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I/o address map – IBM BDM-610000049 User Manual

Page 70

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60

CMX158886 cpuModule

BDM-610000049

Rev G

I/O Address Map

As with all standard PC/104 boards, the I/O total I/O space is 64k in size. However, because early processors only
addressed 0 address lines (SA0–SA9), the first 1k is used for legacy I/O devices. Any ISA add-on modules you
install must therefore use I/O addresses in the range of 0–1023 (decimal) or 000–3FF (hex). The upper I/O
addresses are used for PCI I/O devices, and are automatically assigned by the BIOS or operating system at boot
time.

Table 42 lists I/O addresses reserved for the CMX158886 cpuModule.

Note

If you add any PC/104 modules or other peripherals to the system you must ensure they do not use

reserved addresses listed below, or malfunctions will occur. The exception to this is if the resource has been
released by the user.

Table 42

I/O Addresses Reserved for the CMX158886 cpuModule

Address Range (hex)

Bytes

Device

000–00Fh

16

DMA Controller

010–01Fh

16

Reserved for CPU

020–021h

2

Interrupt Controller 1

022–02Fh

13

Reserved

040–043h

4

Timer

060–064h

5

Keyboard Interface

070–071h

2

Real Time Clock Port

080–08Fh

16

DMA Page Register

0A0–0A1h

2

Interrupt Controller 2

0C0–0DFh

32

DMA Controller 2

0F0–0FFh

16

Math Coprocessor

100–101h

2

Video Initialization

1F0–1FFh

16

Hard Disk

1

1. If a floppy or IDE controller is not connected to the system, the I/O addresses listed will not be occupied.

200–201h

2

Reserved

238–23Bh

4

Bus Mouse

2

2. If a PS/2 mouse is not connected to the system, the I/O addresses listed will not be occupied.

2E8–2EFh

8

Serial Port

3

3. The I/O addresses for the serial port are selected in the BIOS Setup utility.

2F8–2FFh

8

Serial Port

3

3E8–3EFh

8

Serial Port

3

3F0–3F7h

8

Floppy Disk

1

3F8–3FFh

8

Serial Port

3

450-454h

4

aDIO

4

4. If aDIO is disabled, the I/O addresses listed will not be occupied.

455h

1

Watchdog Timer

5

5. If watchdog timer is disabled, the I/O addresses listed will not be occupied.

456-45F

9

EPLD