MSC-51

Transcription

1 اصول ميکروکامپيوترها استاد درس: دکتر ا درس و Website برای تکاليف و... : ١ پانزدهم فصل ا شنايی با ميکروکنترولرها خانواده MSC-51 ٢ ١

2 Contents: Introduction Block Diagram and Pin Description of the 8051 Registers Memory Mapping in 8051 Stack in the 8051 Addressing Modes and Instructions I/O Port Programming Timer ٣ Interrupt Why do we need to learn Microprocessors/controllers? The microprocessor is the core of computer systems. Nowadays many communication, digital entertainment, portable devices, are controlled by them. A designer should know what types of components he/she needs, ways to reduce production costs and product reliable. ٤ ٢

3 Different aspects of a microprocessor/controller Hardware :Interface to the real world Software :order how to deal with inputs ٥ ٦ The necessary tools for a microprocessor/controller CPU: Central Processing Unit I/O: Input /Output Bus: Address bus & Data bus Memory: RAM & ROM Timer Interrupt Serial Port Parallel Port ٣

4 Microprocessor vs. 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 ٧ مقايسه ميکروکامپيوتر با ميکروکنترولر ميکروکنترولرها در کاربرد های (خاص) ثابتی مورد استفاده قرار می گيرند. به دليل نوع کاربرد دارای ملزومات سخت افزاری و نرم افزاری متفاوت هستند. به دليل کاربردهای کنترلی به مجموعه دستورالعمل متفاوتی نياز دارد. درميکروکنترولرها برنامه کنترلی در ROM قرار می گيرد. نياز به RAM کم است. سيستم های ميکرو کامپيوتری دارای کاربرد عام هستند. به دليل نياز به سخت افزار بيشتر سيستم های م يکروکامپيوتری گرانتر است. ٨ ٤

5 Embedded System 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 ٩ More examples of embedded systems Mobile phone Braking systems Traction control Engine management units Steer-by-wire (includes fly-by-wire) Cruise control Video Cassette Recorder (VCR) Auto-pilots Flight control systems Radar systems Missile guidance systems ١٠ ٥

6 Three criteria in Choosing a Microcontroller 1. 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 2. Availability of software development tools Assemblers, Debuggers, C-compilers, Emulator, Simulator, Technical support 3. Wide availability and reliable sources of the microcontrollers. ١١ مقايسه ميکروکامپيوتر با ميکروکنترولر مينيمم سيستم يک ميکروکامپيوتر ١٢ ٦

7 Microprocessors: CPU for Microcomputers No RAM, ROM, I/O on CPU chip itself Example:Z80-CPU, Intel s 8085A, Intel s x86, Motorola s 680x0 CPU Data Bus Many chips on mother s board General- Purpose Microprocessor RAM ROM I/O Port Timer Serial COM Port Address Bus ١٣ General-Purpose Microcomputer System Microcontroller : A smaller computer On-chip RAM, ROM, I/O ports... Example: Intel s 8051, Motorola s 6811, Zilog s Z8 and PIC 16X CPU I/O Port RAM Timer ROM Serial COM Port Microcontroller A single chip ١٤ ٧

8 Microcontroller Block Diagram External interrupts Interrupt Control On-chip ROM for program code On-chip RAM Timer/Counter Timer 1 Timer 0 Counter Inputs CPU OSC Bus Control 4 I/O Ports Serial Port P0 P1 P2 P3 TxD RxD Address/Data ١٥ 8051 Block Diagram INT1 INT0 شماي داخلی میکروکنترولر 8051 Interrupt control Timer2 (8032 / 8052) Timer 1 Timer 0 Serial port Other registers 128 bytes RAM (8032 / 8052) 128 bytes RAM ROM 0K /8032 4K K Timer 2 (8032/8052) Timer 1 Timer 0 T2EX* T2* T1* T0* CPU باس داخلی Oscillator Bus control I / O ports Serial Port ١٦ EA RST ALE PSEN P0 P2 P1 P3 TXD* RXD* Address/Data ٨

