The contents of this document are provided in connection with Advanced Micro
Devices, Inc. (“AMD”) products. AMD makes no representations or warranties with
respect to the accuracy or completeness of the contents of this publication and
reserves the right to make changes to specifications and product descriptions at
any time without notice. No license, whether express, implied, arising by estoppel
or otherwise, to any intellectual property rights is granted by this publication.
Except as set forth in AMD’s Standard Terms and Conditions of Sale, AMD
assumes no liability whatsoever, and disclaims any express or implied warranty,
relating to its products including, but not limited to, the implied warranty of merchantability, fitness for a particular purpose, or infringement of any intellectual
property right.
AMD’s products are not designed, intended, authorized or warranted for use as
components in systems intended for surgical implant into the body, or in other
applications intended to support or sustain life, or in any other application in which
the failure of AMD’s product could create a situation where personal injury, death,
or severe property or environmental damage may occur. AMD reserves the right to
discontinue or make changes to its products at any time without notice.
Contacts
www.amd.com
Trademarks
AMD, the AMD Arrow logo, AMD Athlon, Geode, GeodeLink, 3DNow!, and combinations thereof, are trademarks of
Advanced Micro Devices, Inc.
Linux is a registered trademark of Linus Torvalds.
WinBench is a registered trademark of Ziff Davis, Inc.
Windows is a registered trademark of Microsoft Corporation in the United States and/or other jurisdictions.
Pentium is a registered trademark and MMX is a trademark of Intel Corporation in the United States and/or other jurisdictions.
Other product names used in this publication are for identification purposes only and may be trademarks of their respective
companies.
Table 6-87.Bootstrap Bit Settings and Reset State of GLCP_SYS_RSTPLL (PW1 and IRQ13 = 0) . .556
Table 6-88.Bootstrap Bit Settings and Reset State of GLCP_SYS_RSTPLL (PW1 and IRQ13 vary) . . 557
AMD Geode™ LX processors are integrated x86 processors specifically designed to power embedded devices for
entertainment, education, and business. Serving the needs
of consumers and business professionals alike, it’s an
excellent solution for embedded applications, such as thin
clients, interactive set-top boxes, single board computers,
and mobile computing devices.
Available with a core voltage of 1.2V, 1.25V, or 1.4V it offers
extremely low typical power consumption leading to longer
battery life and enabling small form-factor, fanless designs.
While the processor core provides maximum compatibility
with the vast amount of Internet content available, the intelligent integration of several other functions, including
graphics and video datapaths, offers a true system-level
multimedia solution.
For implementation details and suggestions for this device,
see the supporting documentation (i.e., application notes,
schematics, etc.) on the AMD Embedded Developer Support Web site (http://wwwd.amd.com/dev
1
, NDA required).
SYSREF
DOTREF
SDCLKs
64-Bit
DDR
Test/Reset
Interface
AMD Geode™
Companion
Device
Clock Module
System PLL
CPU PLL
DOTCLK PLL
GeodeLink™
Memory
Controller (GLMC)
64-bit DDR SDRAM
GeodeLink™
Control
Processor (GLCP)
Power Mgmnt
Te s t
Diagnostic
Companion I/F
Security Block
128-bit AES
(CBC/ECB)
Tr u e
Random Number
Generator
64 KB L1 I-cache
64 KB L1 D-cache
TLB
128 KB L2 cache
GeodeLink™ Interface Unit 0
GeodeLink™ Interface Unit 1
Video Input
Port (VIP)
CPU Core
Integer
Unit
(GLIU0)
(GLIU1)
GeodeLink™
Load/Store
Bus Controller
PCI Bridge
(GLPCI)
MMU
FPU
TFT
Controller/
Video
Output
Port (VOP)
Graphics Processor (GP)
BLT Engine
ROP Unit
Alpha Compositing
Rotation BLT
Display Controller (DC)
Compression Buffer
Palette RAM
Timing
Graphics Filter/Scaling
HW VGA
RGBYUV
Video Processor (VP)
Video Scalar
Video Mixer
Alpha Blender
1 KB
LUT
3x8-Bit DAC
EEPROM on package
(optional)
VIP
PCI
TFT/VOP
CRT
Figure 1-1. Internal Block Diagram
