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Đây là quyển sách tiếng anh về lĩnh vực công nghệ thông tin cho sinh viên và những ai có đam mê. Quyển sách này trình về lý thuyết ,phương pháp lập trình cho ngôn ngữ C và C++.
[...]... performance purposes The C5 1 can mix C code and assembly code by #PRAGMA directives (will be discussed in chapter 4) so that the C can embed inline assembly code or assembly routines when it is necessary The SRC option of C5 1 compiler can produce the assembly source code from C source code The C5 1 compiler compiles the C source code into object code, while the A51 assembler assembles the assembly source code... 8051 clock cycle is (1/12)10−6 second (1/12 µs) because the clock frequency is 12MHz A simple 8051 instruction takes 12 cycles (1 µs) to complete Of course, some multi-cycle instructions take more clock cycles A timer is a real-time clock for real-time programming Every timer comes with a counter which can be configured by programs to count the incoming pulses When the counter overflows (resets to zero)... Port B Port C PA 0-7 Split I/O PB 0-7 /A 8-1 5 PC 0-7 /A 0-7 External Devices Ex-Memory ADC Port D Port E PD/Serial PE 0-7 /ANALOG 0-7 External Devices Fig 1.2 Block Diagram of 68HC11 Microcontroller The Microchip’s PIC16 × 84 (68 bytes on-chip RAM, 14 bit instruction) microcontrollers are Programmable Intelligent Computer (PIC) family members, which are also commonly used for embedded systems The PICs are popular... flag 1.5.5 Clock Oscillator, Timer and Watchdog You know that time is a very important factor to consider in embedded system design All microcontrollers need an oscillator clock unit which generates the clock tick at a predetermined rate The clock is used to control the clocking requirement of the CPU for executing instructions and the configuration of timers For example, a classic 8051 clock cycle is (1/12)10−6... 1.5.1 Overall Architecture Every embedded system consists of customer-built hardware components supported by a Central Processing Unit (CPU), which is the heart of a microprocessor (µP) or microcontroller ( C) A microprocessor is a stand-alone CPU chip, and memory and I/O ports can be custom designed and expanded There is no on-chip memory or ports on the microprocessor A microprocessor chip is a single... 32, 64 bits), and CPU clock frequency for timing tick control, i.e the number of ticks (clock cycles) per second in measures of MHz Each instruction takes a few time ticks to complete MIPS (Million Instructions per Second), i.e the number of machine instructions completed per second, is another index to tell the CPU speed One machine cycle of the 8051 has 12 ticks If the clock is 12 MHz, then its MIPS... are connected to the data bus The Address Register stores the memory location of the data to be accessed (get or set) The Address Register is connected to the address bus In an embedded system, the CPU may never stop and run forever The CPU works in a cycle of fetching an instruction, decoding it, and executing it, known as the fetch-decode-execute cycle The cycle begins when an instruction is fetched... Liquid Crystal Displays (LCD), printers, alarms, actuators, etc Some devices support both input and output, such as communication interfaces including Network Interface Cards (NIC), modems, and mobile phones 1.5.4.1 Parallel Port A microcontroller is integrated with several parallel I/O ports, which are used to interface the microcontroller to outside devices such as switches, LCDs, keypads, and actuators... integrated circuit intended to operate for general purpose and can be embedded into embedded electronics hardware A microcontroller is an integrated chip which comes with built-in memory, I/O ports, timers, and other components Most embedded systems are built on microcontrollers, which run faster than a custom-built system with a microprocessor, because all components are integrated within a single chip... particular designated functions Embedded systems have been used for K Qian et al., Embedded Software Development with C, DOI 10.1007/97 8-1 -4 41 9-0 60 6-9 1, c Springer Science+Business Media, LLC 2009 1 2 1 Introduction to Embedded Systems almost a half century since the microprocessor was developed The first Intel microprocessor chip was designed for calculators and other simple systems in 1960’s Since . 30071 USA ddharing@atronixengineering.com ISBN 97 8-1 -4 41 9-0 60 5-2 e -ISBN 97 8-1 -4 41 9-0 60 6-9 DOI 10.1007/97 8-1 -4 41 9-0 60 6-9 Springer Dordrecht Heidelberg London New York Library of Congress Control. forever. The CPU works in a cycle of fetching an instruction, decoding it, and executing it, known as the fetch-decode-execute cycle. The cycle begins when