Concatenating bits in VHDL

Question

How do you concatenate bits in VHDL  I m trying to use the following code   Case b0  amp  b1  amp  b2  amp  b3 is        and it throws an error  Thanks

User · Answer

You are not allowed to use the concatenation operator with the case statement  One possible solution is to use a variable within the process   process b0 b1 b2 b3     variable bcat   std logic vector 0 to 3   begin    bcat    b0  amp  b1  amp  b2  amp  b3     case bcat is       when  0000    gt  x  lt   1        when others   gt  x  lt   2     end case  end process

User · Answer

Here is an example of concatenation operator   architecture EXAMPLE of CONCATENATION is    signal Z BUS   bit vector  3 downto 0      signal A BIT  B BIT  C BIT  D BIT   bit  begin    Z BUS  lt   A BIT  amp  B BIT  amp  C BIT  amp  D BIT  end EXAMPLE

User · Answer

You are not allowed to use the concatenation operator with the case statement  One possible solution is to use a variable within the process   process b0 b1 b2 b3     variable bcat   std logic vector 0 to 3   begin    bcat    b0  amp  b1  amp  b2  amp  b3     case bcat is       when  0000    gt  x  lt   1        when others   gt  x  lt   2     end case  end process

User · Answer

The concatenation operator   amp   is allowed on the right side of the signal assignment operator   lt     only

User · Answer

Here is an example of concatenation operator   architecture EXAMPLE of CONCATENATION is    signal Z BUS   bit vector  3 downto 0      signal A BIT  B BIT  C BIT  D BIT   bit  begin    Z BUS  lt   A BIT  amp  B BIT  amp  C BIT  amp  D BIT  end EXAMPLE

User · Answer

Here is an example of concatenation operator   architecture EXAMPLE of CONCATENATION is    signal Z BUS   bit vector  3 downto 0      signal A BIT  B BIT  C BIT  D BIT   bit  begin    Z BUS  lt   A BIT  amp  B BIT  amp  C BIT  amp  D BIT  end EXAMPLE

User · Answer

The concatenation operator   amp   is allowed on the right side of the signal assignment operator   lt     only

User · Answer

Here is an example of concatenation operator   architecture EXAMPLE of CONCATENATION is    signal Z BUS   bit vector  3 downto 0      signal A BIT  B BIT  C BIT  D BIT   bit  begin    Z BUS  lt   A BIT  amp  B BIT  amp  C BIT  amp  D BIT  end EXAMPLE

User · Answer

The concatenation operator   amp   is allowed on the right side of the signal assignment operator   lt     only

User · Answer

The concatenation operator   amp   is allowed on the right side of the signal assignment operator   lt     only

[concatenation] Concatenating bits in VHDL

Examples related to concatenation

Examples related to vhdl