AMD Geode™ LX Processors Data Book 11
33234H
Overview
1.2Features
General Features
■ Functional blocks include:
—CPU Core
— GeodeLink™ Control Processor
— GeodeLink Interface Units
— GeodeLink Memory Controller
— Graphics Processor
— Display Controller
— Video Processor
– TFT Controller/Video Output Port
— Video Input Port
— GeodeLink PCI Bridge
— Security Block
■ 0.13 micron process
■ Packaging:
— 481-Terminal BGU (Ball Grid Array Cavity Up) with
internal heatspreader
■ Single packaging option supports all features
■ Industrial temperature range available for the
LX 800@0.9W processor*
CPU Processor Features
■ x86/x87-compatible CPU core
■ Performance:
— Processor frequency: up to 600 MHz
— Dhrystone 2.1 MIPs: 150 to 450
— Fully pipelined FPU
■ Fully pipelined single precision FPU hardware with
microcode support for higher precisions
GeodeLink™ Control Processor
■ JTAG interface:
— ATPG, Full Scan, BIST on all arrays
— 1149.1 Boundary Scan compliant
■ ICE (in-circuit emulator) interface
■ Reset and clock control
■ Designed for improved software debug methods and
performance analysis
■ Power Management:
— LX 900@1.5W processor* (Unterminated):
Total Dissipated Power (TDP) 5.1W,
2.6W typical @ 600 MHz max power
— LX 800@0.9W processor* (Unterminated):
Total Dissipated Power (TDP) 3.6W,
1.8W typical @ 500 MHz max power
— LX 700@0.8W processor* (Unterminated):
Total Dissipated Power (TDP) 3.1W,
1.3W typical @ 433 MHz max power
— LX 600@0.7W processor* (Unterminated):
Total Dissipated Power (TDP) 2.8W,
1.2W typical @ 366 MHz max power
— GeodeLink active hardware power management
— Hardware support for standard ACPI software power
management
— I/O companion SUSP/SUSPA power controls
— Lower power I/O
— Wakeup on SMI/INTR
■ Works in conjunction with the AMD Geode™ CS5536
(USB 2.0) or CS5535 (USB 1.1) companion device
GeodeLink™ Architecture
■ High bandwidth packetized uni-directional bus for
internal peripherals
■ Standardized protocol to allow variants of products to be
developed by adding or removing modules
■ GeodeLink Control Processor (GLCP) for diagnostics
and scan control
■ Dual GeodeLink Interface Units (GLIUs) for device inter-
connect
GeodeLink™ Memory Controller
■ Integrated memory controller for low latency to CPU and
on-chip peripherals
■ 64-bit wide DDR SDRAM bus operating frequency:
— 200 MHz, 400 MT/S
■ Supports unbuffered DDR DIMMS using up to 2 GB
DRAM technology
■ Supports up to 2 DIMMS (16 devices max)
2D Graphics Processor
■ High performance 2D graphics controller
■ Alpha BLT
■ Windows
®
GDIGUI acceleration:
— Hardware support for all Microsoft RDP codes
■ Command buffer interface for asynchronous BLTs
■ Second pattern channel support
■ Hardware screen rotation
*The AMD Geode LX 900@1.5W processor operates at 600 MHz, the AMD Geode LX 800@0.9W processor operates at 500 MHz, the
AMD Geode LX 700@0.8W processor operates at 433 MHz and the AMD Geode LX 600@.07W processor operates at 366 MHz. Model
numbers reflect performance as described here: http://www.amd.com/connectivitysolutions/geodelxbenchmark
■ Electronic Code Book (ECB) or Cipher Block Chaining
(CBC)128-bit AES hardware support
■ True random number generator (TRNG)
Video Processor
■ Supports video scaling, mixing and VOP
■ Hardware video up/down scalar
■ Graphics/video alpha blending and color key muxing
■ Digital VOP (SD and HD) or TFT outputs
■ Legacy RGB mode
■ VOP supports SD and HD 480p, 480i, 720p, and 1080i
■ VESA 1.1, 2.0 and BT.601 24-bit (out only), BT.656
compliant
Integrated Analog CRT DAC, System Clock PLLs and
Dot Clock PLL
■ Integrated Dot Clock PLL with up to 350 MHz clock
■ Integrated 3x8-bit DAC with up to 350 MHz sampling
■ Integrated x86 core PLL
■ Memory PLL
AMD Geode™ LX Processors Data Book 13
33234H
Overview
14AMD Geode™ LX Processors Data Book
Architecture Overview33234H
2.0Architecture Overview
2
The CPU Core provides maximum compatibility with the
vast amount of Internet content available while the intelligent integration of several other functions, including graphics, makes the AMD Geode™ LX processor a true systemlevel multimedia solution.
