
Chapter 3
Software Environment
27
23542A/0—September 2000
AMD-K6-2E+ Embedded Processor Data Sheet
Preliminary Information
3
Software Environment
This chapter provides a general overview of the AMD-K6-2E+
processor’s x86 software environment and briefly describes the
data types, registers, operating modes, interrupts, and
instructions supported by the AMD-K6-2E+ processor
architecture and design implementation.
The AMD-K6-2E+ processor implements the same ten Model-
Specific Registers (MSRs) as the AMD-K6-2 and AMD-K6-2E
processors Model 8/[F:8], and the bits and fields within these
ten MSRs are defined identically. The AMD-K6-2E+ processor
supports an additional MSR for cache control. The low-power
versions of the AMD-K6-2E+ processor support a twelfth MSR
to control the AMD PowerNow! technology functions.
See “Model-Specific Registers (MSR)” on page 44 for the MSR
definitions.
The model number for the AMD-K6-2E+ processor is Model
D/[7:4], where the actual stepping can be any value in the range
[7:4].
3.1
Registers
The AMD-K6-2E+ processor contains all the registers defined
by the x86 architecture, including general-purpose, segment,
floating-point, MMX/3DNow!, EFLAGS, control, task, debug,
test, and descriptor/memory-management registers.
In addition, this chapter provides information on the
AMD-K6-2E+ processor MSRs.
Note:
Areas of the register designated as
Reserved
should not be
modified by software.