Problem with TextIO

[Rob Keiber]

Hi

I get the following error with the code fragment beneath, can anybody
tell me what is wrong?

Error: Subprogram write is "ambigious"
Error: Type error resolving function call: write.

library IEEE;
use IEEE.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
use std.textio.all;
....

process(clk)
variable s : line;
begin
...
write(s,"Test 1 - ");
write(s,"\n");
writeline(output,s);
...

Many thanks,
Rob

 

[Nicolas Matringe]

Rob Keiber a écrit :

Hi

I get the following error with the code fragment beneath, can anybody
tell me what is wrong?

Error: Subprogram write is "ambigious"
Error: Type error resolving function call: write.

library IEEE;
use IEEE.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
use std.textio.all;
....

process(clk)
variable s : line;
begin
...
write(s,"Test 1 - ");
write(s,"\n");
writeline(output,s);
...

For some reason (if somebody could explain, it is still unclear to me)
it is not clear what type your litteral constants are.
Try :
write (s, string'("Test 1 - "));

Nicolas

 

[Rob Keiber]

For some reason (if somebody could explain, it is still unclear to me)

it is not clear what type your litteral constants are.
Try :
write (s, string'("Test 1 - "));

Nicolas

Thanks Nicolas it works now for the compiling. However, the line

writeline(output,s);

doesnt output anything on the ModelSim Console. is this probably not
working with Modelsim 5.7d or is there another issue?

Cheers,
Rob

 

[Thomas Stanka]

I get the following error with the code fragment beneath, can anybody
tell me what is wrong?

write(s,"Test 1 - ");

You need to qualify the string to distinguish between string and
vector.

write(s, string'("Test 1 - "));

BTW the writeline command inserts a CR at line end. I don't think VHLD
supports "\n".

regards Thomas

 

[Alain]

Hello,

Try :

....
write(s,string'("Test 1 - "));
write(s,string'("\n"));
....

Regards

 

[ALuPin]

Are you sure that your process ever gets to the lines

write(s,"Test 1 - ");
write(s,"\n");
writeline(output,s);

?

Maybe some "wait until" condition before is not satisfied.

Use some test signal to proof that ...

Rgds
Andre

 

[Tricky]

For some reason (if somebody could explain, it is still unclear to me)
it is not clear what type your litteral constants are.
Try :
   write (s, string'("Test 1 - "));

Nicolas

Basically, the string could be either a bit_vector or a string, and
the compile doesnt know which it is as it does not (and cannot)
evaluate the contents of the string.

doesnt output anything on the ModelSim Console. is this probably not
working with Modelsim 5.7d or is there another issue?

In 6.1g (and I assume older versions): When you start a simulation in
modelsim, it gives you the option to write to a file instead of the
console. (Under TEXTIO files, STD_INPUT and STD_OUTPUT). Make sure you
havent set these to something (and hence writing into/out them).

Also, I notice you've got: write(s,"\n");
This does not add a newline character, but is the literals '\' and
'n'. to write a newline character you need to use: write(s, LF); But
the writeline() function already does that for you, so in effect you'd
just be adding an extra blank line.
There is no escape character in VHDL like in C, which makes putting
the " character into a string a pain (please someone correct me if Im
wrong).

 

[Martin Thompson]

There is no escape character in VHDL like in C, which makes putting
the " character into a string a pain (please someone correct me if Im
wrong).

Just put double-double quotes in:

report "Look, a "" in my message";

I can't remember where learned that nugget from (but I bet not from
reading the LRM

Cheers,
Martin