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Unformatted text preview: as 'PC-cards'. PDA Personal Digital Assistant; a term first coined to describe the Apple Newton, but now applied to any palmtop computer. PLA Programmable Logic Array; a pseudo-regular structure on an integrated circuit that implements a complex multi-output combinatorial logic function. PLL Phase-Locked Loop; a circuit used to generate a clock signal using another clock signal as a reference. PMOS P-type Metal Oxide Semiconductor, a semiconductor technology that pre-dates CMOS and NMOS that was used to build early 4-bit microprocessors. It supports a logic family with active pull-up and passive pull-down outputs, and gates with a high output draw current even when not switching. PMOS transistors are used, with NMOS transistors, to form CMOS. PSR Program Status Register, the register in a processor that holds various bits of information such as the condition codes, the interrupt disable bits and the operating mode bits. The ARM has a CPSR (Current Program Status Register), and an SPSR (Saved Program Status Register) for each non-user mode. PSU Power Supply Unit; the electronics that provides the regulated supply voltage(s) required by the system, usually using a mains electricity or battery power source. RAM Random Access Memory; a misnomer, since ROM is also random access, RAM is used to refer to the read- write memory used to store programs and data in a computer; the term is also used to describe the semiconductor components used to build this memory and also used in structures such as caches and TLBs. RISC Reduced Instruction Set Computer; a processor with an architecture with certain characteristics based on ideas expounded around 1980 by Patterson (U.C. Berkeley), Ditzel (Bell Laboratories) and Hennessy (Stanford University). ROM Read Only Memory; the fixed program store in a computer, also used to describe the semiconductor devices which may be used in this role. Contrast with RAM. RS232 A particular standard for asynchronous serial communications, enabling the connection of modems, printers, and communication with other machines. RTC Real-Time Clock; a clock source which allows a computer to wor...
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This document was uploaded on 10/30/2011 for the course CSE 378 380 at SUNY Buffalo.
- Spring '09