Compaq 615 manual System memory map specifications, System interrupt specifications

Specifications

System memory map specifications

	Size	Memory address	System function
	640 KB	00000000-0009FFFF	Base memory
	128 KB	000A0000-000BFFFF	Video memory
	64 KB	000C0000-000CFFFF	Video BIOS
	64 KB	000E8000-000FFFFF	System BIOS
		00100000- XFFFFFFF	Extended memory (based on
			memory installed)
		(X+1)0000000-FEDFFFFF	PCI bus
		FED00000-FED003FF	High precision event timer
		FEE01000-FFFFFFFF	PCI bus
System interrupt specifications

Hardware IRQ	System function
IRQ0	System timer
IRQ1	Standard 101-/102-key or Microsoft natural keyboard
IRQ8	System CMOS/real-time clock
IRQ12	Synaptics PS/2 TouchPad
IRQ13	Numeric data processor
IRQ16	Intel ICH9 family USB universal host controller 2937
	Mobile Intel 4 Series express chipset family
IRQ17*	High definition audio controller
	Intel ICH9 family USB universal host controller 2938
	Marvell Yukon 88E8072 PCIE-gigabit Ethernet controller
IRQ18	Intel ICH9 family USB universal host controller 2939
	Intel ICH9 family USB universal host controller 2936
IRQ19	Intel ICH9 family USB2 enhanced controller 293C
IRQ20	Intel ICH9 family USB2 enhanced controller 293A
	Intel ICH9 family USB universal host controller 2934
IRQ21	Intel ICH9M-E/M SATA AHCI controller
IRQ22	Intel ICH9 family USB universal host controller 2935

*Default configuration; audio possible configurations are IRQ5, IRQ7, IRQ9, IRQ10, or none.

✎PC Cards may assert IRQ3, IRQ4, IRQ5, IRQ7, IRQ9, IRQ10, IRQ11, or IRQ15. Either the infrared or the serial port may assert IRQ3 or IRQ4.

✎For operating systems after Windows 2000, APIC (Advanced programming interrupt controller) is used.

6–6 Maintenance and Service Guide