Base I/O Port Addresses for Most AT Intel Motherboards

000-00F         DMA CHANNEL 1
020-021         DMA CHANNEL 1
040-043         TIMER
060-063         Programmable Perfiheral Interface for XT
060-064         8742 Controller for AT
070-071         CMOS Ram for AT
080-08F         DMA Page Register
0A0-0A1         PIC #2 AT
0A0-0AF         NMI XT
0C0-0DF         DMA AT (Word Mapper)
0F0-0FF         286 Fpu
1F0-1FF         HDC AT
200-20F         Game Controller
210-21F         Expansion for XT
238-23B         Buss Mouse
23C-23F         Alt Buss Mouse
278-27F         LPT2
2B0-2BF         EGA
2C0-2CF         EGA
2D0-2DF         EGA
2E0-2E7         IEEE / GPIB  Buss
2E8-2EF         Comm 4
2F8-2FF         Comm 2
300-30F         Proto Type Card
300-31F         Proto Type Card
320-32F         HDC XT
378-37F         LPT1
380-38F         SDLC
3A0-3AF         SDLC
3B0-3BB         Monochrome Display Adapter
3BC-3BF         Monochrome Card Printer Port
3C0-3CF
3D0-3DF         CGA Adapter
3E8-3EF         Comm 3
3F0-3F7         Floppy Port
3F8-3FF         Comm 1