Also known as Micro Channel Architecture (MCA), it was an earlier, proprietary 32-bit bus from IBM used in PS/2, RS/6000 and certain ES/9370 models. Micro Channel cards contained a unique ID that eliminated the error-prone task of setting DIP switches on ISA cards, the primary peripheral expansion of the era. MCA supported 15 levels of bus mastering and transferred data from 20 to 80MBytes/sec. In late 1996, IBM discontinued its use in favor of PCI. See PC data buses
Types of Expansion Cards
In the PC, Micro Channel, along with ISA, EISA, VL-bus and AGP, have disappeared. PCI and PCI Express buses become mainstream.