|
|
Typical device DMA channels |
|
Device type |
Typical dma |
| SCSI | 3,5 |
| Sound Card | 1,5,7 |
| Network Card | 1,3,5,7 |
PC/XT Device Addresses |
|
I/O Address |
Description |
| 000-01Fh | DMA Controller - Channels 0-3 |
| 020h-021h | Interrupt Controllers |
| 040-043h | System Timers |
| 060h | Keyboard, Aux. |
| 070h-071h | Real Time Clock / CMOS, NMI Mask |
| 081-083h & 087h | DMA Page Register (0-3) |
| 0F0-0FFh | Math Coprocessor |
| 108-12Fh | Not Assigned; Reserved by/for IBM use |
| 130-13Fh | Not Assigned; Reserved by/for IBM use |
| 140-14Fh | Not Assigned; Reserved by/for IBM use |
| 150-1Efh | Not Assigned; Reserved by/for IBM use |
| 200-207h | Game Port |
| 208-20Bh | Not Assigned |
| 20C-20Dh | Reserved |
| 20E-21E | Not Assigned |
| 21F | Reserved |
| 220-22xh | Not Assigned |
| 230-23xh | Not Assigned |
| 240-247h | Not Assigned |
| 250-277h | Not Assigned |
| 278-27Fh | LPT 2 or LPT 3 -- 3rd Parallel I/O Port |
| 280-2Afh | Not Assigned |
| 2B0-2Dfh | Alternative EGA Port |
| 2E1h | GPIB 0 |
| 2E2h & 2E3h | Data Acq 0 |
| 2E4--2E7h | Not Assigned |
| 2E8-2Efh | COM 4 -- 4th Serial I/O Port |
| 2F8-2FFh | COM 2 -- 2nd Serial I/O Port |
| 300-31Fh | IBM Prototype Card |
| 320-323h | Primary PC/XT Hard Disk Adapter |
| 324-327h | Secondary PC/XT Hard Disk Adapter |
| 328-32Fh | Not Assigned |
| 330-33Fh | Not Assigned |
| 340-34Fh | Not Assigned |
| 350-35Fh | Not Assigned |
| 360-363h | PC Network Card -- Low I/O Port |
| 364-367h | Reserved |
| 368-36Ah | PC Network Card -- HighI/O Port |
| 36C-36Fh | Reserved |
| 370-377h | Secondary Diskette Drive Adapter |
| 378-37Fh | LPT 2 or LPT 1 -- 1st or 2nd Parallel I/O Port |
| 380-389h | Not Assigned |
| 380-38Ch | BISYNC_1 or SDLC_2 |
| 390-393h | Cluster Adapter |
| 394-3A9h | Not Assigned |
| 3A0-3ACh | BISYNC_2 or SDLC_1 |
| 3B0-3BFh | Monochrome Video Adapter |
| 3BC-3BFh | 1st Parallel I/O Port -- Part of Monochrome Video Card |
| 3C0-3CFh | EGA Video |
| 3D0-3DFh | CGA Video |
| 3E0-3E7h | Not Assigned |
| 3E8-3EFh | COM3 -- 3rd Serial I/O Port |
| 3F0-3F7h | Primary Diskette Drive Adapter |
| 3F8-3FFh | COM1 -- 1st Serial I/O Port |
DMA Channels |
|
BIOS Address |
USE |
| C000-C7FF | Color video adapters (32k) |
| C800-CFFF | Hard disk controller or SCSI (32k) |
| C800-CFFF | SCSI Host Adapter BIOS (32k) |
| D000-D7FF | SCSI Host Adapter BIOS (32k) |
| D800-DFFF | SCSI Host Adapter BIOS (32k) |
| E000-E7FF | SCSI Host Adapter BIOS (32k) |
| E800-EFFF | SCSI Host Adapter BIOS (32k) |
| E000-EFFF | LIMS EMS Memory Page Frame (64k) |
IRO Assignments |
||
IRQ |
PC/XT |
AT's on up |
| 0 | System Timer | System Timer |
| 1 | Keyboard Controller | Keyboard Controller |
| 2 | Not Assigned | Tied to IRQs 8-15 |
| 3 | COM2 : 2F8h-2FFh | COM2: 2F8h-2FFh |
| 4 | COM1: 3F8h-3FFh | COM1: 3F8h-3FFh |
| 5 | XT HD Controller | LPT2: 378h or 278h |
| 6 | Diskette Controller | Diskette Controller |
| 7 | LPT1: 3BCh or 378H | LPT1: 3BCh or 378h |
| 8 | Not Avalible on PC or XT | Real Time Clock |
| 9 | Not Avalible on PC or XT | Substutes for IRQ 2 |
| 10 | Not Avalible on PC or XT | Not Assigned |
| 11 | Not Avalible on PC or XT | Not Assigned |
| 12 | Not Avalible on PC or XT | PS/2 Mouse Port |
| 13 | Not Avalible on PC or XT | NPU (Math Coprocessor) |
| 14 | Not Avalible on PC or XT | Hard Disk |
| 15 | Not Avalible on PC or XT | 2nd Hard Disk Adapter |