home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Turnbull China Bikeride
/
Turnbull China Bikeride - Disc 2.iso
/
STUTTGART
/
FROMUTS
/
ARC100
/
!Arc100
/
!ReadMe
next >
Wrap
Text File
|
1991-01-03
|
10KB
|
220 lines
Documentation for Arc100 Beta-Test 2.2 - a PD VT100 Terminal Emulator
---------------------------------------------------------------------
All code and documentation is the exclusive copyright of Richard K. Lloyd,
but it may be freely distributed and is completely in the Public Domain.
ATTENTION !
Although this program has (finally) been released into the Public Domain,
it is strictly beta-test and may contain some minor flaws. The author accepts
no responsibility if these flaws cause any problems for the user whatsoever.
Please report any problems/bugs to the address at the end of this document -
XON/XOFF at high baud rates is suspect at the moment...apologies for this.
Introduction
------------
Arc100 is a VT100 terminal emulator I wrote a while ago and never released
into the PD because RISC OS caused it to stop handling XON-XOFF correctly.
I finally corrected this during the Christmas 1990 break - I tracked it down
to the event vector routine I had written taking too long to flash the custom
cursor :-)
Supplied Features of Arc100
---------------------------
* Complete custom character set (8 by 10 pixels) 'turbo-poked' onto the screen
* Intelligent buffering - does not display characters until there is a break
in the transmission or a cursor movement occurs
* On-screen clock showing current time or elapsed connect time
* 132-column mode (SET TERM/WIDTH=132 in VAX/VMS performs a spectacular mode
change - most other VT100 emulators simply clear the screen)
* Four speeds of scrolling (1,2,5 or 10 pixels at a time)
* Double-height/double-width characters
* Knows all the 'funnies' used by full-screen editors such as VAX/VMS's EDT
* Custom variable-width cursor
* Point-and-click with the mouse to move the cursor
* Individual tab setting allowed
* Custom dialogue box system - auto-scales in 132-column mode
* Exit to the Desktop and re-entry into the emulator by clicking on its icon
again returns to it in exactly the same state as it was left
How to Use Arc100
-----------------
The application installs an icon bar icon when double-clicked. This simply
has the standard Info and Quit options and needs no further explanation.
Clicking on the icon bar icon with the left or right buttons will enter the
emulator (or re-enter where you left it). Arc100 takes over the whole screen
in MODE 12 (or MODE 16 for 132-column mode) and hence I did not bother
making the code multi-tasking. The other reason is because high-speed on-screen
poking is performed for most operations - this is infeasible with windowed
multi-tasking programs.
The status line at the bottom of the screen ("Line 25") displays the following:
* Four LEDs simulating VT100 LEDs 1 to 4. Clicking on them will toggle their
status, as will sending the appropriate escape sequence.
* VT100/VT52 mode indicator. Clicking on this will toggle between VT100 and
VT52 emulation.
* Online/Local indicator. Again, click to toggle. "Online" mode means that the
host must generate characters to be displayed, whereas "Local" means that
you may type locally and the characters are displayed and not sent to the
host (and any characters generated by the host are ignored). "Local" mode
is very useful for testing certain escape sequences (try ESC # 8).
* Cursor X,Y position. Can be handy in some circumstances (especially dreaded
IBM mainframes !).
* Setup. Clicking on this will bring up a very self-explanatory dialogue box
(Setup 1) with options in it to jump to further boxes (Setup 2 and Setup 3).
* Reset. Clicking on this will reset the terminal to the settings immediately
after the last save or load of the setup file. Unlike some other terminal
emulators, this does NOT involve a re-load of the settings from disk.
* Exit. Clicking on this will return you to the Desktop, BUT you can return
to exactly the same position (including intact screen text) by simply
clicking on the icon bar icon again.
* Program version string. Click on this for a version dialogue box containing
RS423 transmit/receive figures too. This facility is omitted (due to lack
of space) in the 132 column mode.
* Clock. Can display nothing at all, the current time or the elapsed connect
time (the later can be reset by simply clicking on the timer).
Saving the Setup
----------------
There is an option in the Setup 1 dialogue box to load the setup and also an
option in Setup 2 to save it. Please note that the setup will NOT be loaded
when Arc100 is first run and installed on the icon bar. It only loads when
the icon bar icon is clicked on for the very first time, so floppy users
should not remove the disk with Arc100 on until the icon bar icon has been
clicked on to enter the emulator. You may add a saved setup filename to the
end of the execution line in the !Run (the default is <Arc100$Dir>.!TermSetup),
but Arc100 does not have its own filetype for these setup files. You may
execute the !RunImage binary with a -help qualifier to get a page of slightly
useful information.
