[Simh] Gah! ascii don't work??!

From: Ashley Carder <wacarder_at_usit.net>
Date: Mon Oct 18 08:04:27 2004

> > Ron,
> > The way I always cleared the screen in Basic-Plus on RSTS on a VT50 or
> > VT52
> > terminal was:
> >
> > PRINT CHR$(155)+"H"+CHR$(155)+"J"
> >
> > The CHR$(155)+"H" positions the cursor in the top left of the screen
> > Then, the CHR$(155)+"J" clears the screen.
> >
> > This is all from memory. I haven't actually written that kind of code
> > since the late 1970s.
> >
> > Ashley
> >
>
> Works on the terminal.. while the terminal is pretending to be a vt52
>
> ... but now still fails on the osX/Terminal but
> that's ok because it probably has a non-op vt52 emulation....

One of Paul's comments reminded me of something that had temporarily
slipped my memory. Although what I told you earlier should work,
the more correct syntax is:

PRINT CHR$(155%)+"H"+CHR$(155%)+"J"

The % character indicates that the value of 155 is an integer rather than
a floating point. At times the folks on our system back in the 1970s
(myself included) would "cheat" and try to squeeze our source programs
into as little disk space as possible, since we were only allowed 15
blocks of disk storage on our RK05 based PDP-11/40 RSTS/E system.
We did bad things like remove spaces and sometimes % characters.

Ashley
Received on Mon Oct 18 2004 - 08:04:27 BST