Low Pin Count
Overview
IBM PC compatible
IBM PC compatible computers are those generally similar to the original IBM PC, XT, and AT. Such computers used to be referred to as PC clones, or IBM clones since they almost exactly duplicated all the significant features of the PC architecture, facilitated by various manufacturers' ability to...
personal computer
Personal computer
A personal computer is any general-purpose computer whose size, capabilities, and original sales price make it useful for individuals, and which is intended to be operated directly by an end-user with no intervening computer operator...
s to connect low-bandwidth devices to the CPU
Central processing unit
The central processing unit is the portion of a computer system that carries out the instructions of a computer program, to perform the basic arithmetical, logical, and input/output operations of the system. The CPU plays a role somewhat analogous to the brain in the computer. The term has been in...
, such as the boot ROM
BIOS
In IBM PC compatible computers, the basic input/output system , also known as the System BIOS or ROM BIOS , is a de facto standard defining a firmware interface....
and the "legacy" I/O devices (behind a super I/O
Super I/O
Super I/O is a class of I/O controller integrated circuits that began to be used on personal computer motherboards in the late 1980s, originally as add-in cards, later embedded on the motherboards. A super I/O chip combines interfaces for a variety of low-bandwidth devices...
chip). The "legacy" I/O devices usually include serial
Serial port
In computing, a serial port is a serial communication physical interface through which information transfers in or out one bit at a time...
and parallel
Parallel port
A parallel port is a type of interface found on computers for connecting various peripherals. In computing, a parallel port is a parallel communication physical interface. It is also known as a printer port or Centronics port...
ports, PS/2
PS/2 connector
The PS/2 connector is a 6-pin Mini-DIN connector used for connecting some keyboards and mice to a PC compatible computer system. Its name comes from the IBM Personal System/2 series of personal computers, with which it was introduced in 1987...
keyboard
Computer keyboard
In computing, a keyboard is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches...
, PS/2 mouse
Mouse (computing)
In computing, a mouse is a pointing device that functions by detecting two-dimensional motion relative to its supporting surface. Physically, a mouse consists of an object held under one of the user's hands, with one or more buttons...
, floppy disk controller
Floppy disk controller
A floppy disk controller is a special-purpose chip and associated disk controller circuitry that directs and controls reading from and writing to a computer's floppy disk drive . This article contains concepts common to FDCs based on the NEC µPD765 and Intel 8072A or 82072A and their descendants,...
and—more recently—the Trusted Platform Module
Trusted Platform Module
In computing, Trusted Platform Module is both the name of a published specification detailing a secure cryptoprocessor that can store cryptographic keys that protect information, as well as the general name of implementations of that specification, often called the "TPM chip" or "TPM Security...
(TPM). The physical wires of the LPC bus usually connect to the southbridge
Southbridge (computing)
The southbridge is one of the two chips in the core logic chipset on a personal computer motherboard, the other being the northbridge. The southbridge typically implements the slower capabilities of the motherboard in a northbridge/southbridge chipset computer architecture. In Intel chipset...
chip on a PC motherboard
Motherboard
In personal computers, a motherboard is the central printed circuit board in many modern computers and holds many of the crucial components of the system, providing connectors for other peripherals. The motherboard is sometimes alternatively known as the mainboard, system board, or, on Apple...
, which contains the circuit equivalents of the "legacy" onboard peripherals of the IBM PC/AT architecture, such as the keyboard controller
Intel MCS-48
The MCS-48 microcontroller series, Intel's first microcontroller, was originally released in 1976. Its first members were 8048, 8035 and 8748....
, the two programmable interrupt controllers
Intel 8259
The Intel 8259 is a Programmable Interrupt Controller designed for the Intel 8085 and Intel 8086 microprocessors. The initial part was 8259, a later A suffix version was upward compatible and usable with the 8086 or 8088 processor...
, the programmable interval timer
Intel 8253
The Intel 8253 and 8254 are Programmable Interval Timers , which perform timing and counting functions. They were primarily designed for the Intel 8080/8085-processors, but later used in x86-systems...
, and the two ISA DMA controllers
Intel 8237
Intel 8237 is a direct memory access controller , a part of the MCS 85 microprocessor family. It was used as the DMA controller in the original IBM PC and IBM XT...
.
The LPC bus was introduced by Intel in 1998 as a substitute for the Industry Standard Architecture
Industry Standard Architecture
Industry Standard Architecture is a computer bus standard for IBM PC compatible computers introduced with the IBM Personal Computer to support its Intel 8088 microprocessor's 8-bit external data bus and extended to 16 bits for the IBM Personal Computer/AT's Intel 80286 processor...
(ISA) bus.
Discussions
