[U-Boot] [PATCH] serial: lpc32xx: send CR before LF

[Wolfgang Denk <wd@denx.de>]

Dear Marek Vasut,

In message <201311301642.36531.marex@denx.de> you wrote:
> Dear Vladimir Zapolskiy,
> 
> > For LPC32XX high-speed UART it is required to send a carriage return
> > symbol along with line feed.
> 
> Why ?

Because we are actually emulating a classical type writer here, and to
start printing at the beginning of a new line requires two separate
actions: performing a line feed (i. e. scrolling the paper one line
up) and a crriage return (i. e. repositioning the drum such that the
next character will be printed in column 1.

In the strict sense, the ASCII characters represent the line feed and
'\r' the carriage return, respectively.  To print the equivalent of
the "new line" as it is interpreted by the C standard, we have to
translate the single C character into a two-character sequence.  You
can trace this back to the very beginnings of Unix; you can see the
same in Unix version 6 drivers, for example.

Best regards,

Wolfgang Denk

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