User Guide

Identification Information
Specification Update 7
Identification Information
Component Identification via Programming Interface
The processor stepping can be identified by the following register contents:
Table 1. Y/U-Processor Lines Component Identification
Reserved Extended
Family
Extended
Model
Reserved Processor
Type
Family
Code
Model
Number
Stepping
ID
31:28 27:20 19:16 15:14 13:12 11:8 7:4 3:0
0000000b 1000b 00b 0110b 1110b xxxxb
Table 2. S/H-Processor Lines Component Identification
Reserved Extended
Family
Extended
Model
Reserved Processor
Type
Family
Code
Model
Number
Stepping
ID
31:28 27:20 19:16 15:14 13:12 11:8 7:4 3:0
0000000b 1001b 00b 0110b 1110b xxxxb
Notes:
1. The Extended Family, Bits [27:20] are used in conjunction with the Family
Code, specified in Bits[11:8], to indicate whether the processor belongs to the
Intel386™, Intel486™, Pentium
®
, Pentium 4, or Intel
®
Core™ processor
family.
2. The Extended Model, Bits [19:16] in conjunction with the Model Number,
specified in Bits [7:4], are used to identify the model of the processor within
the processor’s family.
3. The Family Code corresponds to Bits [11:8] of the EDX register after RESET,
Bits [11:8] of the EAX register after the CPUID instruction is executed with a 1
in the EAX register, and the generation field of the Device ID register
accessible through Boundary Scan.
4. The Model Number corresponds to Bits [7:4] of the EDX register after RESET,
Bits [7:4] of the EAX register after the CPUID instruction is executed with a 1
in the EAX register, and the model field of the Device ID register accessible
through Boundary Scan.
5. The Stepping ID in Bits [3:0] indicates the revision number of that model. See
Table 1 for the processor stepping ID number in the CPUID information.
6. Please refer to Kaby Lake Processor BIOS Writers Guide for additional
information. When EAX is initialized to a value of ‘1’, the CPUID instruction
returns the Extended Family, Extended Model, Processor Type, Family Code,
Model Number and Stepping ID value in the EAX register. Note that the EDX
processor signature value after reset is equivalent to the processor signature
output value in the EAX register.
Cache and TLB descriptor parameters are provided in the EAX, EBX, ECX and EDX registers after
the CPUID instruction is executed with a 2 in the EAX register.