Re: gEDA: Problem with parametrized constant widths in VBS

[Jimen Ching <jching-at-NOSPAMflex_dot_com>]

On Mon, 17 Apr 2000, Stephen Williams wrote:
>ahvezda@seul.org said:
>> With such definitions, the "state_reg = ADR;" statement results in
>> setting state_reg to 3
>   parameter        ws=3;
>   reg [ws-1:0]     state_reg;
>   parameter        IDLE = ws'h0, ADR = ws'h7, RD1 = ws'h6, RD2 = ws'h3,
>                    WR1 = ws'h4, WR2 = ws'h5 ;
>Just to clarify, you are saying that the subsequent statement
>	state_reg = ADR;
>	$display("state_reg = %b", state_reg);
>
>causes the output "state_reg = 011"? What happens if you replace "ADR = ws'h7"
>with "ADR = 3'h7"?

I get 7.  My question is, can a parameter be used as part of the symbols
that make up the decimal_number terminal (YACC speak)?  According to the
IEEE-1364, I am supposed to look for a 'unsigned_number' where 'ws' was
used.  A parameter_identifier is considered a 'constant_primary' terminal.  
Thus, it is not a valid construct for a decimal_number.

I think VBS is doing the right thing, and the code above is wrong.  Anyone
have opinions?

--jc
--
Jimen Ching (WH6BRR)      jching@flex.com     wh6brr@uhm.ampr.org