ASemester2 LAB ASSIGNMENT-EmbededSystemDesign · 2009. 11. 19. · Embedded System Design Lab Page - 7/21 Problem 5: Add the signed numbers found in internal RAM locations 25h, 26h

LAB ASSIGNMENT Embedded System Design

Student: ____________

ID: ________________

Class: ______________

Embedded System Design Lab Page - 2/21

CONTENTS �� 010

��

Problem: Page

1. Addressing modes ................................................. 3

2. Double number ..................................................... 4

3. Xor and compare ................................................... 5

4. Plus unsigned numbers at 3 memory location ....... 6

5. Plus unsigned numbers at 3 memory location ........ 7

6. Plus BCD numbers ........................................... 8

7. Loop ..................................................................... 9

8. Multiply .............................................................. 10

9. Divide ................................................................. 11

10. Define Byte DB and compare ........................... 12

11. Sorting values in memory locations .................. 13

12a. Linear search external memory ....................... 15

12b. Binary search external memory ....................... 17

13. Interrupt transmission ....................................... 18

14. Polling transmisstion ......................................... 19

15. Serial communication ....................................... 20

16. Input output ports, COM port communication ... 21


Problem 1:

Copy the byte in TCON to register R2 using at least four different methods.

a. Use the direct address for TCON

b. Use the direct address for TCON and R2

c. Use R1 as a pointer to R2 and use the address for TCON

d. Push the content of TCON into direct address

Code listing a:

mov 88h, #50h ; TCON address is 88h

mov R2, 88h ; copy content TCON from its direct address

Code listing b:

mov 02h, 88h ; copy direct addrect of TCON to direct address of R2

Code listing c:

mov R1, #02h ; R1 contains value 02h which is direct address of R2

mov @R1, 88h ; copy TCON to direct address that R1 point to

Code listing d:

push 88h ; push TCON to stack

pop 02h ; pop top of stack to direct addrect of R2


Problem 2:

Double the number in register R2, and put the result in registers R3 (high

byte) and R4 (low byte).

Code listing:

mov R2, #0F2H ; copy R2 content to A

mov A, R2 ; copy R2 content to A

mov R3, #0 ; clear R3

add A, R2 ; double R2

mov R4, A ; copy low byte result to R4

jnc over ; if CY = 0 then finish

mov R3, #1 ; if CY=1 then set 1 to R3 (high byte result)

over:

end

Results from executing the program


Problem 3:

Find a number that, when XORed to the register A, results in the number

3Fh in A.

Code listing:

mov R1,#0FFh ; copy initial maximum value to R1

again: mov A,#54h ; copy test value #54h to A

xrl A, R1 ; xor A with R1

dec R1 ; decrement R1

cjne A,#3Fh, again ; test if result = #3Fh

inc R1 ; finding number contains in R1

end

54h = 01010100 6Bh = 01101011 xor = 00111111 = 3Fh



Problem 4:

Add the unsigned numbers found in internal RAM locations 25h, 26h and

27h together and put the result in RAM location 31h(MSB) and 30h(LSB).

Code listing:

mov 25h,#0FFh ; copy test value #0FFh to address 25h

mov 26h,#0FAh ; copy test value #0FAh to address 26h

mov 27h,#0EEh ; copy test value #0EEh to address 27h

mov R1,#0 ; clear R1

clr C ; clear Carry

mov A,25h ; copy value from address 25h to A

add A,26h ; add value from address 26h to A

jnc next1 ; if CY=0 then add next value

inc R1 ; if CY=1 then increase R1

clr C ; clear Carry

next1: add A,27h ; add next value from address 27h to A

jnc next2 ; if CY=0 then report the result


next2: mov 30h,A ; copy LSB to address 30h

mov 31h,R1 ; copy MSB to address 31h

end



Problem 5:

Add the signed numbers found in internal RAM locations 25h, 26h and 27h

together and put the result in RAM location 31h(MSB) and 30h(LSB).

Code listing:

mov 25h,#+20 ; copy test value #+20 to address 25h

mov 26h,#-30 ; copy test value #-30 to address 26h

mov 27h,#+70 ; copy test value #+70 to address 27h




jb PSW.2,over ; if overflow flag OV=1 then cancelled




jb PSW.2,over ; if overflow flag OV=1 then cancelled





over:

end



Problem 6:

Add the BCD numbers found in internal RAM locations 25h, 26h and 27h

together and put the result in RAM location 31h(MSB) and 30h(LSB).

Code listing:

mov 25h,#37h ; copy test value #37h to address 25h






da A ; adjust A to BCD number




da A ; adjust A to BCD number





end



Problem 7:

Place any number in internal RAM location 3Ch and increment it until the

number equals 2Ah.