The AMD Geode LX processor can be divided into major
functional blocks (as shown in Figure 1-1 on page 11):
• CPU Core
• GeodeLink™ Control Processor
• GeodeLink Interface Units
• GeodeLink Memory Controller
• Graphics Processor
• Display Controller
• Video Processor
— TFT Controller/Video Output Port
• Video Input Port
• GeodeLink PCI Bridge
• Security Block
2.1CPU Core
The x86 core consists of an Integer Unit, cache memory
subsystem, and an x87 compatible FPU (Floating Point
Unit). The Integer Unit contains the instruction pipeline and
associated logic. The memory subsystem contains the
instruction and data caches, translation look-aside buffers
(TLBs), and an interface to the GeodeLink Interface Units
(GLIUs).
The instruction set supported by the core is a combination
of Intel Pentium
AMD Geode LX processor specific instructions. Specifically, it supports the Pentium, Pentium Pro, AMD 3DNow!™
technology and MMX™ instructions for the AMD Athlon
processor. It supports a subset of the specialized
AMD Geode LX processor instructions including special
SMM instructions. The CPU Core does not support the
entire Katmai New Instruction (KNI) set as implemented in
the Pentium 3. It does support the MMX instructions for the
AMD Athlon processor, which are a subset of the
Pentium 3 KNI instructions.
®
processor, AMD Athlon™ processor, and
2.1.1Integer Unit
The Integer Unit consists of a single issue 8-stage pipeline
and all the necessary support hardware to keep the pipeline running efficiently.
The instruction pipeline in the integer unit consists of eight
stages:
1) Instruction Prefetch - Raw instruction data is fetched
from the instruction memory cache.
2) Instruction Pre-decode - Prefix bytes are extracted
from raw instruction data. This decode looks-ahead to
the next instruction and the bubble can be squashed if
the pipeline stalls down stream.
3) Instruction Decode - Performs full decode of instruction data. Indicates instruction length back to the
Prefetch Unit, allowing the Prefetch Unit to shift the
appropriate number of bytes to the beginning of the
next instruction.
4) Instruction Queue - FIFO containing decoded x86
instructions. Allows Instruction Decode to proceed
even if the pipeline is stalled downstream. Register
reads for data operand address calculations are performed during this stage.
5) Address Calculation #1 - Computes linear address of
operand data (if required) and issues request to the
Data Memory Cache. Microcode can take over the
pipeline and inject a micro-box here if multi-box
instructions require additional data operands.
6) Address Calculation #2 - Operand data (if required)
is returned and set up to the Execution stage with no
bubbles if there was a data cache hit. Segment limit
checking is performed on the data operand address.
The µROM is read for setup to Execution Unit.
7) Execution Unit - Register and/or data memory fetch
fed through the Arithmetic Logic Unit (ALU) for arithmetic or logical operations. µROM always fires for the
first instruction box down the pipeline. Microcode can
take over the pipeline and insert additional boxes here
if the instruction requires multiple Execution Unit
stages to complete.
