Acronyms and Abbreviations

F

FPGA (Field Programmable Gate Array) A type of gate array that is programmed in the field rather than in a semiconductor fabrication facility. Containing up to hundreds of thousands of gates, there are a variety of FPGA architectures on the market. Some are very sophisticated, including not only programmable logic blocks, but programmable interconnects and switches between the blocks. The interconnects take up a lot of FPGA real estate, resulting in a chip with very low gate density compared to other technologies.

H

HDD (Hard Disk Drive) The primary computer storage medium, made of one or more aluminum or glass platters, coated with a ferromagnetic material. Most hard disks are “fixed disks,” which have platters that reside permanently in the drive.

I

I/O (Input/Output) Transferring data between the CPU and a peripheral device. Every transfer is an output from one device and an input into another.

IDE (Integrated Drive Electronics) A type of hardware interface widely used to connect hard disks, CD-ROMs and tape drives to a PC. IDE was always the more economical interface, compared to SCSI. Starting out with 40MB capacities years ago, 20GB IDE hard disks have become entry level, costing a fraction of a cent per megabyte.

IO (Input/Output; see I/O)

L

LBA (Logical Block Addressing) A method used to support IDE hard disks larger than 504MB (528,482,304 bytes) on PCs. LBA provides the necessary address conversion in the BIOS to support drives up to 8GB. BIOS after mid-1994, which are sometimes called “Enhanced BIOS,” generally provide LBA conversion. LBA support is required for compatibility with the FAT32 directory.

LSB (Least Significant Byte) “Byte” defines a sequence of 8-bits, with the right-most bit being the least significant and the left-most bit being the most- significant.

LSW (Least Significant Word) “Word” denotes sequence of 4 bytes, or 32 bits, with the left-most being the least significant, and the right-most being the most significant. “Double-word” denotes sequence of two words, or 64bits, with the left most word being the least significant, and the right-most - the most significant. Note, that the definition of “word” defines a little-endian scheme, so for big- endian platforms, or network applications, special steps need to be taken to reorder the bytes form the input stream.

M

MLC (Multi-Level Cell) A flash memory technology that stores more than one bit of data per cell. Traditional flash memory defines a 0 or 1 bit, based on a single voltage threshold. The patterns of two bits (0-0, 0-1, 1-0, and 1-1) can be achieved with four voltage levels and eight levels of voltage can yield all the combinations in three bits.

MSB (Most Significant) “byte” defines a sequence of 8-bits, with the right-most bit being the least significant and the left-most bit being the most- significant.

MSW (Most Significant Word) “Word” denotes sequence of 4 bytes, or 32 bits, with the left-most being the least significant, and the right-most being the most significant. “Double-word” denotes sequence of two words, or 64bits, with the left most word being the least significant, and the right-most - the most significant. Note, that the definition of “word” defines a little-endian scheme, so for big- endian platforms, or network applications, special steps need to be taken to reorder the bytes form the input stream.

N

NAND (Not AND) A Boolean logic operation that is true if any single input is false. Two-input NAND gates are often used as the sole logic element on gate array chips, because all Boolean operations can be created from NAND gates.

P

PIO (Programmed Input/Output) The data transfer mode used by IDE drives. PIO modes use the CPU’s registers for data transfer in contrast with DMA, which transfers directly between main memory and the peripheral device.

34

Zeus Ultra DMA Solid State Drives