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Re: [f-cpu] binary streams

Hi #2,

On Thu, Sep 13, 2001 at 12:52:57AM +0200, Yann Guidon wrote:
> given a text input file, simili will insert 0xD, 0xA pairs
> for carriage returns. Well, it's a MSDOS thing.
> Worse : simili "interprets" the input characters and particularly :
> it stops on a "EOF" character (i don't know which) while
> Vanilla copies texto the input to the output.

EOF used to be ^Z (decimal 26); I guess it's still that way.

> This is not revelant for the text i/O but i want to
> handle "binary" files, that is : whatever the data is.
> the different behaviours of the tools almost gave me headaches.
> anyone can help ?

That's easy to handle in C -- fopen(file, "rb") should do the trick --
but I don't know what to do in VHDL.  Perhaps you can do something like

	type octet is 0 to 255;
	type octet_stream is file of octet;

If it still stops at a ^Z, I would consider that a bug in Simili.
But you'll probably have to write a completely new set of I/O routines
for the `octet' type.

On the other hand, binary files are evil anyway because they're not
portable (imagine you had to transfer them to a big-endian box, like
SPARC).  Better use a `compact' ASCII representation (e.g.  hexadecimal
numbers).  It will have a 2:1 overhead, but it's portable, and also
readable/editable by humans.  Another portable and even more compact
(but unreadable) encoding is base64 (used by MIME, for example).

 Michael "Tired" Riepe <Michael.Riepe@stud.uni-hannover.de>
 "All I wanna do is have a little fun before I die"
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