Evolución de los buses de comunicación del ordenador compatible IBM PC
El bus de datos de un ordenador transfiere datos entre los componentes de una computadora.
El IBM PC comaptible ha evolucionado la conexión del bus de datos a medida que aumentaban las necesidades de velocidad de transferencia requeridos por los nuevos procesadores.
| Año | Arquitectura |
|---|---|
| 1981 | ISA (Industry Standard Architecture) 8 bits @ 4.7 MHz / 16 bits @ 8 MHz ISA debuting on the IBM PC AT, ISA was the evolution of the first PC bus in 1981. The 8-bit bus operates at 4.77 MHz (the same speed as the Intel 8088 processor used in the IBM PC), while the 16-bit bus operates at 8 MHz (the speed of the Intel 80286 in the IBM AT). It is also available on some non-IBM PC compatible machines, such as the AT&T Hobbit (which had a short history), the Commodore Amiga 2000, 3000 and 4000, as well as the BeBox based on PowerPC. |
| 1987 | MCA (Micro Channel) 32 bits @ 5 ~ 20 MHz IBM introduced Micro Channel with its PS/2 line in 1987, then later supported ISA. |
| 1989 | EISA 32 bits @ 8 ~ 10 MHz This ISA extension was created to counter Micro Channel, and EISA slots accepted ISA cards. Later abandoned for PCI. |
| 1992 | VL-bus (VESA Local) 32 bits @ 25 ~ 40 MHz The VL-bus was introduced during the 486 era and offered more speed than ISA. It too gave way to PCI. The VESA bus was created in 1992 with the advent of 32-bit microprocessors, by different manufacturers gathered in the Video Electronics Standard Association (VESA). Its bandwidth is 32 bits and later in the next version 2.0 it reached 64 bits. |
| 1997 | PCI (Peripheral Component Interconnect) 32 bits @ 33 or 66 MHz / 64 bits @ 33 or 66 MHz The first versions are more slow that VESA. Apple will adopt PCI for Power Macintosh (replacing NuBus) in mid-1995. |
| 1997 | AGP (Accelerated Graphics Port) 32 bits @ 66 ~ 533 MHz The graphics interface between PCI and PCI Express. AGP was faster than PCI and freed up a PCI slot. |
Durante años los dados en el bus circulaban en paralelo y sincronizados con el reloj del systema.
Actualmente las conexiones a los diferentes componentes se hace en serie, como en el caso del PCI Express.
