Pete Turnbull <pete_at_dunnington.u-net.com> wrote:
> All the lines have two spaces between the line number and the code.
> All, that is, except for a few that have an '_at_' in place of the second
> space. Is that significant (does it mean "ignore this" or something?)
> or is it just an artifact of a noisy Teletype line? (The listing
Noisy line, most likely. I don't think it has any significance.
> What does '14 in a PRINT statement, in front of a quoted string, mean
> (eg in PRINT '14"SULU")? I wondered if it were something like PRINT
> TAB(14)"... but there are TAB()s elsewhere. A control character,
> perhaps? If cursor or screen control, are they octal or decimal (I'd
> guess decimal) and is there a table anywhere?
The leading single quote outside double quotes is how HP BASIC (2000
and 3000) represent a non-printable character in a string constant.
So '14 is decimal 14 as a character, or control-N.
On an HP 262x or 264x terminal this would be done to switch away from
an alternate character set (which would be switched to by control-O or
'15 and selected by an escape sequence '27"(" followed by "_at_" for the
base set, "A" for the math set, and "B" for the line drawing set).
> What exactly do the first two parameters to the ENTER command do? They
> always seem to have three variables (eg ENTER T2,T,X$).
I don't recall the details clearly, I'm thinking one is a limit in
seconds on the time the user has to reply, and I'm thinking the other
is used to return the time it took the user to enter the reply.
-Frank McConnell
Received on Tue Nov 11 2003 - 00:50:06 GMT