8) Writeback - Results of the Execution Unit stages are
written to the register file or to data memory.
AMD Geode™ LX Processors Data Book 15
33234H
Architecture Overview
2.1.2Memory Management Unit
The memory management unit (MMU) translates the linear
address supplied by the integer unit into a physical address
to be used by the cache unit and the internal bus interface
unit. Memory management procedures are x86-compatible, adhering to standard paging mechanisms.
The MMU also contains a load/store unit that is responsible
for scheduling cache and external memory accesses. The
load/store unit incorporates two performance-enhancing
features:
• Load-store reordering gives memory reads required by
the integer unit a priority over writes to external memory.
• Memory-read bypassing eliminates unnecessary
memory reads by using valid data from the execution
unit.
2.1.3Cache and TLB Subsystem
The cache and TLB subsystem of the CPU Core supplies
the integer pipeline with instructions, data, and translated
addresses (when necessary). To support the efficient delivery of instructions, the cache and TLB subsystem has a
single clock access 64 KB 16-way set associative instruction cache and a 16-entry fully associative TLB. The TLB
performs necessary address translations when in protected
mode. For data, there is a 64 KB 16-way set associative
writeback cache, and a 16-entry fully associative TLB.
When there is a miss to the instruction or data TLBs, there
is a second level unified (instruction and data) 64-entry 2way set associative TLB that takes an additional clock to
access. When there is a miss to the instruction or data
caches or the TLB, the access must go to the GeodeLink
Memory Controller (GLMC) for processing. Having both an
instruction and a data cache and their associated TLBs
improves overall efficiency of the integer unit by enabling
simultaneous access to both caches.
The L1 caches are supported by a 128 KB unified L2 victim
cache. The L2 cache can be configured to hold data,
instructions, or both. The L2 cache is 4-way set associative.
integer core. The datapath is optimized for single precision
arithmetic. Extended precision instructions are handled in
microcode and require multiple passes through the pipeline. There is an execution pipeline and a load/store pipeline. This allows load/store operations to execute in parallel
with arithmetic instructions.
2.2GeodeLink™ Control Processor
The GeodeLink Control Processor (GLCP) is responsible
for reset control, macro clock management, and debug
support provided in the Geode LX processor. It contains
the JTAG interface and the scan chain control logic. It supports chip reset, including initial PLL control and programming and runtime power management macro clock control.
The JTAG support includes a TAP Controller that is IEEE
1149.1 compliant. CPU control can be obtained through
the JTAG interface into the TAP Controller, and all internal
registers, including CPU Core registers, can be accessed.
In-circuit emulation (ICE) capabilities are supported
through this JTAG and TAP Controller interface.
The GLCP also includes the companion device interface.
The companion device has several unique signals connected to this module that support Geode LX processor
reset, interrupts, and system power management.
2.3GeodeLink™ Interface Units
Together, the two GeodeLink Interface Units (GLIU0 and
GLIU1) make up the internal bus derived from the
GeodeLink architecture. GLIU0 connects five high bandwidth modules together with a seventh link to GLIU1 that
connects to the five low bandwidth modules.
2.4GeodeLink™ Memory Controller
The GeodeLink Memory Controller (GLMC) is the source
for all memory needs in a typical Geode LX processor system. The GLMC supports a memory data bus width of 64
bits and supports 200 MHz, 400 MT/S for DDR (Double
Data Rate).
2.1.4Bus Controller Unit
The bus controller unit provides a bridge from the processor to the GLIUs. When external memory access is
required, due to a cache miss, the physical address is
passed to the bus controller unit, that translates the cycle
to a GeodeLink cycle.
