Ampro Corporation 486E manual Address Function

Product Reference

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

102Video 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.

2–5