Reading hex data from file

Hi!

I have got text file with data wrote in this manner:

.........
01 04 A2 FC 10 D0 E4 C2
0A C3 FF 9A D2 E1 00 00
.........


each 2-sign value is a hex value of std_logic_vector(7 downto 0), and it
should be connected with data vector in my project like this:

data(7 downto 0) <= (2-sign value from text file);


how can I do that?
have you got a similiar vhdl example witch I can use?

Thanks for any help

Paul

magik

Hi,

Simple;
OTOMH (not tested, so you have a little work left

use std.textio.all;
use ieee.std_logic_textio.all; -- Synopsys

readline(L, File_handle);
for i in 1 to 8 loop
hread (L, vData); -- variable vData : std_logic_vector(Data'range);
Data <= vData;
-- wait some etc...
end loop;


and do this while you've not reached the end of file.
Voilà


magik wrote:
> Hi!
>
> I have got text file with data wrote in this manner:
>
> ........
> 01 04 A2 FC 10 D0 E4 C2
> 0A C3 FF 9A D2 E1 00 00
> ........
>
>
> each 2-sign value is a hex value of std_logic_vector(7 downto 0), and it
> should be connected with data vector in my project like this:
>
> data(7 downto 0) <= (2-sign value from text file);
>
>
> how can I do that?
> have you got a similiar vhdl example witch I can use?
>
> Thanks for any help
>
> Paul
>
>

info_

info_ wrote:

> Hi,
>
> Simple;
> OTOMH (not tested, so you have a little work left
>
> use std.textio.all;
> use ieee.std_logic_textio.all; -- Synopsys
>
> readline(L, File_handle);
Ooops !
readline (File_handle,L); -- indeed


Bert Cuzeau

info_

Thanx Bert!!

What if some of my lines are not exactly with 8 2-hex ??

ok, in real the file looks like this:

---------------------------------
COMAND_A
01 04 A2 FC 10 D0 E4 C2
0A C3 FF 9A D2 E1 00 00
(empty line or comment)
COMAND_B
01 04 A2
---------------------------------

I will start from checking first line witch should cover string and I will
decide what to do. Of course at this moment I will use read(L, string_var);
where string_var is STRING type. After this I will read data... how can I
assume that there is no more data in present line or the line is empty or
has no-hex (0-9, A-F) objects??


Paul

magik

magik wrote:

> Thanx Bert!!
>
> What if some of my lines are not exactly with 8 2-hex ??
>
> ok, in real the file looks like this:
>
> ---------------------------------
> COMAND_A
> 01 04 A2 FC 10 D0 E4 C2
> 0A C3 FF 9A D2 E1 00 00
> (empty line or comment)
> COMAND_B
> 01 04 A2
> ---------------------------------
>
> I will start from checking first line witch should cover string and I will
> decide what to do. Of course at this moment I will use read(L, string_var);
> where string_var is STRING type. After this I will read data... how can I
> assume that there is no more data in present line or the line is empty or
> has no-hex (0-9, A-F) objects??
>
>
> Paul
>
>

Can test L(1), but your example is quite unfriendly as "C" is a
valid hex character
Why not use a semicolumn for non-data (& comments) lines ?

Testing L'length is recommended. Less than 2 is hopeless
for hreading a byte. (it gets easily rid of blank lines too)

Could use the "safe" version of read & test the boolean to see if the
extraction went okay or not.

Writing a robust data parser in VHDL isn't terribly exciting,
but it isn't very difficult either.
Once you'll have yours, keep it : it's very useful and resusable code.

Bert Cuzeau

info_

Thanx again !!

OK my test model is working, but how can I finish testing ?
For now, when the end of the input text file is reached my AHDL is crashing
down...


Paul

magik

magik wrote:
> Thanx again !!
>
> OK my test model is working, but how can I finish testing ?
> For now, when the end of the input text file is reached my AHDL is crashing
> down...
AHDL ? ! you mean VHDL ?

while not ENDFILE(F) loop
-- process the file
end loop;
should do the trick.


Bert Cuzeau

Bert Cuzeau