9 ويژگی های 8051: ( ۴ کيلوبايت ۸) ROM کيلوبايت برای 8052 ( ۱۲۸ بايت ۲۵۶) RAM بايت برای 8052 ۴ پورت ورودی- خروجی ۸ بيتی( PIO ) - دو تايمر ۱۶ بيتی (۳ تايمر برای 8052) پورت سريال( Interface (Serial امکان دسترسی به ۶۴ کيلوبايت حافظه بيرونی برای برنامه( Code ) امکان دسترسی به ۶۴ کيلوبايت حافظه بيرونی برای داده (Data) امکان کار روی بيت Processor) (Boolean ۲۱۰ بيت قابل ا درس دهی توانايی انجام عمليات ضرب و تقسيم در کمتر از ۴μs ١٧ ويژگی های خانواده 8051 ١٨ ٩

10 فرکانس های کار 8051 ١٩ تصوير ا ی سی 8052 ساخت کارخانه Atmel ٢٠ ١٠

11 ROM memory map in 8051 family 0000H 4k 0000H 0000H 0FFFH 8751 AT89C51 8k 8752 AT89C52 32k DS FFFH 7FFFH ٢١ from Atmel Corporation from Dallas Semiconductor Pin Description of the 8051 ٢٢ P1.0 P1.1 P1.2 P1.3 P1.4 P1.5 P1.6 P1.7 RST (RXD)P3.0 (TXD)P3.1 (INT0)P3.2 (INT1)P3.3 (T0)P3.4 (T1)P3.5 (WR)P3.6 (RD)P3.7 XTAL2 XTAL1 GND (8031) 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) ١١

12 رجيسترهای داخلی ميکروکنترولر 8051 PSW PC SP DPH DPL Data Pointer (DPTR) ACC B بيت های مربوط به رجيستر پرچم R7 R6 R5 R4 R3 R2 R1 R0 ٢٣ Program Status Word (PSW) Registers PSW A B R0 R1 R2 R3 R4 R5 R6 R7 DPTR PC DPH PC DPL Some bit Register Some 8-bitt Registers of the 8051 ٢٤ ١٢

13 ۸۰ بايت رجيسترها وRAM داخلی ميکروکنترولر 8051 ۱۲۸ بيت قابل ا درس دهی SETB 7FH MOV A, 7FH معادل (7FH) LD A, ادرس های RAM داخلی يک بايتی است ٢٥ رجيسترهای داخلی ميکروکنترولر 8051 ٢٦ Accumulator Program Status Word B Register Stack Pointer Data Pointer Port Register Power Control Register PCON Low Timer Register High Timer Register Timer Mode Register TMOD Timer Control Register TCON Interrupt Enable Register IE Interrupt Priority Register IP Serial Port Data Register SBUF Serial Port Control Register SCON ACC or A PSW B SP DPTR Pi i= 0, 1, 2, 3 TLi i=0, 1 THi i=0, 1 ١٣

14 علامت اختصاری نام وا درس های رجيستر های (با کارکرد) خاص ٢٧ ادامه جدول ٢٨ ١٤

15 فضای RAM داخلی ميکروکنترولر 8051 و 8052 Internal RAM SFR s MOV A, 0F0H معادل (0F0H) LD A, Direct Add. mode ا درس رجيسترB است F0H ٢٩ MOV R0, #0F0H MOV LD R0, 0F0H LD A, (R0) Indirect Add. Mode RAM memory space allocation in the FH Scratch pad RAM 30H ٣٠ 2FH 20H 1FH 18H 17H 10H 0FH 08H 07H 00H Bit-Addressable RAM Register Bank 3 Register Bank 2 (Stack) Register Bank 1 Register Bank 0 ١٥

16 Stack in the 8051 The register used to access the stack is called SP (stack pointer) register. 7FH 30H Scratch pad RAM MOV The stack pointer in the 8051 is only 8 bits wide, which means that it can take value 00 to FFH. When 8051 powered up, the SP register contains value 07. ٣١ SP, #30H ; Initialize Stack Pointer 2FH 20H 1FH 18H 17H 10H 0FH 08H 07H 00H Bit-Addressable RAM Register Bank 3 Register Bank 2 (Stack) Register Bank 1 Register Bank 0 پايه های (Pinots) 8051 (مدل سخت افزاری) Program Store Enable (PSEN) External Access (EA) 0V ExternalROM EA = 5V InternalROM Upon reset, all ports are configured as out-put ports. ٣٢ ١٦

