Dell Inspiron 3800 System Reference Manual page 11

Technical Overview: Dell Inspiron 3800 System Reference
IRQ3 Available for use by a PC Card unless the integrated serial port or infrared port is configured for COM2 or COM4
IRQ4 Available for use by a PC Card unless the integrated serial port or infrared port is configured for COM1 (the default) or
COM3
IRQ5 Available for use by the audio controller
IRQ6 Generated by the diskette drive controller to indicate that the diskette drive requires the attention of the microprocessor
IRQ7 Available for use by a PC Card or audio controller if the parallel port is disabled
IRQ8 Reserved; generated by the system input/output (I/O) controller's real-time clock (RTC)
IRQ9 Reserved; generated by the video controller
IRQ10 Available for use by a PC Card or audio controller unless the APR is attached
IRQ11 Generated by USB, PC Card, and audio controllers; available for use by a PC Card
IRQ12 Reserved; generated by the keyboard controller to indicate that the output buffer of the DualPoint integrated pointing device
or the external PS/2 mouse is full
IRQ13 Reserved; generated by the math coprocessor
IRQ14 Reserved; generated by the hard-disk drive to indicate that the drive requires the attention of the microprocessor
IRQ15 Reserved; generated by the CD-ROM drive in the media bay to indicate that the drive requires the attention of the
microprocessor
Memory
Memory Allocations
Table 4 provides a map of the conventional memory area. When the microprocessor or a program addresses a location within the
conventional memory range, it is physically addressing a location in main memory.
To view memory allocations in Windows 98, click the Start button, point to Settings, and click Control Panel. Double-click the System
icon. Click the Device Manager tab, and then double-click Computer.
To view memory allocations in Windows NT, start the Windows NT Diagnostics in the Administrative Tools (Common) folder.
To view memory allocations in Windows 2000, click the Start button, point to Settings, and click Control Panel. Double-click the System
icon. Click the Hardware tab, and then click Device Manager.
Table 4. Conventional Memory Map
Address Range
0000h-003FFh
00400h-00FFFF
00500h-005FFh
00600h-9FBFFh
Table 5 provides a map of the upper memory area. Some of these addresses are dedicated to various system devices, such as the
system/video basic input/output system (BIOS). Others are available for use by expansion cards and/or an expanded memory manager
(EMM).
When the microprocessor or a program addresses a location within the upper memory area, it is physically addressing a location within
one of these devices.
file:///F|/Service%20Manuals/Dell/Inspiron/3800/overview.htm (8 of 10) [2/28/2004 6:58:48 AM]
Use
Interrupt vector table
BIOS data area
MS-DOS® and BASIC work area
User memory