error about 'can not have such operands in this context'

[Zhi]

error:" HexImage can not have such operands in this context.
IN mode Formal VALUE of write with no default value must be
associated with an actual value.
DecImage can not have such operands in this context.
IN mode Formal VALUE of write with no default value must be
associated with an actual value."

<HexImage> and <DecImage> are defined in the package "Image_Pkg." ,
can transfer 'signed' to 'string'.
--===========================================
function HexImage(In_Image : Signed) return String is
begin
return HexImage(Image(In_Image));
end HexImage;
--
function Image(In_Image : Signed) return String is
begin
return Image(Std_Logic_Vector(In_Image));
end Image;
--
function Image(In_Image : Std_Logic_Vector) return String is
variable L : Line; -- access type
variable W : String(1 to In_Image'length) := (others => ' ');
begin
IEEE.Std_Logic_TextIO.WRITE(L, In_Image);
W(L.all'range) := L.all;
Deallocate(L);
return W;
end Image;
--============================================
main program
--==================================
library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_arith.all;
use ieee.std_logic_textio.all;
use IEEE.Numeric_Std.all;

use std.textio.all;

library unisim;
use unisim.vcomponents.all;
--=======================================
library work;
use work.complex_pkg.all;
use work.Image_Pkg.all;
--=======================================
entity Complex is
end Complex;
--=======================================
architecture Complex_a of Complex is
signal A_s : A2x2C32_Typ;
signal B_s : A2x2C32_Typ;
begin -- Complex_a
Complex_Lbl : process
variable A : A2x2C32_Typ :=
( 1 => ( R => conv_signed(1,32),
I => conv_signed(2,32)),
2 => ( R => conv_signed(3,32),
I => conv_signed(4,32)),
3 => ( R => conv_signed(5,32),
I => conv_signed(6,32)),
4 => ( R => conv_signed(7,32),
I => conv_signed(8,32)));

variable B : A2x2C32_Typ :=
( 1 => ( R => conv_signed(10,32),
I => conv_signed(11,32)),
2 => ( R => conv_signed(12,32),
I => conv_signed(13,32)),
3 => ( R => conv_signed(14,32),
I => conv_signed(15,32)),
4 => ( R => conv_signed(16,32),
I => conv_signed(17,32)));

variable L:line;
file Result_f :text open write_mode is "result.txt";
--============================================
begin

write(L, string'("Multiplication"));
Writeline(Result_f, L);

write(L, "A.r=" & HexImage(A(1).R) & "A.I=" & HexImage(A(1).I));
writeline(Result_f,L);

write(L, "A.r ="& DecImage(A(1).R) & "A.I=" & DecImage(A(1).I));
writeline(Result_f,L);

write(L, "B.r=" & HexImage(B(1).R) & "B.I=" & HexImage(B(1).I));
writeline(Result_f,L);

write(L, "B.r=" & DecImage(B(1).R) & "B.I ="& DecImage(B(1).I));
writeline(Result_f,L);
wait;
end process;
end Complex_a ;

A(1).R/I actually is 'signed', why here has such an error information?
pleas help.

 

[Mike Treseler]

error:" HexImage can not have such operands in this context.
IN mode Formal VALUE of write with no default value must be
associated with an actual value.
DecImage can not have such operands in this context.
IN mode Formal VALUE of write with no default value must be
associated with an actual value." ....
A(1).R/I actually is 'signed', why here has such an error information?
pleas help.

Yikes. Here's how I do it.

