Question

Multiplication can be thought of as repeated addition. Three times four is 4 added to itself 3 times. 1) Create an assembly program that multiplies two 8 bit integers (2's complement) together in your PIC, using the repeated summation technique 2) Add a feature to your program that detects if the answer is too big to hold in 8 bit 2's complement notation 3) The repeated summation algorithm is slow. In a previous homework we developed a technique for multiplying that used bit shifting, that significantly reduces the number of loop iterations needed. Write a PIC assembly program to multiply two 8 bit integers (2's complement) together using this technique. [Hint: be careful of the carry bit.] 4) Develop a PIC routine to perform integer division of two positive 8 bit (2's complement) numbers, using a repeated subtraction algorithm. Report both the quotient and the remainder. 5) Develop a PIC routine to perform integer division of two positive 8 bit (2's complement) numbers, using long division (adapted for binary numbers). Report both the quotient and the remainder

Can someone carefully explain and answer questions 1, 2, 3, 4 and 5 in detail, please!!!

Answer 1

I have implemented multiplication of two 8 bit numbers in 8051 keil_software using an algorithm involves shifting operations....

1 ORG 0000H 2 MOV B, #08H 3 MOV A, #03H 4 MOV R2 , #08H 5 MOV DPTR, #0000H 6 LOOP2:RRC A 7 MOV R3,A 8 JNC LoOP 9 MOV A, DPH 10 ADD A,E 11 MOV DPH,A 12 LOOP:CLR C 13 MOV A, DPH 14 RRC A 15Μον DPH, A 16 MOV A, DPL 17 RRC A 18 MOV DPL, A 19 MOV A,R3 20 DJNZ R2, LOOP2 21 END

Results : Resulted 16 bit number stored in DPTR register.

Cx00 Cbx08 Cx07 sp Cx07 sp_max dptr Cx0018 PC S 124 states 0.00006 sec 困psw CxD0

we can implement division by division,multiplication by repeated subtraction, addition respectively .(8085 software)

8 BIT DIVISION # ORG 2000H # BEGIN 2000H LHLD 2501 LDA 2503 MOV B,A MVI C,08 LOOP: DAD H MOV A,H SUB B C AHEAD MOV H,A INR L DCR C AHEAD: JNZ LOOP SHLD 2504 HLT # ORG 2501H ILSB OF DIVIDEND, MSB OF DIVIDEND, DIVISOR # DB9BH,48H,1AH

8 BIT MULTIPLICATION: PRODUCT 16-BIT # ORG 2000H # BEGIN 2000H LHLD 2501 XCHG LDA 2503 LXI H,0000 MVI C,08 LOOP: DAD H RAL JNC AHEAD DAD D AHEAD: DCR C JNZ LOOP SHLD 2504 HLT # ORG 2501H I LSB OF MULTIPLICAND, MSB OF MULTIPLICAND,MULTIPLIER # DB 84H,00H,56H