2.1.5Floating Point Unit
The Floating Point Unit (FPU) is a pipelined arithmetic unit
that performs floating point operations as per the IEEE 754
standard. The instruction sets supported are x87, MMX,
and AMD 3DNow! technology. The FPU is a pipelined
machine with dynamic scheduling of instructions to minimize stalls due to data dependencies. It performs out of
order execution and register renaming. It is designed to
support an instruction issue rate of one per clock from the
16AMD Geode™ LX Processors Data Book
The modules that need memory are the CPU Core, Graphics Processor, Display Controller, Video Input Port, and
Security Block. Because the GLMC supports memory
needs for both the CPU Core and the display subsystem,
the GLMC is classically called a UMA (Unified Memory
Architecture) subsystem. PCI accesses to main memory
are also supported.
Up to four banks, with eight devices maximum in each bank
of SDRAM, are supported with up to 512 MB in each bank.
Four banks means that one or two DIMM or SODIMM modules can be used in a AMD Geode LX processor system.
Some memory configurations have additional restrictions
on maximum device quantity.
Architecture Overview
33234H
2.5Graphics Processor
The Graphics Processor is based on the graphics processor used in the AMD Geode GX processor with several features added to enhance performance and functionality. Like
its predecessor, the AMD Geode LX processor’s Graphics
Processor is a BitBLT/vector engine that supports pattern
generation, source expansion, pattern/source transparency, 256 ternary raster operations, alpha blenders to support alpha-BLTs, incorporated BLT FIFOs, a GeodeLink
interface and the ability to throttle BLTs according to video
timing. Features added to the Graphics Processor include:
• Command buffer interface
• Hardware accelerated rotation BLTs
• Color depth conversion
• Paletized color
• Full 8x8 color pattern buffer
• Channel 3 - third DMA channel
• Monochrome inversion
Table 2-1 presents a comparison between the Graphics
Processor features of the AMD Geode GX and LX processors.
Color Depth ConversionNo5:6:5, 1:5:5:5, 4:4:4:4, 8:8:8:8
Ye sYe s
8x2 (16 pixels)
8x4 (8 pixels)
AMD Geode™ LX Processors Data Book 17
33234H
Architecture Overview
2.6Display Controller
The Display Controller performs the following functions:
1) Retrieves graphics, video, and cursor data.
2) Serializes the streams.
3) Performs any necessary color lookups and output for-
matting.
4) Interfaces to the Video Processor for driving the dis-
play device(s).
The Display Controller consists of a memory retrieval system for rasterized graphics data, a VGA, and a back-end filter. The AMD Geode LX processor’s Display Controller
corresponds to the Display Controller function found in the
AMD Geode GX processor with additional hardware for
graphics filter functions. The VGA provides full hardware
compatibility with the VGA graphics standard. The rasterized graphics and the VGA share a single display FIFO and
display refresh memory interface to the GeodeLink Memory Controller (GLMC). The VGA uses 8 bpp and syncs,
that are expanded to 24 bpp via the color lookup table, and
passes the information to the graphics filter for scaling and
interlaced display support. The stream is then passed to
the Video Processor, which is used for video overlay. The
Video Processor forwards this information to the DAC (Digital-to-Analog Converter), that generates the analog red,
green, and blue signals, and buffers the sync signals that
are then sent to the display. The Video Processor output
can also be rendered as YUV data, and can be output on
the Video Output Port (VOP).
2.7Video Processor
The Video Processor mixes the graphics and video
streams, and outputs either digital RGB data to the internal
DACs or the flat panel interface, or digital YUV data via the
VOP interface.
The Video Processor delivers high-resolution and truecolor graphics. It can also overlay or blend a scaled truecolor video image on the graphic background.
The Video Processor interfaces with the CPU Core via a
GLIU master/slave interface. The Video Processor is a
slave only, as it has no memory requirements.
2.7.2TFT Controller
The TFT Controller converts the digital RGB output of a
Video Mixer block to the digital output suitable for driving a
TFT flat panel LCD.
The flat panel connects to the RGB port of the Video Mixer.
It interfaces directly to industry standard 18-bit or 24-bit
active matrix thin film transistor (TFT). The digital RGB or
video data that is supplied by the video logic is converted
into a suitable format to drive a wide range of panels with
variable bits. The LCD interface includes dithering logic to
increase the apparent number of colors displayed for use
on panels with less than 6 bits per color. The LCD interface
also supports automatic power sequencing of panel power
supplies.
