Intel 64 and IA-32 Architectures Software Developers Manual Volume 3B, System Programming Guide Part 2

Table Of Contents
Vol. 3 B-167
MODEL-SPECIFIC REGISTERS (MSRS)
B.9 MSRS IN PENTIUM PROCESSORS
The following MSRs are defined for the Pentium processors. The P5_MC_ADDR,
P5_MC_TYPE, and TSC MSRs (named IA32_P5_MC_ADDR, IA32_P5_MC_TYPE, and
IA32_TIME_STAMP_COUNTER in the Pentium 4 processor) are architectural; that is,
code that accesses these registers will run on Pentium 4 and P6 family processors
without generating exceptions (see Section B.1, “Architectural MSRs”). The CESR,
CTR0, and CTR1 MSRs are unique to Pentium processors; code that accesses these
registers will generate exceptions on Pentium 4 and P6 family processors.
Table B-12. MSRs in the Pentium Processor
Register
Address
Hex Dec Register Name Bit Description
0H 0 P5_MC_ADDR See Section 14.9.2, “Pentium
Processor Machine-Check
Exception Handling.
1H 1 P5_MC_TYPE See Section 14.9.2, “Pentium
Processor Machine-Check
Exception Handling.
10H 16 TSC See Section 18.11, “Time-Stamp Counter.
11H 17 CESR See Section 18.26.1, “Control and Event Select Register (CESR).
12H 18 CTR0 Section 18.26.3, “Events Counted.
13H 19 CTR1 Section 18.26.3, “Events Counted.