Search code examples
stringintegertype-conversionvhdl

How to convert a string to integer in VHDL?

I am loading text data into a VHDL test bench and I want to convert input strings into integer values.

eg: "123" => 123

Can someone recommend a "best" way of converting strings to integers in VHDL?

Solution

  • readline and read functions should achieve what you are looking for.

    Basically:

    1. Open your file
    2. Use readline to get the next line from file into a line buffer
    3. Use read to parse the line buffer to useful data
    4. (Optional) convert the parsed value as necessary

    Code Snippet:

    library STD;
use std.textio.all;
...
variable File_Name         : string;
file my_file               : text; 
variable lineptr           : line;
variable temp              : integer;
...
file_open(my_file, File_Name, read_mode); -- open the file
readline(my_file, lineptr); -- put the next line of the file into a buffer
read(lineptr, temp); -- "parse" the line buffer to an integer
-- temp now contains the integer from the line in the file
...