Micro Channel architecture: Difference between revisions

Revision as of 07:55, 18 September 2005

Revision as of 08:01, 18 September 2005

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Most of the problems were not a big issue in the early days of DOS, but came to the surface as the range of tasks and peripherals grew.

Other=== ISA design issues<br> ===

Another problem for the IBM designers was that the original ISA bus design was deeply linked to the [[Central processing unit|CPU]] architecture of the 80x86 chip family, principally the

* [[Intel 8088]]

* [[Intel 8086]]

* [[Intel 80286]]

[[Central processing unit|CPU]] architecture.

Cards built for ISA would simply not work in any other machine. IBM was already investigating the use of [[RISC]] processors in desktop machines, and could, in theory, save considerable money if a single bus could be used across their entire computer lineup.

IBM was already investigating the use of [[RISC]] processors in desktop machines, and could, in theory, save considerable money if a single bus could be used across their entire computer lineup.

Marketshare<br>

=== Marketshare<br> issues ===

A final problem was that IBM had lost control of the hardware market for PCs. Anyone could create an ISA card and plug it into anyone's computer. By creating a new standard IBM would regain control, and this time the specifications would require licensing. This largely explains why they created MCA, as opposed to selecting an existing standard like [[NuBus]] which would have saved them a lot of time and money.