Concatenation operator (&) in VHDL - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to concatenate two std_logic_vectors.

VHDL

result <= vector1 [1] vector2;

Drag options to blanks, or click blank then click option'

A&

B+

C*

D|

Attempts:

3 left

💡 Hint

Common Mistakes

Using '+' instead of '&' for concatenation.

Using '|' which is not valid for concatenation in VHDL.

In VHDL, the concatenation operator is '&'. It joins two vectors end to end.

2fill in blank

medium

Complete the code to concatenate a single bit 'a' with a 3-bit vector 'b'.

VHDL

output_vector <= a [1] b;

Drag options to blanks, or click blank then click option'

A*

B+

C&

D-

Attempts:

3 left

💡 Hint

Common Mistakes

Using arithmetic operators like '+' or '-' instead of '&'.

The '&' operator concatenates a single bit with a vector in VHDL.

3fill in blank

hard

Fix the error in the concatenation of two std_logic_vectors 'x' and 'y'.

VHDL

combined <= x [1] y;

Drag options to blanks, or click blank then click option'

A+

B||

C*

D&

Attempts:

3 left

💡 Hint

Common Mistakes

Using '||' which is not a VHDL operator.

Using '+' which is for arithmetic, not concatenation.

The correct concatenation operator in VHDL is '&'. '+' or '||' are invalid here.

4fill in blank

hard

Fill both blanks to concatenate 'a' and 'b' and then concatenate the result with 'c'.

VHDL

final_vector <= (a [1] b) [2] c;

Drag options to blanks, or click blank then click option'

A&

B+

C*

D|

Attempts:

3 left

💡 Hint

Common Mistakes

Using '+' or '*' instead of '&' for concatenation.

Use '&' to concatenate vectors step by step in VHDL.

5fill in blank

hard

Fill all three blanks to create a 6-bit vector by concatenating 'a', 'b', and 'c' in order.

VHDL

six_bit_vector <= a [1] b [2] c [3] "00";

Drag options to blanks, or click blank then click option'

A&

B+

C*

D|

Attempts:

3 left

💡 Hint

Common Mistakes

Using arithmetic or bitwise operators instead of '&'.

Use '&' to concatenate all parts into one vector in VHDL.