This file is a log of a session with the TOPS-20 interactive tutorial on twenex.org. It has been added to the SDF tutorials to make the content available on the World-Wide Web, but it is a much more effective learning experience to work through the tutorial interactively by logging-in to twenex.org and running the TOPS20 program.
===== Executive Summary =====
The tutorial introduces a number of useful keystroke commands for working with in the TOPS-20 EXEC environment.
| Output control |||
| | ^S | Pause output scrolling |
| | ^Q | Resume output scrolling |
| | ^O | Toggle output suppression |
| Command guidance |||
| | ESC | Command completion and guide words |
| | ? | Expected input guidance |
| Command line editing |||
| | ^R | Retype current line |
| | DEL (or BackSpace) | Erase previous character |
| | ^W | Erase previous word |
| | ^U | Erase current line |
| Program status and control |||
| | ^T | Session status |
| | ^C | Exit program (may need 2 or more) |
===== TOPS20 Tutorial Log =====
@tops20
Following is a brief explanation of some conventions of Tops-20.
Learning and remembering them will be a great help when exploring the
facilities on this system. If you are already familiar with Tops-20,
you should ^C out of this program. If not, you might want to take
notes.
The first things you should learn are the control characters ^S and
^Q. A "control character" is made by striking some letter WHILE
HOLDING DOWN the control key (marked "CTRL"). They are represented
in print by putting ^ before the letter. So ^S is made by striking S
while holding down the CTRL key. (S need not be typed in upper case.)
^S and ^Q are used to stop and start output (typing) to the terminal.
This is useful mostly on a CRT (video) terminal, where things you
want to look at have a habit of going off the top of the screen
before you can read it.
^S - stop output temporarily
^Q - continue stopped output
A ^S typed by you will be simulated now. (Type ^Q to continue.)
Very good! It is also possible (but we won't go into how here) to
have the line set up so that it automatically pauses at the end of an
uninterrupted page of output. Practice using ^S and ^Q every so
often throughout this lesson. (Remember: When output stops where you
wouldn't expect it to, the system is frequently just waiting for a
^Q.)
The next concept you should learn is that of ESCAPE and "?". Most
commands are given with words. You needn't type out the complete
command. A unique abbreviation is sufficient. After typing the
abbreviation, an ESCAPE (sometimes called ALTMODE, labeled "ESC" or
"ALT") will cause the system to type out the rest of the command
word. This is called recognition.
ESC - complete an abbreviated command
Here is an example - type an ESCAPE at the end of this example: