Appendix B. System address maps

Figure

34

(Page 3 of

 

3). I/O address map

 

 

 

 

 

 

 

 

 

 

Address

(Hex)

 

Size

 

 

Description

 

 

 

 

 

 

 

0480–048F

 

 

16

bytes

DMA channel high page registers

 

 

 

 

 

 

 

0490–0CF7

 

 

1912

bytes

Available

 

 

 

 

 

 

 

 

 

0CF8–0CFB

 

 

4

bytes

PCI

Configuration

address register

 

 

 

 

 

 

 

 

 

0CFC–0CFF

 

 

 

4

bytes

PCI

Configuration

data register

 

 

 

 

 

 

 

LPT n

+

400h

 

8 bytes

ECP

port, LPTn base address+ hex 400

 

 

 

 

 

 

 

0CF9

 

 

 

1

byte

Turbo and reset control register

 

 

 

 

 

 

 

0D00–FFFF

 

 

62207

bytes

Available

 

 

 

 

 

 

 

 

 

 

 

DMA

I/O

address

map

 

 

 

 

 

 

 

 

 

 

 

The

following figure

lists

resource

assignments

for

the DMA

address map. Any addresses

shown

are

reserved.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Figure

35

(Page

1

of

2).

DMA I/O address map

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Address (Hex)

 

Description

 

 

 

 

 

 

Bits

 

Byte

pointer

 

 

 

 

 

 

 

 

 

 

 

0000

 

 

 

Channel 0, Memory Address register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

0001

 

 

 

Channel 0, Transfer Count register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

0002

 

 

 

Channel 1, Memory Address register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

0003

 

 

 

Channel 1, Transfer Count register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

0004

 

 

 

Channel 2, Memory Address register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

0005

 

 

 

Channel 2, Transfer Count register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

0006

 

 

 

Channel 3, Memory Address register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

0007

 

 

 

Channel 3, Transfer Count register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

0008

 

 

 

Channels 0–3, Read Status/Write Command register00–07

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0009

 

 

 

Channels 0–3, Write Request register

00–02

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

000A

 

 

 

Channels 0–3, Write Single Mask

register bits 00–02

 

 

 

 

 

 

 

 

 

 

 

 

 

 

000B

 

 

 

Channels 0–3, Mode register (write)

00–07

 

 

 

 

 

 

 

 

 

 

 

 

 

 

000C

 

 

 

Channels 0–3, Clear byte pointer (write)

N/A

 

 

 

 

 

 

 

 

 

 

 

 

 

 

000D

 

 

 

Channels 0–3, Master clear (write)/temp (read)00–07

 

 

 

 

 

 

 

 

 

 

 

 

 

 

000E

 

 

 

Channels 0–3, Clear Mask register (write)

00–03

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

000F

 

 

 

Channels 0–3,

Write

All

Mask register bits

00–03

 

 

 

 

 

 

 

 

 

 

 

 

 

 

0081

 

 

 

Channel 2, Page Table Address 2register

00–07

 

 

 

 

0082

 

 

 

Channel 3, Page Table Address 2register

00–07

 

 

 

 

0083

 

 

 

Channel

1,

Page

Table

Address 2 register

00–07

 

 

 

 

0087

 

 

 

Channel

0,

Page

Table

Address

2

00–07

 

 

 

 

 

 

 

register

 

 

 

 

0089

 

 

 

Channel

6,

Page

Table

Address

2

00–07

 

 

 

 

 

 

 

register

 

 

 

 

008A

 

 

 

Channel

7,

Page

Table

Address

2

00–07

 

 

 

 

 

 

 

register

 

 

 

 

008B

 

 

 

 

 

 

 

 

 

 

2

00–07

 

 

 

 

 

 

 

Channel 5, Page Table Address register

 

 

 

 

008F

 

 

 

Channel 4, Page Table Address/Refresh register00–07

 

 

 

 

 

 

 

 

 

 

 

 

 

 

00C0

 

 

 

Channel 4, Memory Address register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

00C2

 

 

 

Channel 4, Transfer Count register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

00C4

 

 

 

Channel 5, Memory Address register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

00C6

 

 

 

Channel

5,

Transfer

Count register

00–15

 

Yes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

38 Technical Information Manual

Page 46
Image 46
IBM 6268, 6288, 6278 manual Are Reserved, DMA I/O address map, Bits Byte Pointer

6278, 6268, 6288 specifications

The IBM 6278, 6288, and 6268 are part of IBM's extensive lineup of mid-range computers, specifically tailored for business environments in the late 1980s and early 1990s. These systems were designed to handle substantial data processing tasks, facilitating efficient business operations with robust performance and reliability.

The IBM 6278 was notable for its high-performance capabilities, making it suitable for a variety of applications ranging from transaction processing to complex computations. One of the main features of the 6278 was its multiprocessing capability, which allowed it to run multiple tasks concurrently. This was achieved through a combination of advanced hardware and software that optimized performance and resource allocation.

Similarly, the IBM 6288 was recognized for its versatility and scalability. This system incorporated enhanced memory management and was capable of handling larger workloads than its predecessors. The 6288 was designed with user-friendly interfaces and supported various input/output devices, making it easier for organizations to integrate into existing IT infrastructures. Additionally, it provided improved connectivity options, essential for modern networking needs at the time.

The IBM 6268, on the other hand, offered a balance between cost and performance, appealing to smaller businesses or those with less intensive data processing requirements. Despite being less powerful than the 6278 and 6288, the 6268 still managed to include essential features such as reliable data storage, effective processing speed, and compatibility with IBM's extensive software ecosystem.

All three models utilized IBM's proprietary operating systems, which were well-known for their robustness and security features. They were built with technologies such as error detection and correction, ensuring the integrity of data processing tasks. The architecture of these systems also allowed for easy upgrades, enabling businesses to expand their capabilities without a complete overhaul of their IT infrastructure.

In summary, the IBM 6278, 6288, and 6268 represented a significant advancement in mid-range computing technology during their era. Their main features encompassed multiprocessing, scalability, and user-friendly interfaces, making them valuable assets for businesses seeking reliable and efficient computing solutions. These systems laid the groundwork for future innovations in business computing, and despite their age, they remain a significant part of IBM's legacy in the computing industry.