It supports panels up to a 24-bit interface and up to
1600x1200 resolution.
The TFT Controller interfaces with the CPU Core via a
GLIU master/slave interface. The TFT Controller is both a
GLIU master and slave.
2.7.3Video Output Port
The VOP receives YUV 4:4:4 encoded data from the Video
Processor and formats the data into a video stream that is
BT.656 compliant. Output from the VOP goes to either a
VIP or a TV encoder. The VOP is BT.656/601 compliant
since its output may go directly (or indirectly) to a display.
2.8Video Input Port
The Video Input Port (VIP) receives 8- or 16-bit video or
ancillary data, 8-bit message data, or 8-bit raw video and
passes it to data buffers located in system memory. The
VIP is a DMA engine. The primary operational mode is as a
compliant VESA 2.0 slave. The VESA 2.0 specification
defines the protocol for receiving video, VBI, and ancillary
data. The addition of the message passing and data
streaming modes provides additional flexibility in receiving
non-VESA 2.0 compliant data streams. Input data is
packed into QWORDS, buffered into a FIFO, and sent to
system memory over the GLIU. The VIP masters the internal GLIU and transfers the data from the FIFO to system
memory. The maximum input data rate (8- or 16-bits) is 150
MHz.
2.7.1CRT Interface
The internal high performance DACs support CRT resolutions up to:
— 1920x1440x32 bpp at 85 Hz
— 1600x1200x32 bpp at 100 Hz
18AMD Geode™ LX Processors Data Book
2.9GeodeLink™ PCI Bridge
The GeodeLink PCI Bridge (GLPCI) contains all the necessary logic to support an external PCI interface. The PCI
interface is PCI v2.2 specification compliant. The logic
includes the PCI and GLIU interface control, read and write
FIFOs, and a PCI arbiter.
Architecture Overview
33234H
2.10Security Block
The AMD Geode LX processor has an on-chip AES 128-bit
crypto acceleration block capable of 44 Mbps throughput
on either encryption or decryption at a processor speed of
500 MHz. The AES block runs asynchronously to the processor core and is DMA based. The AES block supports
both EBC and CBC modes and has an interface for
accessing the optional EEPROM memory for storing
unique IDs and/or security keys. The AES and EEPROM
sections have separate control registers but share a single
set of interrupt registers. The AES module has two key
sources: one hidden 128-bit key stored in the “on-package”
EEPROM, and a write only 128-bit key (reads as all zeros).
The hidden key is loaded automatically by the hardware
after reset and is not visible to the processor. The
EEPROM can be locked. The initialization vector for the
CBC mode can be generated by the True Random Number
Generator (TRNG). The TRNG is addressable separately
and generates a 32-bit random number.
AMD Geode™ LX Processors Data Book 19
33234H
Architecture Overview
20AMD Geode™ LX Processors Data Book
Signal Definitions33234H
3.0Signal Definitions
3
This chapter defines the signals and describes the external interface of the AMD Geode™ LX processor. Figure 3-1 shows
the pins organized by their functional groupings. Where signals are multiplexed, the default signal name is listed first and is
separated by a plus sign (+). Multi-function pins are described in Table 3-1 on page 22.
Note 1.Alpha RED/GREEN/BLUE: Useful for off-chip graphics digital interfaces.
Note 2.Pin usage depends on TFT mode. See Section 6.7.7 "Flat Panel Display Controller" on page 405 for details.
