(VHDL) I'm Receiving an Error When Trying to Access an Array

[LRect]

Hello All,

I'm trying to output data inside an array to the 7-segment display on my DE1-SoC board.

Here are my variables:

display : out std_logic_vector (6 downto 0);

type bigDisplay is array (0 to 4, 0 to 6) of bit;

signal displayArray : bigDisplay;

Here is the code:

display <= displayArray (0, 6-0);

This is the error I receive:

Error (10381): VHDL Type Mismatch error at Final_Project.vhd(326): indexed name returns a value whose type does not match "std_logic_vector", the type of the target expression

So, I'm guessing I need to convert my bit array to output to the std_logic_vector? How should I do this?

[Abe · Accepted solution]

You can use the following to convert bit_vectors/ bit to std_logic_vector:

Use IEEE.STD_LOGIC_1164 package's function To_StdLogicVector

FUNCTION To_StdLogicVector ( b : BIT_VECTOR ) RETURN std_logic_vector;

[Pvand1]

Alternatevely you might use:

Type sevseg_t is std_logic_vector(6 downto 0); signal sevseg is array(0 to 4) of sevseg_t;

And then you can directly use the returned value of the array.

Also try using std_logic instead of bit asit helps to spot potential problems when simulating your design.