FPGA CASE When Hex range data syntax

[ralphLunt]

Syntax for range of Hex values in the when line of a CASE statement.
e.g. When = X"03" to X"F9" => ....
Thanks

 

[dpaul]

I did not understand the question. Specifically how the sentence in English is formulated.

 

[ralphLunt]

Syntax for range of Hex values in the when line of a CASE statement.
e.g. When = X"03" to X"F9" => ....
Thanks

This is the code I'm evaluating for syntax
Case Sel is
When = X"03" to X"F9 => code to execute
When others .....
What is the correct syntax for the line above X"03" to X"F" , or X("03 to F9", or another format

 

[ads-ee]

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Code VHDL - [expand]
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case sel is
  when X"03" | X"04" | X"05" | X"06" | X"07" | X"08" | X"09" | X"0A" ......etc
when others .....

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If you have such a huge range of values you are testing against it is probably better if you use an if statement

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Code VHDL - [expand]
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if sel >= X"03" and sel <= X"F9" then
  ....
end if;

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[FvM]

You didn't mention the type of sel. The case statement can use discrete ranges with "to" in the choice, but only for integer case expressions.

If sel is e.g. an unsigned type, you can write

case to_integer(sel) is
  when 16#03# to 16#f9# =>
  when others =>
end case;

Similarly, you can cast std_logic_vector case expressions to_integer(unsigned( )).