Code listing:

mov 3Ch,#20h ; test value in address 3Ch

mov R1,#3Ch ; R1 contains value #3Ch

again: mov A,@R1 ; copy value in address that R1 point to A

cjne A,#2Ah,next ; compare A with value #2Ah

sjmp over ; if equal then finish

next: inc @R1 ; increment value in address 3Ch

sjmp again ; repeat while not equal

over:

end



Problem 8:

Multiply the data in RAM location 22h by the data in RAM location

15h.Put the result in RAM Location 19h(LSB) and 1Ah(MSG).

Code listing:

mov 15h,#40 ; test value 1 in address 15h

mov 22h,#7 ; test value 2 in address 22h

mov A,15h ; copy test value 1 to A

mov B,22h ; copy test value 2 to B

mul AB ; multiply A with B

mov 19h,A ; copy LSB of result to address 19h

mov 1Ah,B ; copy MSB of result to 1Ah

end



Problem 9:

Divide the data in RAM Location 3Eh by the number 12h. Put the quotient

in R4 and remainer in R5

Code listing:

mov 3Eh,#29h ; test value #29h in address 3Eh

mov A,3Eh ; copy value in address 3Eh to A

mov B,#12h ; copy #12h to B

div AB ; divide A to B

mov R4,A ; copy quotient to R4

mov R5,B ; copy remainer to R5

end



Problem 10:

Define a number in external RAM using ‘DB’. Check whether the number

is even or odd. If it is even set C to 1, otherwise clear C.

Code listing:

org 500h ; at address 500h, define byte value 7h

data1: DB 7h ; 7h in external memory 500h

org 0

mov DPTR, #500h ; DPTR contain external address 500h

clr A ; clear A

movc A, @a+DPTR ; copy value from external memory to A

clr C ; reset Carry

rrc A ; rotate right A to carry

jb CY,odd ; if odd

setb C ; if even

sjmp over ; finish

odd:

clr C

over:

end



Problem 11:

Write a program to sort (ascending/descending) the array which is stored in

external RAM.

Code listing:

mov 30h,#4h ; test values put in address 30h-33h

mov 31h,#6h

mov 32h,#5h

mov 33h,#1h

mov R1,#30h

mov R7,#3 ; outer loop counter

mov R6,#4 ; inner loop counter

outerloop:

mov A,R1

mov R0,A

mov A,@R1 ;copy first value for each cycle

dec R6

mov 03h,R6

interloop:

clr c

inc R0 ; travel inner loop

mov 40h,@R0 ; use addr 40h for compare value

cjne A,40h,next ; cy=1 if a less than

sjmp nextloop

next: jnc exchange ; if cy=1 then swap

sjmp nextloop

exchange: mov 02h,A

mov A,@R0

mov @R0,02h

nextloop: nop

djnz R6,interloop

mov @R1,A

mov R6,03h

inc R1

djnz R7,outerloop

mov R4,30h ; display result in registers R4-R7

mov R5,31h

mov R6,32h

mov R7,33h

end


Problem 12a: Linear Search

Write a program for searching an element which is stored in external RAM

location between 0100h and 0200h. Also find out the address of the found

element. Address of the element will be stored in the register R6 (LSB) and

R7 (MSB). Return A=1 if element is found otherwise 0. Perform searching

using at least any two following techniques.

1. Linear Search

2. Binary search

3. even/Odd Search

Code listing(linear search):

mov DPTR,#100h ; DPTR point to address 100h external memory

mov A,#20h ; sample data

movx @DPTR,A ; copy sample data to 100h

mov DPTR,#123h ; DPTR point to address 123h

mov A,#15h ; sample data #15h

movx @DPTR,A ; copy sample data to 123h

mov DPTR,#100h ; start address to search

mov R1,#100 ; loop 100 times from address 100h to 200h

mov R0,#15h ; value need to find

again: movx A,@DPTR ; fetch value that DPTR point to

cjne A,0h,next ; compare content of A with R0

mov A,#1 ; if found

sjmp found ; find the address

next: inc DPTR ; not equal then loop next

djnz R1,again ; count number of loops

mov A,#0 ; not found

sjmp notfound ; finish

found:

mov R6,DPl ; identify low byte of found external memory location

mov R7,DPH ; identify high byte of found external memory location

notfound:

end


Problem 12b: Binary Search mov A,#100 ; initial value mov R3,#101 mov DPTR,#100 loop:

movx @DPTR,A ; initiate ;memory location from 100 ;to 200 values from 100-201

inc A inc DPTR djnz R3,loop ; repeat 101s mov R0,#123 ; find this value

; #7Bh(test value) mov DPTR,#100 mov R1,#100 ; each loop divide

; 2 and plus to DPTR mov B,#2 mov A,R1 div AB mov R1,A mov A,DPL add A,R1 mov DPL,A ; DPTR point to

; middle element mov A,DPH jnc next1 inc A mov DPH,A next1: movx A,@DPTR ; copy value