17 Pins of 8051 (1/4) Vcc(pin 40): Vcc provides supply voltage to the chip. The voltage source is +5V. GND(pin 20):Ground XTAL1 and XTAL2(pins 19,18) ٣٣ Figure (a). XTAL Connection to 8051 Using a quartz crystal oscillator We can observe the frequency on the XTAL2 pin 18. C2 30pF C1 30pF XTAL2 XTAL1 ٣٤ GND ١٧

18 RST(pin 9):Reset Pins of 8051 (2/4) It is an input pin and is active high (normally low). The high pulse must be high at least 2 machine cycles. It is a power-on reset. Upon applying a high pulse to RST, the microcontroller will reset and all values in registers will be lost. ٣٥ Reset values of some 8051 registers + Vcc Figure (b). Power-On RESET Circuit 10 uf 8.2 K 30 pf 30 pf MHz EA/VPP X1 X2 RST ٣٦ ١٨

19 Pins of 8051 (3/4) EA (pin 31):External Access There is no on-chip ROM in 8031 and The EA pin is connected to GND to indicate the code is stored externally. PSEN & ALE are used for external ROM. For 8051, EA pin is connected to Vcc. PSEN (pin 29):Program Store ENable This is an output pin and is connected to the OE pin of the ROM. ٣٧ ٣٨ Pins of 8051 (4/4) ALE (pin 30):address latch enable It is an output pin and is active high port 0 provides both address and data. The ALE pin is used for de-multiplexing the address and data by connecting to the G pin of the 74LS373 latch. I/O port pins The four ports P0, P1, P2, and P3. Each port uses 8 pins. All I/O pins are bi-directional. ١٩

20 Pins of I/O Port The 8051 has four I/O ports Port 0 (pins 32-39):P0 (P0.0~P0.7) Port 1 (pins 1-8) :P1(P1.0~P1.7) Port 2(pins 21-28):P2(P2.0~P2.7) Port 3(pins 10-17):P3(P3.0~P3.7) Each port has 8 pins. Named P0.X (X=0,1,...,7), P1.X, P2.X, P3.X Ex:P0.0 is the bit 0(LSB)of P0 Ex:P0.7 is the bit 7(MSB)of P0 These 8 bits form a byte. ٣٩ Each port can be used as input or output (bi-direction). Port 3 Alternate Functions P3 Bit Function Pin P3.0 P3.1 P3.2 P3.3 P3.4 P3.5 P3.6 P3.7 RxD TxD INT0 INT1 T0 T1 WR RD ٤٠ ٢٠

21 ٤١ نحوه Demultiplex کردن خطوط Data و Address ٤٢ ٢١

22 نحوه استفاده از حافظه خارجی ٤٣ Interfacing To External Memory 74HC138 A 13 A 14 A 15 A B C E1 E2 E3 O 0 O 1 O 2 O 3 O 4 O 5 O 6 O P2.7 P2.6 P2.5 P2.4 P2.3 P2.2 P2.1 P2.0 ALE P0.7 P0.6 P0.5 P0.4 P0.3 P0.2 P0.1 P0.0 G D D D D D D D D 373 Q Q Q Q D Q Q Q A 12 A 11 A 10 A 9 A 8 A 7 A 6 A 5 A 4 A 3 A 2 A 1 A 0 OE CS 8 K EPROM D 0 D 1 D 2 D 3 D 4 D 5 D 6 D 7 D 0 D 1 D 2 D 3 D 4 D 5 D 6 D 7 WR RD CS 8 K RAM A 12 A 11 A 10 A 9 A 8 A 7 A 6 A 5 A 4 A 3 A 2 A 1 A 0 PSEN (P3.6) (P3.7) WR RD ٤٤ EA ٢٢

23 ٤٥ نحوه استفاده از دو بانک حافظه RAM وROM خارجی با يک مدارDecoder Add. ٤٦ Hardware Structure of I/O Pin Each pin of I/O ports Internal CPU bus:communicate with CPU A D-latch stores the value of this pin D-latch is controlled by Write to latch Write to latch=1:write data into the D latch 2 Tri-state buffer TB1: controlled by Read pin Read pin=1:really reads the data present at the pin TB2: controlled by Read latch Read latch=1:to read value from internal latch A transistor M1 gate Gate=0: open Gate=1: close ٢٣

