The most common bus in the PC world, ISA stands for Industry Standard Architecture, and different many uses of the word "standard", in this case it in fact fits. The ISA bus is still a foundation in even the latest computers, despite the fact that it is mainly unchanged since it was prolonged to 16 bits in 1984! The ISA bus finally became a bottleneck to performance and was augmented with extra high-speed buses, but ISA persists because of the truly huge base of obtainable peripherals using the standard. Also, there are still many devices for which the ISA's speed is more than enough, and will be for a number of times to come
The choices made in important the main characteristics of the ISA bus--its width and speed--can be seen by looking at the processors with which it was balancing on early machines. The unique ISA bus on the IBM PC was 8 bits wide, shiny the 8 bit data width of the Intel 8088 processor's system bus, and ran at 4.77 MHz, again, the speed of the first 8088s. In 1984 the IBM AT was introduced using the Intel 80286; at the moment the bus was doubled to 16 bits (the 80286's data bus width) and increased to 8 MHz (the maximum speed of the original AT, which came in 6 MHz and 8 MHz versions).
The choices made in important the main characteristics of the ISA bus--its width and speed--can be seen by looking at the processors with which it was balancing on early machines. The unique ISA bus on the IBM PC was 8 bits wide, shiny the 8 bit data width of the Intel 8088 processor's system bus, and ran at 4.77 MHz, again, the speed of the first 8088s. In 1984 the IBM AT was introduced using the Intel 80286; at the moment the bus was doubled to 16 bits (the 80286's data bus width) and increased to 8 MHz (the maximum speed of the original AT, which came in 6 MHz and 8 MHz versions).
No comments:
Post a Comment