numeric error and continue to execute noncontrol
floating-point instructions. If IGNNE# is deasserted, the processor
generates an exception on a noncontrol floating-point instruction if
a previous floating-point instruction caused an error. IGNNE# has
no effect when the NE bit in control register 0 (CR0) is set.
IGNNE# is an asynchronous signal. However, to ensure recognition
of this signal following an Input/Output write instruction, it must be
valid along with the TRDY# assertion of the corresponding Input/
Output Write bus transaction.
to ignore a numeric error and continue to execute noncontrol
floating-point instructions. If IGNNE# is deasserted, the processor
generates an exception on a noncontrol floating-point instruction if
a previous floating-point instruction caused an error. IGNNE# has
no effect when the NE bit in control register 0 (CR0) is set.
IGNNE# is an asynchronous signal. However, to ensure recognition
of this signal following an Input/Output write instruction, it must be
valid along with the TRDY# assertion of the corresponding Input/
Output Write bus transaction.
Table 17.
Signal Description (Sheet 5 of 9)
Name
Type
Description