24 A Pin of Port 1 Read latch TB2 Vcc Load(R1) Internal CPU bus D Q P1.X P1.X pin Write to latch Clk Q M1 Read pin TB1 P0.x ٤٧ 8051 IC Writing 1 to Output Pin P1.X Read latch 1. write a 1 to the pin SETB P1.X Internal CPU bus Write to latch Vcc TB2 Load(L1) 2. output pin is Vcc D Q 1 P1.X P1.X pin Clk Q 0 M1 output 1 Read pin TB1 ٤٨ 8051 IC ٢٤

25 Writing 0 to Output Pin P1.X Read latch 1. write a 0 to the pin MOV P1,#00H Internal CPU bus Write to latch Vcc TB2 Load(L1) 2. output pin is ground 0 D Q P1.X P1.X pin Clk Q 1 output 0 M1 Read pin TB1 ٤٩ 8051 IC Reading High at Input Pin Read latch 1. write a 1 to the pin MOV P1, #0FFH TB2 Vcc Load(L1) 2. MOV A, P1 external pin=high Internal CPU bus Write to latch D Q P1.X Clk Q 1 0 M1 1 P1.X pin TB1 ٥٠ Read pin 3. Read pin=1 Read latch=0 Write to latch= IC ٢٥

26 Reading Low at Input Pin Read latch 1. write a 1 to the pin MOV P1,#0FFH Internal CPU bus TB2 1 D Q P1.X Vcc Load(L1) 0 2. MOV A,P1 external pin=low P1.X pin Write to latch Clk Q 0 M1 TB1 ٥١ Read pin 3. Read pin=1 Read latch=0 Write to latch= IC پورت ها هرکدام به صورت بايت يا بيت قابل ا درس دهی هستند ( Single-Bit Addressability of Ports) Port's Bit D0 D1 D2 D3 D4 D5 D6 P3 P3.0 P3.1 P3.2 P3.3 P3.4 P3.5 P3.6 P2 P2.0 P2.1 P2.2 P2.3 P2.4 P2.5 P2.6 Pl P1.0 Pl.1 P1.2 P1.3 P1.4 P1.5 P1.6 P0 P0.0 P0.1 P0.2 P0.3 P0.4 P0.5 P0.6 ٥٢ SETB P1.2 ; P1.2=1 CLR P1.2 ; P1.2=0 CPL P30 ; Complement P1.2 MOV P1, 0FFH ; P1 = FF (P1 is configured I/P ) ٢٦

27 Other Pins P1, P2, and P3 have internal pull-up resisters. P1, P2, and P3 are not open drain. P0 has no internal pull-up resistors and does not connects to Vcc inside the P0 is open drain. However, for a programmer, it is the same to program P0, P1, P2 and P3. All the ports upon RESET are configured as output. P0.x ٥٣ A Pin of Port 0 Read latch TB2 Internal CPU bus D Q P1.X P0.X pin Write to latch Clk Q M1 Read pin TB1 ٥٤ 8051 IC P1.x ٢٧

28 Port 0 with Pull-Up Resistors Vcc 10 K DS P0.0 P0.1 P0.2 P0.3 P0.4 P0.5 P0.6 P0.7 Port 0 ٥٥ RESET Value of Some 8051 Registers Register Reset Value PC 0000 ACC 0000 B 0000 PSW 0000 SP 0007 DPTR 0000 ٥٦ RAM are all zero. ٢٨

29 رجيسترهای مخصوص تايمرهای داخلی 8051/2 ٥٧ Timer : ٥٨ ٢٩

30 رجيستر کنترل کننده تايمرها( Register (TCON TF1 TR1 TF0 TR0 IE1 IT1 IE0 IT0 TF1: Timer 1 overflow flag. TR1: Timer 1 run control bit.(tr1=1 Timer1 runs) TF0: Timer 0 overflow flag. TR0: Timer 0 run control bit..(tr0=1 Timer0 runs) IE1: External interrupt 1 edge flag. (IE-Flags are used by CPU) IT1: External interrupt 1 type flag.(it1=1 Edge-triggered) IE0: External interrupt 0 edge flag. IT0: External interrupt 0 type flag. ٥٩ رجيستر تعيين کننده مود تايمرها Register) (TMOD Gate C/T M1 M0 Gate C/T M1 M0 Timer1 Timer0 Gate : When set, timer only runs while INT0 (or 1) is high. C/T : Counter/Timer select bit. M1 : Mode bit 1. M0 : Mode bit 0. M1 0 M0 0 Mode 13 bit Timer Mode bit Timer Mode bit auto-reload Mode ٦٠ 1 1 Split Mode ٣٠