Other Special Bits
------------------
The numeric keypad acts identically to a VT100 keypad. Num Lock / * and #
behave as PF1 to PF4 (as do, incidentally, the function keys f1 to f4).
Break on its own sends a short break, whereas Alt-Break sends a long one.
Home locally homes the cursor and Shift-Home locally clears the screen as
well as homing the cursor.
IntelliMouse System
-------------------
This is an intuitive method of moving the cursor (in Online or Local mode)
using the cursor keys or the mouse. If the mouse is clicked on a character
cell, then the cursor will move to that position (or directly in Local mode).
It does this by sending up/down sequences to the host first (and abandoning
this if the cursor never reaches that line - some editors have a scrolling area
which defeats this) and then left/right sequences afterwards. The cursor keys
also have their intuitive meanings: Shift-Left or Shift-Right skip to the end
of the word and Ctrl-Left or Ctrl-Right go to the appropriate edge of the line.
Technical Section
-----------------
Arc100 is written ENTIRELY in ARM code and has been 'file-protected' to avoid
tampering. The source code exceeds 250K and has not been supplied with this
PD release. I used a Plessey PT100 (plus the manual) to test out my theories
to the limit - the PD 'vttest' C program was also quite a help.
No, I'm not stupid enough to use a second screen buffer to save the screen
between invocations - the character plotting routines are quick enough to
allow redraw from a character grid in memory. The whole application needs only
a 48K WimpSlot (plus 136K screen space of course for MODEs 12 and 16).
Known Problems with Arc100 Beta-Test 2.2
----------------------------------------
* When the cursor is over a bold character, the character should be visible
in some form of reverse video, but the palette messes this up and the
character becomes almost invisible...
* XON-XOFF code rehash has not been fully tested yet - may be suspect under
extreme circumstances.
Missing Features of Arc100 Beta-Test 2.2
----------------------------------------
* New RISC OS baud rates (e.g. 110 baud). Should really allow receive and
transmit rates to be set separately.
* File transfer protocols. Should permit ASCII transfer at the very least.
* Printer support. I'm sceptical about this because most people would probably
prefer to transfer the files up (and print them on the host) or down (and
print them on the Archimedes). Besides, have you ever seen a printer that
does a full VT100 emulation ? :-) Better would be a simple session logging
facility.
* Tektronix graphics. Also sceptical here, but if enough people demand it, then
I might consider it.
* Multi-tasking support. Fat chance of this considering the design of
the program. There's no way I'm sacrificing the speed of the emulator :-)
* OSCLI support. An easy one to add, but one open to abuse (e.g. running
new applications or, even worse, memory editors).
Revision History
----------------
Beta-Test Releases
------------------
Version 2.2 (January 1991)
First PD release, but not 100% perfect yet. I've been at the code for
over 2 years now (on-and-off of course) and it's about my biggest
project ever. XON-XOFF still unstable. Plenty of code tweaks everywhere.
Fixed function key problem (wasn't restoring properly on exit to Desktop)
and also made the Desktop exit/re-entry smoother (only changes MODE if
it has to).
Version 2.1 (December 1989)
Worked prior to RISC OS, but RISC OS's XON-XOFF support doesn't like long
event routines (mine flashed a cursor), so this version dropped more
characters than an episode of Dallas :-) Added RISC OS support in the form
of an Info Window and menu, plus the ability to exit and re-enter the
emulator exactly as you left it.
Version 2.0 (mid-1989)
Added an incredibly fast section to the character output routine. If a
completely plain character is plotted, then pre-expanded characters are
blitted straight onto the screen - providing a 4-fold increase in speed !
Version 1.0 (mid-1988)
Sick to death with the lack of a DECENT VT100 terminal emulator for use
with VAX/VMS, so slaved for a solid month to get an Arthur 1.20 version
of Arc100 working. Just a straightforward Absolute application with pretty
characters (understatement of the year there !).
Where to report bugs or suggest enhancements
--------------------------------------------
Sorry to hog the source code to myself, but it's been my baby for a long, long
time and I'm not ready to put it up for adoption (or should that be adaption ?)
yet :-) Maybe sometime in the future when it stabilises (1995 ?).
Post Office Mail: Richard K. Lloyd, JANET e-mail: rkl@uk.ac.liv.cs.and
1, Banks Road,
Lower Heswall,
Wirral,
Merseyside.
L60 9JS