B&B Electronics 3PXCC4A manual 3BC-3BE

Hex Address

000-01F

020-03F

040-05F

060-06F

070-07F

080-09F

0A0-0BF

0C0-0DF

0F0-0FF

1F0-1F8

200-20F

258-25F

278-27F

2E8-2EF

2F8-2FF

300-31F

378-37F

380-38F

3A0-3AF

3B0-3BF

3BC-3BE

3C0-3CF

3D0-3D7

3E8-3EF

3F0-3F7

3F8-3FF

I/O Map of AT Class Machines

Address Function in AT Class Machines

DMA controller #1 (8237A-5)

interrupt controller #1 (8259A)

timer (8254)

keyboard (8042)

NMI - non maskable interrupt & CMOS RAM

DMA page register (74LS612)

interrupt controller #2 (8259A)

DMA controller #2 (8237A)

80287 math coprocessor

hard disk

game port joystick controller

Intel Above Board

parallel printer port 2

COM4 serial port

COM2 serial port

prototype card

parallel printer 1

SDLC or bisync com 2

bisync com 1

MDA - monochrome adapter

parallel printer on monochrome adapter

EGA - reserved

CGA - color graphics adapter

COM 3 serial port

floppy diskette controller

COM1 serial port

Any eight-byte space not used by one of the devices listed in the table and not used by any other equipment in your system may be used for the serial port.

A-2 Appendix A: Hardware I/O Manual Document# 3PXCC4A3001

B&B Electronics Mfg Co – 707 Dayton Rd - PO Box 1040 - Ottawa IL 61350 - Ph 815-433-5100 - Fax 815-433-5104 B&B Electronics Ltd – Westlink Comm. Pk – Oranmore, Galway, Ireland – Ph +353 91-792444 – Fax +353 91-792445