CardBus

CardBus, the 32-bit high performance bus mastering architecture for PC Cards, was standardized by the PCMCIA in May 1996. This bus is targeted to mobile computers. PCI-like 32-bit interface operates at a power-saving 3.3 volts, and cards can include standardized power-management mechanisms. The CardBus interface allows an I/O adapter or a memory module to be added to or removed without disrupting the system"s operation. It adds high bandwidth PCI-based capabilities to the PC Card technology.

CardBus PC Cards are attached to their host system through a sturdy 68-pin connector, which is common to all PC Cards. (CardBus cards employ a shielding shroud around this connector, to enhance their signal integrity).

CardBus cards adopt the well-established PC Card form-factors. There are different types of CardBus cards (sizes are TxLxW):

• Type I: 3.3mm x 85.6mm x 54.0mm
• Type II: 5.0mm x 85.6mm x 54.0mm
• Type III: 10.5mm x 85.6mm x 54.0mm

CardBus provides a 32-bit multiplexed address/data path, which operates at PCI local-bus speeds of up to 33 MHz, yielding a peak bandwidth of 132MB/sec. CardBus accomplishes this by adopting the synchronous burst-transfer orientation of PCI, as well as a bus protocol, which is essentially identical to that of PCI.