31 Mode های مختلف تايمرها XTAL Oscillator f/12 C/ T= 0 TR=1 TLX THX (8bits) (8bits) TF is set when FFFF 0000 TFX Overflow Flag Mode1 XTAL Oscillator f/12 C/ T= 0 TR=1 TLX THX (5bits) (8bits) TF is set when FFFF 0000 TFX Overflow Flag Mode0 Mode2 ٦١ XTAL Oscillator f/12 C/ T= 0 TR=1 TLX (8bits) THX (8bits) Reload TFX Overflow Flag Mode 3 Timer1: Timer Clock TL1 (8bits) TH1 (8bits) Timer0: Timer Clock TL0 (8bits) TF0 Overflow Flag ٦٢ 12 f Osci TL0 (8bits) TF1 Overflow Flag ٣١

32 عملکرد تايمر ۱ در Mode1 ٦٣ Interrupt : ٦٤ ٣٢

33 Interrupt Enable (IE) Register EA - ET2 ES ET1 EX1 ET0 EX0 EA : Global enable/disable. --- : Undefined. ET2 :Enable Timer 2 interrupt. ES :Enable Serial port interrupt. ET1 :Enable Timer 1 interrupt. EX1 :Enable External 1 interrupt. ET0 : Enable Timer 0 interrupt. EX0 : Enable External 0 interrupt. ٦٥ حالت ها ا درس دهی 8051 The 8051Addressing Modes ٦٦ ٣٣

34 (ا درس دهی با ثبات) -1 Register Addressing Mode Operand به صورت يک بايت در يکی از رجيسترهای داخلی( Rn ) قرار دارد. MOV A, R7 ; Copy the contents of R7 into A ADD A, R7 ; Add the contents of R7 to A مثال: MOV MOV R7, A A, R5 INC R0 ; Increment R0 DEC R1 ; Decrement R1 ANL A, R6 ; Logic AND (A+R6) ٦٧ (ا درس دهی مستقيم) 2-Direct Addressing Mode MOV A, P1 MOV A, 7FH ا درس Operand به صورت يک بايت داده می شود ; Copy the contents of P1 (7FH) into A ; Copy the contents of memory location (7FH) into A مثال: INC 7FH ; Increment memory location (7FH) MOV MOV P1, A A, DPH ADD A, 4 ANL A, 37H ; AND Logically MOV 4, 7 ; Copy the contents of R7 into R4 MOV ٦٨ R4, R7 Invalid Instruction ٣٤

35 (ا درس دهی غير مستقيم) Mode -3 Indirect Addressing ا درس در يکی از رجيسترهای R0 يا R1 قرار دارد MOV ; Copy the contents of (R7) into A A B MOV MOVX ; Read from external memory A ; Write to external memory MOVX ; Read from external memory A ; Write to external memory ADD ; Add the contents of (R0) to A ANL ; AND Logic ***** مثال: ٦٩ (ا درس دهی بلافصل) 4-Immediate Addressing Mode ٧٠ Data ا درس يا Operand مقدار ثابتی است MOV A, #12H MOV DPTR, #2000H MOV DPL #00 MOV DPH #2O MOV R4, #62 MOV R4, #COUNT ADD A, #25H ANL A, #33 مثال: ٣٥

36 (ا درس دهی نسبی) Mode 5-Relative Addressing از اين ا درس دهی برای پرش های نسبی کوتاه (۱۲۷- تا ۱۲۸+) استفاده می شود JZ AGAIN ; Jump if A=0 JNZ AGAIN ; Jump if A 0 SJMP 5 ; Jump forward 5 locations SJMP 0F6H ; Jump back 10 locations JB P1.2, LABLE1 ; Jump if the bit is set (P1.2=1) JC LABLE2 ; Jump if Carry is set (Cy=1) JNC LABLE2 ; Jump if Carry is not set (Cy=0) SJMP START مثال: DJNZ Ri, 5 ; Decrement Ri and jump if Ri 0 ٧١ DJNZ CJNE R7, AGIN R5, #73H, AGAIN ;Compare and Jump if Not Equal مثال: (ا درس دهی مطلق) 6- Absolute Addressing Mode فقط در دستورات ACALL و AJMP استفاده می شود. ا درس دارای ۱۱ بيت است. به هر خانه ای در صفحه ۲ کيلوبايت حاضر می تواند پرش کند. AJMP ACALL THERE ;Absolute Jump THERE ;Absolute Jump ٧٢ ٣٦

