Ampro Corporation 486E - Manual (Page 21)

Product Reference
2–5
Table 2–3. Little Board/486e I/O Map
I/O Address Function
3F8h - 3FFh Primary serial port
3F2h - 3F7h
Floppy disk controller ports
3F2: FDC Digital output register
3F4: FDC Main status register
3F5: FDC Data register
3F7: FDC Control register
3F0h - 3F1h Ampro reserved
3E8h - 3EFh Third serial port
3D0h - 3D7h, 3DA Video controller
3C0h - 3CFh Video controller
3B4, 3B5, 3BA Video controller (MDA Emulation)
378h - 37Fh Primary parallel printer port
320h - 32Fh Ethernet interface (default)
2F8h - 2FFh Secondary serial port
2F0h - 2F3h Ampro reserved
2E8h - 2EFh Fourth serial port
278h - 27Fh Secondary parallel printer port
1F8h - 1FFh Ampro reserved
1F0h - 1F7h IDE hard disk interface
102 Video Controller (Global Enable)
0F0h - 0FFh Reserved
0C0h - 0DFh DMA controller 2 (8237 equivalent)
0A0h - 0A1h Interrupt controller 2 (8359 equivalent)
092h Fast A20 gate and CPU reset
080h - 08Fh DMA page registers (74LS61 equivalent)
070h - 071h Real-time clock and NMI mask
060h, 064h Keyboard controller (8042 equivalent)
040h - 043h Programmable timer (8254 equivalent)
020h - 021h Interrupt controller 1 (8359 equivalent)
000h - 00Fh DMA controller 1 (8237 equivalent)
E0E0h - E0EFh Ethernet disable address (full 16-bit address)
Note
All I/O ports below 100h are reserved for internal system functions
and should not be accessed.