RGB w/16-bit
VIP
ARGB (Note 1)
w/8-bit VIP
TFT w/16-bit VIP
(not 601)
8- or 16-bit VOP
w/16-bit VIP
22AMD Geode™ LX Processors Data Book
Signal Definitions
33234H
3.1Buffer Types
The Ball Assignment tables starting on page 26 include a
column labeled “Buffer Type”. The details of each buffer
type listed in this column are given in Table 3-2. The column headings in Table 3-2 are identified as follows:
TS: Indicates whether the buffer may be put into the TRISTATE mode. Note some pins that have buffer types that
allow TRI-STATE may never actually enter the TRI-STATE
mode in practice, since they may be inputs or provide other
signals that are always driven. To determine if a particular
signal can be put in the TRI-STATE mode, consult the individual signal descriptions in Section 3.4 "Signal Descriptions" on page 33.
OD: Indicates if the buffer is open-drain, or not. Open-drain
outputs may be wire ORed together and require a discrete
pull-up resistor to operate properly.
5VT: Indicates if the buffer is 5-volt tolerant, or not. If it is 5volt tolerant, then 5 volt TTL signals may be safely applied
to this pin.
PU/PD: Indicates if an internal, programmable pull-up or
pull-down resistor may be present.
Current High/Low (mA): This column gives the current
source/sink capacities when the voltage at the pin is high,
and low. The high and low values are separated by a “/”
and values given are in milli-amps (mA).
Rise/Fall @ Load: This column indicates the rise and fall
times for the different buffer types at the load capacitance
indicated. These measurements are given in two ways:
rise/fall time between the 20%-80% voltage levels, or, the
rate of change the buffer is capable of, in volts-per-nanosecond (V/ns).
Note the presence of “Wire” type buffer in this table. Signals identified as a wire-type are not driven by a buffer,
hence no rise/fall time or other measurements are given;
these are marked “NA” in Table 3-2. The wire-type connection indicates a direct connection to internal circuits such
as power, ground, and analog signals.
Table 3-2. Buffer Type Characteristics
NameTSOD5VTPU/PD
Current
High/Low
(mA)Rise/Fall @ Load
24/Q3XX24/243 ns @ 50 pF
24/Q5XX24/245 ns @ 50 pF
24/Q7XX24/247 ns @ 50 pF
5VXX16/161.25V/ns @ 40 pF
PCIX0.5/1.51-4V/ns @ 10 pF
DDRCLK10/108.5V/ns @ 15 pF
DDR 2.4V/ns @ 50 pF
WireNANANANANA
AMD Geode™ LX Processors Data Book 23
33234H
Signal Definitions
3.2Bootstrap Options
The bootstrap options shown in Table 3-3 are supported in
the AMD Geode LX processor for configuring the system.
Table 3-3. Bootstrap Options
PinsDescription
IRQ130: Normal boot operation, TAP reset
active during PCI reset
1: Debug stall of CPU after CPU
reset, TAP reset active until V
PW10: PCI (SYSREF) is 33 MHz
1: PCI (SYSREF) is 66 MHz
PW0,
SUSPA#,
GNT[2:0]#
Select CPU and GeodeLink system
MHz options including a PLL bypass
option. Refer to Table 6-87 on page
556 for programming.
IO
valid
3.3Ball Assignments
The tables in this chapter use several common abbreviations. Table 3-4 lists the mnemonics and their meanings.
Table 3-4. Ball Type Definitions
MnemonicDefinition
AAnalog
IInput ball
I/OBidirectional ball
CAV
SS
CAV
DD
DAV
SS
DAV
DD
MAV
SS
MAV
DD
OOutput ball
VAV
SS
VAV
DD
V
CORE
V
IO
V
MEM
V
SS
#The “#” symbol at the end of a signal
Core PLL Ground ball: Analog
Core PLL Power ball: Analog
DAC PLL Ground ball: Analog
DAC PLL Power ball: Analog
GLIU PLL Ground ball: Analog
GLIU PLL Power ball: Analog
Video PLL Ground ball: Analog
Video PLL Power ball: Analog
Power ball: 1.2V (Nominal)
I/O Power ball: 3.3V (Nominal)
Power ball: 2.5V
Ground ball
name indicates that the active, or
asserted state, occurs when the signal is at a low voltage level. When “#”
is not present after the signal name,
the signal is asserted when at a high
voltage level.