37 (ا درس دهی طولانی) 7- Long Addressing Mode فقط در دستورات LCALL و LJMP استفاده می شود. ا درس دارای ۱۶ بيت است. به هر خانه ای در حافظه می تواند پرش کند. LJMP LCALL THERE ;Long Jump THERE ;Long Call مثال: ٧٣ (ا درس دهی انديس دار) -8 Indexed Addressing Mode فقط در دستورات JMP و MOVC استفاده می شود. ا درس حاصل مساوی است با محتويات PC يا DPTR (به عنوان ا درس پايه) بعلاوه محتويات ا کومولاتور (به عنوان ا فست). اين مود ا درس دهی کار با جداول را ا سان می کند. MOVC MOVC ;Read from address (A+PC) ;Read from address (A+DPTR) مثال: Jump to address (A+DPTR) ٧٤ ٣٧

38 ا شنايی بادستورالعمل ها و برنامه نويسی ميکروکنترولر 8051 ٧٥ SETBbit ; bit=1 CLR bit ; bit=0 دستورالعمل های مربوط به bit SETB C ; CY=1 SETB P0.0 ;bit 0 from port 0 =1 SETB P3.7 ;bit 7 from port 3 =1 SETB ACC.2 ;bit 2 from ACCUMULATOR =1 SETB 05 ;set high D5 of RAM loc. 20h Note: CLR instruction is as same as SETB i.e.: CLR C ; CY=0 But following instruction is only for CLR: ٧٦ CLR A ; A=0 ٣٨

39 DEC byte ;byte=byte-1 INC byte ;byte=byte+1 INC R7 DEC A DEC 40H ; [40]=[40]-1 SETB P0.0.. ACALL UP.. UP: CLR P0.0. RET ٧٧ Call instruction ACALL SUBROUTINE1 LCALL SUBROUTINE2 دستورالعمل های پرش شرطی JZ JNZ DJNZ CJNE A, byte CJNE Reg, data JC JNC JB JNB Jump if A=0 Jump if A 0 Decrement and jump if A 0 Jump if A byte Jump if byte data Jump if CY=1 Jump if CY=0 Jump if bit=1 Jump if bit=0 ٧٨ JBC Jump if bit=1 and clear bit ٣٩

40 Example 1: Write a program to a) clear ACC, b) add 3 to the accumulator ten times. Solution: ;This program adds value 3 to the ACC ten times MOV A, #0 ;A=0, clear ACC MOV R2, #10 ;load counter R2=10 AGAIN: ADD A, #03 ;add 03 to ACC DJNZ R2, AGAIN ;repeat until R2 = 0 (10 times) MOV R5, A ;save A in R5 ٧٩ Example 2 : Port 1 as input To make port 1 an input port, it must be programmed as such, by writing 1 to all its bits. Port 1 is configured first as an input port by writing 1 s to it, then data is received from that port and saved in R7, R6, and R5. Solution: ٨٠ MOV A,#0FFH ;A=FF hex MOV P1, A ;make P1 an input port by writing all 1s to it MOV A,Pl ;get data from P1 MOV R7, A ;save it in reg R7 ACALL DEALY ;wait MOV A, P1 ;get another data from PI MOV R6, A ;save it in reg R6 ACALL DELAY :wait MOV A,P1 ;get another data from P1 MOV R5, A ;save it in reg R5 ٤٠

