Answers Database
FPGA Express VHDL: Which libraries are needed for std_logic_vector addition/subtraction?
Record #4377
Product Family: Software
Product Line: Synopsys
Product Part: FPGA Express
Product Version: 2.1.1
Problem Title:
FPGA Express VHDL: Which libraries are needed for std_logic_vector addition/subtraction?
Problem Description:
Urgency: Standard
General Description:
When trying to add/subtract with std_logic_vectors, the following error will
be returned if the correct libraries are not used:
Error L23/C0 : #0 Error: <file>.vhd line <x>
Type mismatch on left and/or right operand of binary operator. (VSS-523)
Which libraries are needed for std_logic_vector addition/subtraction?
Solution 1:
For signed logic_vectors use the following libraries:
library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.std_logic_signed.all;
Solution 2:
For unsigned logic_vectors use the following libraries:
library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.std_logic_unsigned.all;
End of Record #4377 - Last Modified: 08/05/98 13:12 |
