---
title: "8085 ALP: multiplication table of a number"
subject: "Microprocessor"
chapter: 2
key: "semester_4/microprocessor:alp-8085-multiplication-table"
source: https://www.bctengineer.com/q/semester_4/microprocessor/alp-8085-multiplication-table
site: BCT Engineering
---

# 8085 ALP: multiplication table of a number

Microprocessor · Chapter 2: Programming with 8085 Microprocessor

- Asked in: 2072 Magh, 8 marks
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_4/microprocessor/alp-8085-multiplication-table
- Whole chapter: https://www.bctengineer.com/md/semester_4/microprocessor/chapter-2

## Question

Write a program for 8085 to generate multiplication table of a number stored at 8230H and store the generated table starting at 8231H. For example, if location 8230H has number 05H then store 05H at 8231H, 0AH at 8232H and so on.

## Short answer

Load the number from 8230H into A and B. Add B repeatedly to generate successive multiples. Store ten entries (n×1 to n×10) starting at 8231H; for n=05H the table is 05H, 0AH, 0FH, ..., 32H.

## Answer

**Assumptions:** the table has 10 entries (n x 1 to n x 10), and each entry fits in one byte (n up to 19H = 25). For n = 05H the table is 05, 0A, 0F, 14, ... 32H.

**Method:** no multiplication instruction is needed: start with A = n and add n repeatedly to get the next multiple.


```asm
        LDA 8230H       ; A = number n
        MOV B,A         ; B = n
        LXI H,8231H     ; HL -> first table location
        MVI C,0AH       ; 10 entries (n x 1 ... n x 10)
LOOP:   MOV M,A         ; store current multiple
        INX H
        ADD B           ; next multiple = previous + n
        DCR C
        JNZ LOOP
        HLT
```


**Result for n = 05H:** 8231H = 05H, 8232H = 0AH, 8233H = 0FH, ... 823AH = 32H.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. How does the program produce each next multiple of n without a multiply instruction?
   A. By rotating A left once for each entry
   B. By adding n (kept in B) to the previous multiple in A
   C. By incrementing A with INR A
   D. By adding the loop counter C to A
   Answer: B. B holds n, and ADD B adds n to the previous multiple each time, giving n, 2n, 3n and so on. (Key point: Multiples are made by repeated addition of n (ADD B))

2. What is the role of LXI H,8231H and INX H in the program?
   A. HL holds the number n read from 8231H
   B. HL counts the 10 entries of the table
   C. HL is the memory pointer: it starts at 8231H and moves to the next location after each MOV M,A
   D. HL holds the current multiple so it can be added to A
   Answer: C. HL points to the table location; MOV M,A stores the multiple there and INX H moves to the next address. (Key point: HL points to 8231H and is incremented after each store)

3. With n = 05H and C = 0AH, what is stored at 823AH?
   A. 32H (5 x 10 = 50)
   B. 50H
   C. 0AH
   D. 37H
   Answer: A. 823AH is the 10th entry, 5 x 10 = 50 decimal = 32H; a common mistake is to write 50 as 50H. (Key point: For n = 05H the table is 05, 0A, 0F ... 32H (10 entries))

## Related in Microprocessor

- [8086 ALP: multiplication table of a number](https://www.bctengineer.com/question.md?key=semester_4%2Fmicroprocessor%3Aalp-8086-multiplication-table) — Microprocessor, chapter 3
- [8085 ALP: count ones in upper nibble](https://www.bctengineer.com/question.md?key=semester_4%2Fmicroprocessor%3Aalp-8085-ones-upper-nibble) — Microprocessor, chapter 2
- [8085 ALP: square of ten numbers](https://www.bctengineer.com/question.md?key=semester_4%2Fmicroprocessor%3Aalp-8085-square-numbers) — Microprocessor, chapter 2
- [8085 ALP: add upper and lower nibbles](https://www.bctengineer.com/question.md?key=semester_4%2Fmicroprocessor%3Aalp-8085-add-nibbles) — Microprocessor, chapter 2
- [8085 ALP: divide two bytes](https://www.bctengineer.com/question.md?key=semester_4%2Fmicroprocessor%3Aalp-8085-divide-bytes) — Microprocessor, chapter 2
- [8085 ALP: compare two tables of 16-bit data](https://www.bctengineer.com/question.md?key=semester_4%2Fmicroprocessor%3Aalp-8085-compare-tables-1ffffh) — Microprocessor, chapter 2

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