-- Mike Treseler
-------------------------------
function uns2hexstr(arg : unsigned) return string is
-- Hex table look up
-- Note that we want one bit to be one hex digit, so we add 3 to
-- the bit length before subtracting the excess
-- A recursive function was used to eliminate messy loops
------------------------------------------------------------------------
constant hex_table : string := "0123456789abcdef";
constant max_len : natural := arg'length + 3;
constant adj_len : natural := hex_len(arg'length);
constant arg_pad_left : natural := abs(adj_len - 1);
constant arg_first_rt : natural := abs(adj_len - 4);
constant arg_rest_left : natural := abs(adj_len - 5);
variable arg_pad : unsigned(arg_pad_left downto 0) := (others => '0');
variable first_digit : unsigned(arg_pad_left downto arg_first_rt);
variable the_rest : unsigned(arg_rest_left downto 0);
-------------------------------------------------------------------------
begin
arg_pad(arg'length -1 downto 0) := arg; -- normalize
-- for two or more hex digits we recurse
if arg'length > 4 then -- 2 or more digits
first_digit := arg_pad(first_digit'range);
the_rest := arg_pad(the_rest'range);
return hex_table(1 + to_integer(first_digit)) -- first char
& uns2hexstr(the_rest); -- & rest of string later, same way
-- until "the rest" is zero or one hex digit
elsif arg'length = 0 then return "";
else
-- one hex digit: returning a char would be a type error
return "" & hex_table(1 + to_integer(arg));
-- note that (null string) & (table character) is a string
end if;
end uns2hexstr;

 

[Mike Treseler]

Yikes. Here's how I do it.

Oops. You might need this also:

function hex_len(arg : natural)
return natural is
constant max_len : natural := arg + 3;
begin -- never need to round up more than 3
return max_len - max_len mod 4; -- trim excess
end function hex_len;

-- Mike Treseler

 

[Zhi]

It might a little bit misunderstood.
--======================================--------
function HexImage(In_Image : Signed) return String is
begin
return HexImage(Image(In_Image));
end HexImage;
--
function Image(In_Image : Signed) return String is
begin
return Image(Std_Logic_Vector(In_Image));
end Image;
--
function Image(In_Image : Std_Logic_Vector) return String is
variable L : Line; -- access type
variable W : String(1 to In_Image'length) := (others => ' ');
begin
IEEE.Std_Logic_TextIO.WRITE(L, In_Image);
W(L.all'range) := L.all;
Deallocate(L);
return W;
end Image;

Here is one:

function HexImage(InStrg : String) return String is
subtype Int03_Typ is Integer range 0 to 3;
variable Result : string(1 to ((InStrg'length - 1)/4)+1) :=
(others => '0');
variable StrTo4 : string(1 to Result'length * 4) :=
(others => '0');
variable MTspace : Int03_Typ; -- Empty space to fill in
variable Str4 : String(1 to 4);
variable Group_v : Natural := 0;
begin
MTspace := Result'length * 4 - InStrg'length;
StrTo4(MTspace + 1 to StrTo4'length) := InStrg; -- padded with '0'
Cnvrt_Lbl : for I in Result'range loop
Group_v := Group_v + 4; -- identifies end of bit # in a group
of 4
Str4 := StrTo4(Group_v - 3 to Group_v); -- get next 4
characters
case Str4 is
when "0000" => Result(I) := '0';
when "0001" => Result(I) := '1';
when "0010" => Result(I) := '2';
when "0011" => Result(I) := '3';
when "0100" => Result(I) := '4';
when "0101" => Result(I) := '5';
when "0110" => Result(I) := '6';
when "0111" => Result(I) := '7';
when "1000" => Result(I) := '8';
when "1001" => Result(I) := '9';
when "1010" => Result(I) := 'A';
when "1011" => Result(I) := 'B';
when "1100" => Result(I) := 'C';
when "1101" => Result(I) := 'D';
when "1110" => Result(I) := 'E';
when "1111" => Result(I) := 'F';
when "ZZZZ" => Result(I) := 'Z';
when others => Result(I) := 'X';
end case;
end loop Cnvrt_Lbl;
--=================================================================
Actually I want 32 signed bit->8 bits string. As in the main
program:
-====================================================================
write(L, "A.r=" & HexImage(A(1).R) & "A.I=" & HexImage(A(1).I));
writeline(Result_f,L);