On 7/24/11 10:41 PM, Gregory Woodbury wrote:
On Mon, Jul 25, 2011 at 12:52 AM, yudi v <yudi.tux(a)gmail.com
No it's not my homework, just curious.
I looked at that link before posting.
what confused me was the DEL key code. Usually the first 32
characters are control characters but the wiki article clubs DEL
with the control characters where as it's assigned the last code
in the table. That's after the printable characters.
That's why I posted here to get a confirmation.
It's history. The DEL code was all holes punched in paper tape
(8-level) that was used to RUBOUT a character in error.
Teletype and papertape systems were programmed to ignore the 0xFF
code. When ASCII was formalized, the code for DEL
was firmly in use as a control character and papertape was still in
use. The various other "control" codes were used for various
esoteric paper tape storage methodologies and later for 8-bit wide
magnetic tape systems.
And it was carried over to 8 bit tape as well as BAUDOT (sp) code tape.
Great thing too. It was also used on punch cards.
Yep, I was around in those days and did a lot with paper tape and an
HP-3000 BASIC computer.
And one of the ways to create that code today is to use the SHIFT +
BACKSPACE combination in PuTTY, at least the way I configure it.