[net.micro] VT100 emulation on personal computers

roberts@NBS-VMS.arpa (ROBERTS, JOHN) (07/31/86)

I recently purchased a communications program for my personal computer
(an Amiga) from a local computer store. (The program is called OnLine!,
and was claimed to be the best the store had to offer.) The main reason
for the purchase of the program was to use its advertised vt100 
emulation capability to communicate with host computers running Unix 4.2
and VMS, and to use the Rand, vi, and EDT editors. The emulator actually
seems to work pretty well (good 80x24 display, implementation of 
PF1-PF4, keypad usable for EDT keypad mode, reverse scrolling, etc.),
but has two idiosyncrasies I have observed thus far. One is a slight
deviation in the handling of line insertions and/or deletions that make
it difficult to use some of the features of vi and EDT. (There may be a
way to fix this, but I haven't found it yet.) The most annoying problem
thus far is an apparent inability to transmit the ASCII NULL character
(00 hex, usually implemented as ctrl-@ or ctrl-space). This is 
particularly troublesome because there are applications for which the
ability to transmit a NULL is very important. After several attempts to
find a way around this bug, and rereading the manual, I came to the
conclusion that this version of the program contained, as an added 
"feature", a filter to *INHIBIT* the transmission of a NULL character,
no matter how one tries to transmit it! Putting aside arguments as to 
the usefulness of the NULL character, the ability to transmit it is a
documented feature of the VT100 terminal, and I do not think that an
emulator program that deliberately suppresses this ability should still
be called a vt100 emulator.

Advice (or flame) to writers of commercial terminal emulator programs:
If you want to say that your program emulates terminal X, it should
in fact imitate its characteristics to the greatest extent possible.
If certain features prove impractical to implement (132 column mode on
a vt100 emulator, or reverse video, for instance), then these 
deficiencies should be clearly listed in such a manner that the customer
can find out about them before making the purchase. If you don't follow 
these practices, then you should advertise your program as "a sort of a
terminal emulator program that in many respects is remarkably similar
to terminal X".

Questions for Amiga users (since INFO-AMIGA is not currently running):

> Does the Amigaterm program have a vt100 emulator good enough for the
applications mentioned above? Will it transmit NULL characters? Does it
implement PF1-PF4?

> Is there a program called Maxicomm? Any experience with it?

> Any good public domain programs with vt100 emulators for the Amiga?

> Does anyone know of a fix for the emulator bugs in OnLine! ?

Thanks in advance for any help that can be provided. Corrections to my
obviously erroneous views welcomed.

"The human mind is an infinite resource, but only if you don't
squander it." - J. P. Hogan

                              John Roberts
                              ARPANET: roberts@nbs-vms.ARPA
                              USENET: I don't think direct contact is
                                      possible, so please post through
                                      net.micro.
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