80546KF Datasheet, PDF (125/138 Pages) Intel Corporation – 64-bit Intel Xeon Processor MP with up to 8MB L3 Cache

Features
8.4.9.9 Checksums
The PIROM includes multiple checksums. Table 8-18 includes the checksum values for each
section defined in the 128 byte ROM, except Other Data.
Table 8-18. 128 Byte ROM Checksum Values
Section
Header
Processor Data
Processor Core Data
Cache Data
Package Data
Part Number Data
Feature Data
Other Data
Checksum Address
0Dh
15h
24h
31h
37h
6Fh
7Dh
None Defined
Checksums are automatically calculated and programmed by Intel. The first step in calculating the
checksum is to add each byte from the field to the next subsequent byte. This result is then negated
to provide the checksum.
Example: For a byte string of AA445Ch, the resulting checksum will be B6h.
AA = 10101010
44 = 01000100
5C = 0101100
AA + 44 + 5C = 01001010
Negate the sum: 10110101 +1 = 101101 (B6h)
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64-bit Intel^® Xeon™ Processor MP with up to 8MB L3 Cache Datasheet
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