Default x86 Port Address Assignments

Default x86 Port Address Assignments Address RangeFirst QWORDSecond QWORDThird QWORDFourth QWORD 0x000-0x00FDMA Controller Channels 0-3 0x010-0x01FSystem Use 0x020-0x02FInterrupt Controller 1System Use 0x030-0x03FSystem Use 0x040-0x04FSystem TimersSystem Use 0x050-0x05FSystem Use 0x060-0x06FKeyboard/PS2 Moude (Port 0x60) Speaker (0x61)Keyboard/PS2 Mouse (0x64)System Use 0x070-0x07FRTC/CMOS/NMI (0x70, 0x71)DMA Controller Channels 0-3 0x080-0x08FDMA Page Register 0-2 (0x81 - 0x83)DMA Page Register 3 (0x87)DMA Page Register 4-6 (0x89-0x8B)DMA Page Register 7 (0x8F) 0x090-0x09FSystem Use 0x0A0-0x0AFInterrupt Controller 2 (0xA0-0xA1)System Use 0x0B0-0x0BFSystem...

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HeLLo World Operating System Part 2

                                                  Bootloader So finally in this section we are going to build a small bootloader that will say helloworld on console. When a computer  starts up ( obviously by pressing the power button), the first thing that occurs is it  send a signal to motherboard which in turn starts the power supply. After supplying the correct amount of power to each device, it send a signal called "Power OK" to BIOS which resides on motherboard. Once the BIOS receive the "Power OK"...

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Hello World Operating System

So lets start making our little operating system and as tradition first we will make a hello world operating system.So things you should known before making operating system like what tool you gonna use,language,most important actually understanding what you are dealing with.."concepts". So what is Operating System??? An operating system (OS) is a set of programs that manage computer hardware resources and provide common services for application software.                                                      ...

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