Regarding "fwrite" in matlab

The following lines are a part of my code.

fid=fopen('M1.txt','w');
fwrite(fid,k,'int16');
fclose(fid);

I would like know how to include a delimiter. I need the .txt file to have 16 bits per line since this data has to be read line by line for further processing.

Kindly help me with this at the earliest.

Thank you

Answer 1

[Titus Edelhofer]

O.K., I give it another try:

x = 42;
fprintf(fid, '%s\n', dec2bin(x, 16));

Is that what you need?

Titus

Answer 2

[Titus Edelhofer]

Hi Aparna,

are you sure you want to use fwrite? With fwrite you write binary data (open your M1.txt with an editor that can display HEX data). There is no "line" in a text file usually. Could it be that you want to use fprintf instead?

If this is not the case, you could just use fprintf for the delimiter, i.e., add

fprintf(fid, '\n');

Hope this helps,

Titus

[Aparna]

This file as to be imported into xilinx where a vhdl code will read data line by line.

I did as you suggested but it still does not work.

It provides the data in 1 single line as a continuous stream of bits.

I would be really glad if you could help me out with this.

[Titus Edelhofer]

Hi Aparna,

that's what I meant: I'm pretty sure you don't want the bits but "numbers". Try

k = 42;

fprintf(fid, '%d\n', k);

Does this what you need?

Titus

[Geoff]

Is the xilinx expecting Windows newlines? In that case you'll have to output CRLF, not just LF:

fprintf(fid, '%d\r\n', k)

[Titus Edelhofer]

Or use

fid=fopen('M1.txt','wt');

(note the 'wt' instead of 'w') to handle this automatically.

Titus

[Walter Roberson]

Not quite, Titus. Using 'wt' outputs CRLF only if you are running on an MS Windows operating system, which is information we are not given. Geoff's suggestion of \r\n with 'w' is needed if the generating code might be running on something other than MS Windows.

[Aparna]

Thank you!!

But %d prints it as decimal.. is there any way to print it as a 16 bit values?

i tried using %s: which is a string of characters but it did not work.

The following line is what i used:

fprintf(fid, '%s\r\n', k,'int16')

I need it as a 16 bit binary value which should be imported into Xilinx where it gets read bit by bit. Hence i have to save the file as 0's and 1's.

[Asadullah]

Try %u instead of %d. visit http://www.mathworks.co.uk/matlabcentral/answers/32703-regarding-fwrite-in-matlab to read more about it.

[Walter Roberson]

That link leads to this question.