41 Example 3: Write a program to toggle all the bits of P2 continuously. Solution: ٨١ MOV A, #55H BACK: MOV P2, A ACALL DELAY CPL Example 4: SJMP A BACK First Configure Port 2 as an input port. Then receive data from that port and is sent to P1 continuously. Solution: MOV A, #0FFH ;A=FF hex MOV P2, A ;make P2 an input port by writing all 1s to it BACK: MOV A, P2 ;get data from P2 MOV P1, A ;send it to Port 1 SJMP BACK ;keep doing that Example 5: Assume that RAM locations have the following values. Write a program to find the sum of the values. At the end of the program, register A should contain the low byte and R7 the high byte. All values are in hex. 40=(7D), 41=(EB), 42=(C5), 43=(5B), 44=(30) Solution: MOV R0, #40H ;load pointer MOV R2, #5 ;load counter CLR A ;A=0 MOV R7, A ;clear R7 AGAIN: ADD ;add the byte pointed to by R0 JNC NEXT ;if CY=0 don't accumulate carry INC R7 ;keep track of carries NEXT: INC R0 ;increment pointer if carry is set DJNZ R2, AGAIN ;repeat until R2 is zero ٨٢ ٤١

42 Example 6: Assume internal RAM memory locations 40H - 44H contain the daily temperature for five days, as shown below. Search to see if any of the values equals 65. lf value 65 does exist in the table, give its location to R4; otherwise, make R4 = 0. 40H=(76), 41H=(79), 42H=(69), 43H=(65), 44H=(62) Solution: ٨٣ MOV R4,#0 ; R4=O MOV R0, #40H ; load pointer MOV R2, #05 ; load counter MOV A, #65 ; A=65, value searched for BACK: CJNE NEXT ;compare RAM data with 65 MOV R4, RO ; if 65, save address SJMP EXIT ;and exit NEXT: INC R0 ; otherwise increment pointer EXIT... DJNZ R2, BACK ; keep checking until count=0 مثال ۷: برنامه ای بنويسيد که ۱۶ خانه حافظه از ا درس ۶۰ به بعد را پاک کند. CLR A MOV R1, #60 MOV R7, #16 AGIN: A INC R1 DJNZ R7, AGIN MOV R1, #60 MOV R2, #35 MOV R7, #16 BACK: MOV A INC R1 INC R2 مثال ۸: برنامه ای بنويسيد که ١٦ خانه حافظه از ا درس ٦٠ به بعد را در خانه های حافظه از ٣٥ به بعد کپی کند. DJNZ R7, BACK ٨٤ ٤٢

43 مثال ۹: برنامه ای بنويسيد که در پايه P1.2 ايجاد شکل موج مربعی کند. ٨٥ Example 10: In the following program, we are creating a square wave of 50% duty cycle on the P 1.5 bit. Timer 0 is used to generate the time delay. MOV TMOD, #01 ;Timer 0, mode 1 (16-bit mode) HERE: MOV TL0, #0F2H ;TL0= F2H, the low byte MOV THO,#OFFH ;THO=FFH, the high byte CPL P1.5 ;toggle PI.5 ACALL DELAY SJMP HERE ;load TH,TL again ; -delay using timer 0 DELAY: SETB TR0 ;start the timer 0 AGAIN: JNB TF0, AGAIN ;monitor timer flag 0 until it rolls over CLR TR0 ;stop timer 0 CLR TF0 ;clear timer 0 flag RET ٨٦ ٤٣

44 Example 11: Examine the following program and find the time delay in seconds. Exclude the over-head due to the instructions in the loop. MOV TMOD, #10H ; Timer 1, mode 1(16-bit) MOV R3, #200 ; counter for multiple delay AGAIN: MOV TL1, #08 ; TL1=08, low byte of timer MOV TH1, #01 ; TH1=01, Hi byte SETB TR1 ; start the timer 1 BACK: JNB TF1, BACK ; stay until timer rolls over Solution: CLR TRI ; stop timer 1 CLR TF1 ; clear timer flag 1 DJNZ R3, AGAIN ; if R3 not zero then reload timer TH - TL = 0108H = 264 in decimal and = Now x μs = ms, and for 200 of them we have 200 x ms = seconds. ٨٧ Example 12: Assuming that XT AL = MHz, find (a) the frequency of the square wave generated on pin P1.0 in the following program, and (b) the smallest frequency achievable in this program, and the TH value to do that. MOV TMOD, #20H ; T1/ mode 2/ 8-bit/ auto reload MOV TH1, #5 ; TH1=5 SETB TR1 ; start the timer 1 BACK: JNB TF1, BACK ; stay till timer rolls over CPL P1.0 ; comp. P1.0 to get hi, lo CLR TF1 ; clear tl.mer J.ag 1 SJMP BACK ; mode 2 is auto-reload Solution: (a) In mode 2 we do not need to reload TH since it is auto-reload. Now (256-05) x ).is = 251 x ).is = ).is is the high portion of the pulse. Since it is a 50% duty cycle square wave, the period T is twice that; as a result T = 2 x ).is = ).is and the frequency = khz. (b) To get the smallest frequency, we need the largest T and that is achieved when TH= 00. In ٨٨ that case, we have T = 2 x 256 x ).is = ).is and the frequency = 1.8 khz. ٤٤