;of middle element to A clr C cjne A,0h,next2; compare

;with value #7Bh in R0 mov R6,DPL ; store LSB mov R7,DPH ; store MSB sjmp over ; equal finish next2:

jnc left ; dest < source then CY=1 mov A,R1 ; DPTR move right mov B,#2 div AB jnz A_e_0 mov A,#1 A_e_0: mov R1,A mov A,DPL ; calculate ; position of middle element add A,R1 mov DPL,A mov A,DPH jnc next3 inc A mov DPH,A next3: sjmp next1 left: clr C ; DPTR move left mov A,R1 mov B,#2 div AB jnz A_e_02 A_e_02: mov A,#1 mov R1,A mov A,DPL ; calculate ; position of middle element subb A,R1 mov DPL,A mov A,DPH jnc next4 inc A mov DPH,A next4: sjmp next1 over: end



Problem 13: Interrupt transmission

Write a program for transmitting character using following method

Interrupt Transmission

Code listing:

When timer 1 interrupt occurs then increasing A and transmit it to P1

org 0

ljmp start

org 001Bh ; timer 1 interrupt vector table

inc A ; increment A

mov P1,A ; copy A to P1

reti ; return from interrupt service routine

org 40h

start: mov TMOD,#20h ; timer 1, mode 2 (8-bit auto-reload)

mov TH1,#0 ; initial value

mov IE,#10001000b ; enable timer 1

setb TR1

again: sjmp again ; loop forever and wait timer 1 interrupt

end



Problem 14: Polling transmission

Write a program for transmitting character using following method Polling

Transmission

Code listing:

mov TMOD,#01h ; timer 0, mode 1 (16-bit timer)

repeat: mov TH0,#0 ; initial value

mov TL0,#10 ; iniital value

setb TR0

again: jnb TF0, again ; monitor timer flag 0

clr TR0 ; stop timer 0

clr TF0 ; clear timer flag 0

inc A ; increasing A

mov P0,A ; copy A to port P0

sjmp repeat ; repeat forever

end



Problem 15: Serial Communication

Write a program that takes the character in the A register, transmits it,

delays for the transmission time, and then returns to the calling program

with following specifications

a. Timer 1 must be used to set the baud rate 2400

b. The delay for one 10-bit character is 1,000/240 or 4.16 milliseconds

c. The timer 1 should generate baud rate at SBUF

Code listing:

Assuming XTAL = 11.0592 MHz

Machine cycle = 11.0592 MHz / 12 = 921.6 kHz

Cycle time = 1 / 921.6 kHz = 1.085 µs

UART frequency = 921.6 kHz / 32 = 28800 Hz

Use timer 1 mode 2 (8-bit auto-reload)

To set baud rate 2400:

28800/2400 = 12 then assign TH1=#-12

Time delay for one 10-bit character is 4.16 ms (1000/240)

4160/1.805 = 3834

a. Timer 1 must be used to set the baud rate 2400

mov TMOD,#20h ; timer 1, mode 2 (8-bit auto-reload)

mov TH1,#-12 ; baud rate 2400

setb TR1 ; start timer 1

mov SBUF,A ; copy content of A to SBUF for transmit

wait: jnb TF1, wait ; monitor TF1

clr TR1 ; stop timer 1

clr TF1 ; clear timer flag 1

b. The delay for one 10-bit character is 1,000/240 or 4.16 milliseconds

65536 – 3834 = 61702 = F106h

mov TMOD,#10 ; timer 1, mode 1 (16-bit timer)

mov TH1,#0F1h ; initial high byte value

mov TL1,#6h ; initial low byte value


mov SBUF,A ; copy content of A to SBUF for transmit

wait: jnb TF1,wait ; monotor TF1

clr TR1

clr TF1


Problem 16:

Write a 8051 program to read data from port 1 and write to port 2

continuously while giving a copy of it to serial COM port to be transferred

serially. Specification:

i. Baud rate 9600/2400

ii. XTAL 11.0592

iii. write a single Interrupt routine for TI & RI

Code listing:

org 0

ljmp start

org 0023h ; interrupt vector table for serial

ljmp serial

org 30h ; by-pass interrupt vector table

start: mov P1,#0FFh ; P1 becomes input port

mov P1,#11001100B ; test value at P1

mov TMOD,#20h ; timer 1, mode 2 (auto-reload)

mov TH1,#-3 ; set baud rate 9600

mov SCON, #192 ; serial mode 1, 8-bit, 1 start bit, 1 stop bit

mov IE,#10010000B ; enable serial interrupt


repeat: mov A,P1 ; copy P1 to A

mov P2,A ; issue A to P2

mov SBUF,A ; serial transmit A to COM port

cpl A ; complement A for testing

mov P1,A ; assign new value for P1

sjmp repeat ; do it continuously

serial:jnb TI,serial ; interrupt service routine

clr TI ; clear TI

reti


Documents

ASemester2 LAB ASSIGNMENT-EmbededSystemDesign · 2009. 11. 19. · Embedded System Design Lab Page - 7/21 Problem 5: Add the signed numbers found in internal RAM locations 25h, 26h