Datasheet

R
30 Specification Update
V41. A 16-bit Address Wrap Resulting from a Near Branch (Jump or Call) May Cause
an Incorrect Address to Be Reported to the #GP Exception Handler
Problem: If a 16-bit application executes a branch instruction that causes an address wrap to a target address
outside of the code segment, the address of the branch instruction should be provided to the general
protection exception handler. It is possible that, as a result of this erratum, that the general protection
handler may be called with the address of the branch target.
Implication: The 16-bit software environment which is affected by this erratum, will see that the address reported by
the exception handler points to the target of the branch, rather than the address of the branch instruction.
Workaround: None identified
Status: For the steppings affected, see the Summary Tables of Changes.
V42. FOPCODE Routine signals Debug Exception (#DB) if a Data Breakpoint Is Set on
an FP Instruction
Problem: The default Microcode Floating Point Event Handler routine executes a series of loads to obtain data
about the FP instruction that is causing the FP event. If a data breakpoint is set on the instruction causing
the FP event, the load in the microcode routine will trigger the data breakpoint resulting in a Debug
Exception.
Implication: An incorrect Debug Exception (#DB) may occur if data breakpoint is placed on an FP instruction. Intel
has not observed this erratum with any commercially available software or system.
Workaround: None identified.
Status: For the steppings affected, see the Summary Tables of Changes
V43. xAPIC May Not Report Some Illegal Vector Errors
Problem: The local xAPIC has an Error Status Register, which records all errors. The bit 6 (the Receive Illegal
Vector bit) of this register, is set when the local xAPIC detects an illegal vector in a received message.
When an illegal vector error is received on the same internal clock that the error status register is being
written (due to a previous error), bit 6 does not get set and illegal vector errors are not flagged.
Implication: The xAPIC may not report some Illegal Vector errors when they occur at approximately the same time
as other xAPIC errors. The other xAPIC errors will continue to be reported.
Workaround: None identified.
Status: For the steppings affected, see the Summary Tables of Changes.