Low-level language

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Quick Questions

Shade in the A or B circle for each question.

1. Which of these is a low-level language?

A Assembly language

B Python

2. A low-level language is close to...

A everyday English

B the instructions the CPU understands

3. In a low-level language, each instruction usually does...

A one simple CPU operation

B many complex tasks at once

4. Which statement is true?

A Machine code is a high-level language

B Machine code is a low-level language

5. Why are low-level programs harder for people to read?

A They use simple CPU-level instructions instead of English-like commands

B They are always written in a different alphabet

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
1LDA 5		ALow-level languages are close to the hardware, not to English, so they are harder for people to read.
210110000 01100001		BADD R1, R2
3Each low-level instruction is one simple CPU operation, such as adding two values		Ctotal = a + b -> LDA a / ADD b / STA total
4Low-level code is close to the hardware, so one high-level line becomes many instructions		DAssembly language is low-level, not high-level. Its mnemonics map closely to CPU instructions.
5Assembly language is a high-level language because it uses words		EAn assembly language instruction that loads a value into the CPU, so it is a low-level language
6Low-level languages are easy for people to read because they are close to English		FMachine code, the binary instructions the CPU understands directly

Definitions

low-level language

Fill in the Blanks

Complete each line of code by filling in the missing parts.

___ 10 ; load 10 into the accumulator

LDA 10 ___ 5 ; add 5 to the accumulator

LDA 10 ADD 5 ___ total ; store the result

LDA __ ; load twenty into the accumulator

STO total ___ ; stop the program

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A LDA 10

B AAD 11

C STO 12

D END

Question 2

A LOAD 20

B SUB 21

C STO 22

D END

Question 3

A LDA 5

B ADD 6

C STO 7,8

D END

Question 4

A 00000001 00002010

B 00000010 00001011

C 00000011 00001100

Question 5

A 00000001 00000101

B 00000010 00000110

C 0000011 00000111

D 11111111

Answer Key

Low-level language

Section A: Quick Questions

A — Assembly language

B — the instructions the CPU understands

A — one simple CPU operation

B — Machine code is a low-level language

A — They use simple CPU-level instructions instead of English-like commands

Section B: Match the Pairs

LDA 5 → An assembly language instruction that loads a value into the CPU, so it is a low-level language

10110000 01100001 → Machine code, the binary instructions the CPU understands directly

Each low-level instruction is one simple CPU operation, such as adding two values → ADD R1, R2

Low-level code is close to the hardware, so one high-level line becomes many instructions → total = a + b -> LDA a / ADD b / STA total

Assembly language is a high-level language because it uses words → Assembly language is low-level, not high-level. Its mnemonics map closely to CPU instructions.

Low-level languages are easy for people to read because they are close to English → Low-level languages are close to the hardware, not to English, so they are harder for people to read.

Section C: Definitions

low-level language — A programming language close to the CPU's instructions, such as machine code or assembly language. Each instruction is one simple CPU operation, so it is harder for people to read.

Section D: Fill in the Blanks

LDA 10 ; load 10 into the accumulator

LDA 10
ADD 5 ; add 5 to the accumulator

LDA 10
ADD 5
STO total ; store the result

LDA 20 ; load twenty into the accumulator

STO total
END ; stop the program

Section E: Spot the Error

B — The assembly mnemonic for adding is ADD, not AAD. Each mnemonic stands for exactly one simple CPU operation, so it must be spelled correctly. The line should be ADD 11.

A — In this assembly language the mnemonic that loads a value into the accumulator is LDA. LOAD is not a valid instruction. The line should be LDA 20.

C — A low-level instruction does one simple operation, so STO takes a single address. It cannot store to two places at once. The line should be STO 7.

A — Machine code is written only in binary, using 0s and 1s. The digit 2 is not allowed. The line should be 00000001 00001010.

C — Every machine code instruction here has an 8-bit opcode. This one is missing a bit, so the CPU would read it wrongly. The line should be 00000011 00000111.