Personal Computer Memory Card International Association Standardizes packages for memory and input/output (modems, LAN cards, etc.) for computers, laptops, palmtops, etc. For each there is a specific set for each bus to use. As a bus it is the network/or circuitry's placement in which all the devices are attached to it and all signals pass through each device, but only the targeted device will receive and recognize the signal intended for it. The PCMCIA bus is 8 bits wide and doesn't allow for direct memory access (DMA) transfers, or bus mastering. The newest version called the CardBus addresses these issues.
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