Chapter 1 The 8051 Microcontroller

Section 1.1 Microcontrollers and Embedded Processors

General-purpose microprocessor 2017/4/13 General-purpose microprocessor CPU for Computers No RAM, ROM, I/O on CPU chip itself Example：Intel’s x86, Motorola’s 680x0 Many chips on mother’s board Intel’s x86: 8086,8088,80386,80486, Pentium Motorola’s 680x0: 68000, 68010, 68020,68030,6040 Data Bus CPU General-Purpose Micro-processor Serial COM Port I/O Port RAM ROM Timer Address Bus Figure 1-1 (a) General-Purpose Microprocessor System

Microcontroller A smaller computer On-chip RAM, ROM, I/O ports... Example：Motorola’s 6811, Intel’s 8051, Zilog’s Z8 and PIC 16X CPU RAM ROM A single chip Serial COM Port I/O Port Timer Figure 1-1 (b) Microcontroller

Microprocessor v.s. Microcontroller 2017/4/13 Microprocessor v.s. Microcontroller Microprocessor CPU is stand-alone, RAM, ROM, I/O, timer are separate designer can decide on the amount of ROM, RAM and I/O ports. expansive versatility general-purpose Microcontroller CPU, RAM, ROM, I/O and timer are all on a single chip fix amount of on-chip ROM, RAM, I/O ports for applications in which cost, power and space are critical single-purpose versatility 多用途的: any number of applications for PC

Embedded System（嵌入式系統） 2017/4/13 Embedded System（嵌入式系統） Embedded system means the processor is embedded into that application. An embedded product uses a microprocessor or microcontroller to do one task only. In an embedded system, there is only one application software that is typically burned into ROM. Example：printer, keyboard, video game player Example：Table 1-1, some embedded products using microconrollers processor 整合到整個系統中, 你只看到此系統的外觀, 應用, 感覺不到有 processor 在其中. Embedded system 通常只有一項應用, 而 PC 有許多 applications (game, accounting, fax, mail...) A printer is an example of embedded system since the processor inside it performs one task only.

Processors in Embedded Systems 2017/4/13 Processors in Embedded Systems Which is your choice for an embedded product？ microcontroller cost down embedded processor ＝ microcontroller microprocessor In future, an entire computer on a chip high-end embedded systems use microprocessors 殺雞用牛刀！ advantage：soon software development, all (appliances) in one.

Three criteria in Choosing a Microcontroller meeting the computing needs of the task efficiently and cost effectively speed, the amount of ROM and RAM, the number of I/O ports and timers, size, packaging, power consumption easy to upgrade cost per unit availability of software development tools assemblers, debuggers, C compilers, emulator, simulator, technical support wide availability and reliable sources of the microcontrollers.

Section 1.2 Overview of the 8051 Family

2017/4/13 History of 8051 1981, Intel MCS-51 The 8051 became popular after Intel allowed other manufacturers to make and market an flavor of the 8051. different speed, amount of o-chip ROM code-compatible with the original 8051 form a 8051 family 在 Intel 允許廠商設計相容的 8051 IC 後, 8051 才真正的 popular.

Table 1-3：Features of the 8051 Feature Quantity Notes ROM 4K bytes a fixed program RAM 128 bytes temporary data Timers 2 Timer/counter 0,1 I/O pins 32 P0,P1,P2,P3 Serial port 1 TxD, RxD Interrupt sources 6

8051 Pin Diagram 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 P1.0 P1.1 P1.2 P1.3 P1.4 P1.5 P1.6 P1.7 RST (RXD)P3.0 (TXD)P3.1 (T0)P3.4 (T1)P3.5 XTAL2 XTAL1 GND (INT0)P3.2 (INT1)P3.3 (RD)P3.7 (WR)P3.6 Vcc P0.0(AD0) P0.1(AD1) P0.2(AD2) P0.3(AD3) P0.4(AD4) P0.5(AD5) P0.6(AD6) P0.7(AD7) EA/VPP ALE/PROG PSEN P2.7(A15) P2.6(A14) P2.5(A13) P2.4(A12) P2.3(A11) P2.2(A10) P2.1(A9) P2.0(A8) 8051 (8031)

Inside Architecture of 8051 2017/4/13 Inside Architecture of 8051 External interrupts On-chip ROM for program code Timer/Counter Interrupt Control On-chip RAM Timer 1 Counter Inputs Timer 0 CPU Serial Port Bus Control 4 I/O Ports OSC P0 P1 P2 P3 TxD RxD Address/Data Figure 1-2. Inside the 8051 Microcontroller Block Diagram

Other 8051 family Table 1-4：Comparison of the 8051 Family Members Feature 8051 8052 8031 ROM (program space in bytes) 4K 8K 0K RAM (bytes) 128 256 128 Timers 2 3 2 I/O pins 32 32 32 Serial port 1 1 1 Interrupt sources 6 8 6

Various 8051 Microcontrollers 2017/4/13 Various 8051 Microcontrollers 8751 microcontroller AT89C51 from Atmel Corporation DS5000 from Dallas Semiconductor OTP (one-time-programmable) version of the 8051 8051 family from Philips Note： Memory is the most difference between them. Please reference to Chapter 14 and Chapter 15. You ignore this part until your really design. 8751 microcontroller (UV-EPROM) AT89C51 from Atmel Corporation (flash memory) Table 1-5, Table 1-6 DS5000 from Dallas Semiconductor (NV-RAM) Table 1-7, Table 1-8 OTP version of the 8051 8051 family from Philips (add A-to-D converters, D-to-A converters)

You are able to Compare and contrast microprocessors and microcontrollers Describe the advantages of microcontrollers for some applications Explain the concept of embedded systems Discuss criteria to consider in choosing a microcontroller Explain the variations of speed, packaging, memory, and cost per unit and how these affect choosing a microcontroller Compare and contrast the various members of the 8051 family Compare 8051 microcontrollers offered by various manufacturers

Homework Chapter 0 Problems：25,26,27,28,29