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13. Buses

A bus is not a vehicle used to carry a bunch of people; it is a connector to which devices are connected. A variety of different input/output buses exist on modern computers to connect things to them.

This includes such things as:

Generally speaking, the associations are that...

More wires associates with greater parallelism, greater speed, and greater complexity of device interfaces and requires that cabling remain short.

On the other side, serial buses tend to be slower, but allow interfacing to be simpler and for cables to be much longer.

Today's serial buses have more throughput than many of yesterday's parallel buses, but everything has gotten "souped up".

13.1. I2O

I2O was an I/O bus intended as an alternative to SCSI that would work in a highly buffered fashion, somewhat independently from the main "system" bus. This approach replicates what mainframe systems have long done, offloading as much I/O work as possible onto independent processors that manage the individual devices so that the main processor need not manage this.

While the general idea is very good, the standards were highly encumbered by NDAs (Non Disclosure Agreements) which hindered usage in conjunction with Linux. That was more than likely one of the reasons why the technology failed to attract wider interest. Nobody cares about I2O anymore...

13.2. USB - Universal Serial Bus

13.3. Modems, Serial Devices, Network Hardware

13.4. Miscellaneous Buses

13.5. Barcode Support

13.6. Disk Stuff

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