How do I use the GenericList parameter for HDL Coder Black Boxes?

Can you show an example of how to use the GenericList parameter for HDL Coder Black Boxes to define generics in VHDL?

I keep on getting errors such as:

For the block 'blackbox_test/toplevel/blackbox'
   Invalid GenericList parameter input '...'. 'The parameter input should be in the format of {{'GenericName', 'GenericValue', 'GenericType'}}.'
Eval error message: 'Invalid expression. Check for missing multiplication operator, missing or unbalanced delimiters, or other syntax error.
To construct matrices, use brackets instead of parentheses.'.'

Answer 1

[MathWorks Support Team]

Assuming that you are trying to generate the following GENERIC & GENERIC MAP in VHDL to pass to a subsystem with a BlackBox implementation:

 COMPONENT blackbox
    GENERIC( Sig1                         : STD_LOGIC;
             Sig2                         : STD_LOGIC_VECTOR(3 DOWNTO 0)
             );
-- snip --
u_blackbox : blackbox
    GENERIC MAP( Sig1 => '0',
                 Sig2 => "0000"
                 )

where 'Sig1' is a single bit signal assigned a value of '0' and 'Sig2' is a 4-bit vector signal assigned a value of "0000". 

The corresponding code to set the GenericList parameter for the Black Box subsystem in your model would be:

>> hdlset_param('blackbox_test/toplevel/blackbox','GenericList',...
    '{{''Sig1'',''''''0'''''',''STD_LOGIC''},{''Sig2'',''"0000"'',''STD_LOGIC_VECTOR(3 DOWNTO 0)''}}');

Alternatively, you can open the HDL parameters for the Black Box subsystem and enter the following string into the block mask:

{{''Sig1'',''''''0'''''',''STD_LOGIC''},{''Sig2'',''"0000"'',''STD_LOGIC_VECTOR(3 DOWNTO 0)''}}

Notice that to generate the string '0', the 0 is enclosed by 6 single quotes each.

To insert a numeric value defined in another variable, use "num2str":

>> myGainValue = 33;
>> str = ['{{''gainValue'',''' num2str(myGainValue) '''}}'];
>> hdlset_param('blackbox_test/toplevel/blackbox','GenericList',str);

For more information on "GenericList" and other Black Box parameters, refer to the following documentation:

https://www.mathworks.com/help/hdlcoder/ug/customizing-the-generated-interface.html 

How to validate the value passed to 'GenericList':

First, create variable 'char' containing the value in base workspace (where two single quotes will be parsed to one single quote):

>> char = '{{''Sig1'',''''''0'''''',''STD_LOGIC''},{''Sig2'',''"0000"'',''STD_LOGIC_VECTOR(3 DOWNTO 0)''}}'

char =

    '{{'Sig1','''0''','STD_LOGIC'},{'Sig2','"0000"','STD_LOGIC_VECTOR(3 DOWNTO 0)'}}'

And then evaluate the 'char' variable to get the cell array of character vectors:

>> genericsList = evalin('base',char);  % should not throw an "Invalid expression" error
>> genericsList{1,:}
ans =
  1×3 cell array
    {'Sig1'}    {''0''}    {'STD_LOGIC'}

ans =
  1×3 cell array
    {'Sig2'}    {'"0000"'}    {'STD_LOGIC_VECTOR(3 DOWNTO 0)'}