Dell Inspiron Lm Service Guide

System Overview 1-1
Chapter 1
System Overview
T
he Dell® Latitude® LM P-100SD and LM P-133ST are high-performance 
multimedia portable computers that use the Intel® Pentium® microprocessor. 
This chapter provides an overview of the components and subsystems of these 
computers. 
The individual model names within the Dell Latitude LM portable family indi-
cate the type and operating frequency of the microprocessor and display used in 
the computer. For example:
•The Dell Latitude LM P-100SD contains a...

1-2 Dell Latitude LM Systems Service Manual
warm swapping. However, the CD-ROM must be in the computer before or 
during boot in order for the drivers to load.
•Built-in serial infrared transmitter/receiver, effective to 1 m (3.3 ft).
•Support for connecting an external diskette drive to the parallel connector 
on the I/O panel.
Physical Description
Figure 1-1.  Front View of the Portable Computer
Figure 1-2.  Back View of the Portable Computer
LCD assembly
keyboard
 options bay 
 touch pad
latch (2)...

System Overview 1-3
Status Display
. 
Figure 1-3.  Status Display Panel
The status display panel is located directly above the keyboard. This panel 
shows icons that indicate keyboard operation or suspend mode; CD-ROM, 
hard-disk drive, diskette drive, and PC Card activity; and status of the power 
source (AC power or batteries). 
Keyboard Indicators
The following icons indicate the status of the keyboard and whether the com-
puter is in suspend mode.
Caps Lock Indicator
Press <
CAPS LOCK> to activate...

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Diskette-Drive Access Indicator
This indicator blinks when data is being transferred to or from the 
internal diskette drive.
PC Card Indicator
This indicator blinks when the computer is accessing data from an 
installed  PC Card or Cards.
AC Power Indicator
This indicator appears when the computer is receiving power through 
an AC power adapter. 
•If the icon is present but not blinking, the computer is on but the 
battery is not charging.
•If the icon is...

System Overview 1-5
Battery Charge Gauge 
There is a battery charge gauge on the main and second-
ary battery. When you press the battery test button 
(labeled “PUSH”), the appropriate indicator lights up for 
a few seconds to indicate the amount of charge remaining 
in the battery.
Password    
CAUTION:  Dell strongly recommends that the user back up the pass-
word onto a diskette. If the user forgets the password and does not have
it on diskette, the computer cannot be accessed. In that case, the com-...

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System Power
The power button controls power to the system. The computer receives power 
from either the AC adapter connected to an AC power source or from up to two 
batteries. If you use the AC adapter, constant power is available to the computer. 
If you use one or two batteries, the system has built-in power management fea-
tures that extend battery life by removing power from parts of the computer that 
are not being used.
Power Conservation...

System Overview 1-7
Interrupt Assignments
Table 1-1.  Interrupt Assignments
IRQ Line Used/Available
IRQ0 Generated by the system timer
IRQ1 Generated by the keyboard controller to signal that the key-
board output buffer is full
IRQ2 Cascade to second interrupt controller
IRQ3 Used by the infrared port (COM2)
IRQ4 Used by the serial port (COM1)
IRQ5 Used by the audio controller
IRQ6 Generated by the diskette drive controller to indicate that the 
diskette drive requires the attention of the...

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Technical Specifications 
Table 1-2.  Technical Specifications 
Microprocessor
Microprocessor type . . . . . . . .  Intel Pentium microprocessor
Microprocessor speed . . . . . . .  100 or 133 MHz
Internal cache memory . . . . . .  16 KB 
External cache  . . . . . . . . . . . .  256 KB
Math coprocessor . . . . . . . . . .  internal to the microprocessor
Chip Set and Bus
System chip set . . . . . . . . . . . .  Intel 430MX PCIset
Data bus width  . . . . . . . . ....

System Overview 1-9
Memory (Continued)
Memory access time:
tRAC   . . . . . . . . . . . . . . . .  70 ns
tCAC   . . . . . . . . . . . . . . . .  20 ns
BIOS address  . . . . . . . . . . . . .  F000:0000 
Connectors
Serial (DTE)  . . . . . . . . . . . . . .  one 9-pin connector; 16,550-compatible,  
16-byte buffer 
Parallel  . . . . . . . . . . . . . . . . . .  one 25-hole connector; unidirectional, 
bidirectional, EPP 1.9, or ECP
Monitor . . . . . . . . . . . . . . . . . .  one 15-hole connector
PS/2...

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Video
Video type. . . . . . . . . . . . . . . .  64-bit (128-bit hardware accelerated) PCI
Video controller  . . . . . . . . . . .  NeoMagic 2070
Video memory  . . . . . . . . . . . .  896 KB
Active-Matrix Display
Type  . . . . . . . . . . . . . . . . . . . .  active-matrix color (TFT)
Dimensions:
Height   . . . . . . . . . . . . . . .  184.5 mm (7.3 inches)
Width  . . . . . . . . . . . . . . . .  246.0 mm (9.7 inches)
Diagonal . . . . . . . . . . . . . ....