Chapter 6
AMD PowerNow! Technology
143
23542A/0—September 2000
AMD-K6-2E+ Embedded Processor Data Sheet
Preliminary Information
6
AMD PowerNow! Technology
The AMD PowerNow! technology is an advanced second-
generation power management feature that reduces the overall
power consumed by the processor through control of voltage
and frequency. This power saving technology is designed to be
dynamic and flexible by enabling instant “on-the-fly” and
independent control of both the processor’s core voltage and
frequency.
AMD PowerNow! technology can be used in conjunction with
the existing power management schemes in an embedded
system to provide a better combination of performance and
power savings than previously possible.
6.1
Enhanced Power Management Features
AMD PowerNow! technology-enabled processors include two
new f eat ure s spe cific ally designed to enhanc e powe r
management functionality:
s
Dynamic core frequency control
s
Dynamic core voltage control
These enhanced power management features are accessed and
controlled through an I/O block and two registers:
s
An aligned 16-byte block of I/O address space is defined by
the Enhanced Power Management Register (EPMR).
s
The Enhanced Power Management Register (EPMR) is
supported on low-power versions of the processor only.
s
The Processor State Observability Register (PSOR) is
defined differently on the low-power versions of the
AMD-K6-2E+
processor
to
support
AMD
PowerNow!
technology features.
The EPMR and PSOR registers and the I/O block are defined in
this section, followed by a discussion of how to implement and
use the AMD PowerNow! technology features (see
“DynamicEmbedded AMD-K6 Processors BIOS Design Guide Application
Note, order# 23913, contains additional information.