45 نحوه اتصال ورودی و خروجی ساده به ميکروکنترولر ٨٩ 4 4 Matrix Hex Keypad 8051 Column 0 Column 1 Column 2 Column 3 P1.7 P1.6 P1.5 P1.4 P1.3 P1.2 P1.1 P1.0 Row 3 Row 2 C D E F 8 9 A B Row Row 0 ٩٠ ٤٥

46 ساخت شمارنده يک رقمی باAT89C51 ٩١ نحوه اتصال LCD به ميکروکنترولر 8051 RS: Register Select RS = D/C E: Enable 8051 E R/ W RS DB7 DB0 communications bus microcontroller ٩٢ 8 LCD controller ٤٦

47 LCD Command Codes code command to LCD Instruction Register 1 Clear display screen 2 Return home 4 Decrement cursor (shift cursor to left) 6 Increment cursor (shift cursor to right) 5 Shift display right 7 Shift display left 8 Display off, cursor off A Display off, cursor on C Display on, cursor off- E Display on, cursor not blinking F Display on, cursor blinking 10 Shift cursor position to left 14 Shift cursor position to right ٩٣ LCD Command Codes code command to LCD Instruction Register 18 Shift the entire display to the left 1C Shift the entire display to the right 80 Force cursor to beginning of 1st line C0 Force cursor to beginning of 2nd line 38 2 lines and 5x7 matrix (To initialize the LCD) ٩٤ 40 Characters / Line ٤٧

48 Example 13: نحوه Initialize کردن وارتباط با LCD ; Check busy flag before sending data, command to LCD. P1=data port ; P2.0 connected to RS (D/C) pin. P2.1 connected to R/W pin. ; P2.2 connected to E pin ORG MOV A, #38H ;Init. LCD 2 lines,5x7 matrix ACALL COMMAND ; issue command MOV A, #0EH ; LCD on, cursor on ACALL COMMAND ; issue command MOV A, #01H ; clear LCD command ACALL COMMAND ; issue command MOV A, #06H ; shift cursor right ACALL COMMAND ; issue command MOV A, #86H ; cursor: line 1, pos. 6 ACALL COMMAND ; command subroutine MOV A, #'N' ; display letter N ٩٥ ACALL DATA_DISPLAY Example 13 (Continued): MOV A,#'O ; display letter ACALL DATA DISPLAY HERE: SJMP HERE ; STAY HERE COMMAND: ACALL READY is LCD ready? MOV P1, A ; issue command code CLR P2.0 ; RS=O for command CLR P2.1 ; R/W=O to write to LCD SETB P2.2 ; E=1 for H-to-L pulse CLR P2.2 ; E=O,latch in RET DATA_DISPLAY: ACALL READY ; is LCD ready? MOV P1, A ; lssue data SETB P2.0 ; RS=l for data CLR P2.1 ; R/W=O to write to LCD SETB P2.2 ; E=1 for H-to-L pulse CLR P2.2 ; E=0, latch in ٩٦ RET ٤٨

49 Example 13 (Continued): READY: SETB P1.7 ; Make P1.7 input port. CLR P2.0 ; RS=O access command Reg. SETB P2.1 ; R/W=1 read command Reg. ; Read command reg and check busy flag. BACK: SETB P2.2 ; E=1 for L-to-H pulse CLR P2. 2 ; E=0 for H- to-l pulse JB P1.7, BACK ; Stay until busy flag=o RET END ۱ بود LCD (P1.7) Data نيست پس از خواندن رجيستر فرمان اگر پرچم خوانده شده مشغول است وا ماده دريافت بايت Command يا ٩٧ مبدل ا نالوگ به ديجيتال ۸ کاناله EOC: End Of Conversion OE: Output Enable SC: Start Conversion ٩٨ ٤٩

50 پايان ٩٩ ٥٠