[comp.sys.apple2] VT100- why?

bazyar@ernie (Jawaid Bazyar) (01/13/91)

In article <10975@darkstar.ucsc.edu> unknown@ucscb.UCSC.EDU (The Unknown User) writes:
>	Nobody answered my question why VT100 was so damn important either...
>just curious..

   Because VT100 is an industry standard.  Xterms are based on VT100.
Everyone uses VT100.  It's robust (except for my implementation, at the
moment :-) does everything under the sun, and is indispensable for Unix
work.
   Please, don't reply extolling the virtues of Proterm Special.  Proterm
Special is a duplicate of the Apple II monitor display features with sound
and maybe four extra commands added.  It's really weak.  Some people 
with 2400 baud complain that VT100 is 'slow'.  I disagree. I insist that
THEY are the ones that are slow.  Perhaps 5% of the text sent is vt100
commands in a typical VI session.


--
Jawaid Bazyar               | Being is Mathematics 
Senior/Computer Engineering | Love is Chemistry
bazyar@cs.uiuc.edu          | Sex is Physics
   Apple II Forever!        | Babies are engineering

gwyn@smoke.brl.mil (Doug Gwyn) (01/13/91)

In article <1991Jan12.215222.13905@ux1.cso.uiuc.edu> bazyar@cs.uiuc.edu writes:
>   Because VT100 is an industry standard.  Xterms are based on VT100.

Xterm interprets a subset of X3.64, and not the same subset as a VT100.
VT100s offer pretty much a minimal subset of X3.64, so that if you
pretend you have a VT100 when using some other X3.64 implementation,
odds are that most applications would be usable in that mode.

>Everyone uses VT100.  It's robust (except for my implementation, at the
>moment :-) does everything under the sun, and is indispensable for Unix
>work.

There is nothing about UNIX that especially favors the VT100.

>...  Some people with 2400 baud complain that VT100 is 'slow'.

There is a noticeable slowdown in many cursor-addressing applications
when using X3.64 escape sequences rather than, say, VT52 sequences.
At higher bit rates, real VT100s and perhaps some VT100 emulations
have effective throughput considerably below the bit rate due to having
to stall host transmission while they catch up on processing previous
control sequences.  (This is only slightly worse for VT100s than for
VT52-like implementations, however.)

	- D A Gwyn
	  4.3BSD termcap editor

zane@ddsw1.MCS.COM (Sameer Parekh) (01/15/91)

In article <1991Jan12.215222.13905@ux1.cso.uiuc.edu> bazyar@cs.uiuc.edu writes:
>In article <10975@darkstar.ucsc.edu> unknown@ucscb.UCSC.EDU (The Unknown User) writes:
>>	Nobody answered my question why VT100 was so damn important either...
>>just curious..
>
>   Because VT100 is an industry standard.  Xterms are based on VT100.
>Everyone uses VT100.  It's robust (except for my implementation, at the
>moment :-) does everything under the sun, and is indispensable for Unix
>work.
>   Please, don't reply extolling the virtues of Proterm Special.  Proterm
>Special is a duplicate of the Apple II monitor display features with sound
>and maybe four extra commands added.  It's really weak.  Some people 
>with 2400 baud complain that VT100 is 'slow'.  I disagree. I insist that
>THEY are the ones that are slow.  Perhaps 5% of the text sent is vt100
>commands in a typical VI session.
	But vt100 is inefficient, to move the cursor to a spot, it is
ESC[ and then a number in ASCII so if it is two digits that it two bits
and a ; and another number in ASCII and some ending character. (I forgot
what.)
	If they used the ASCII VALUE for the numbers it would be much
more efficient.  (And I THINK the terminals would not need as much programming.)



-- 
zane@ddsw1.MCS.COM

bazyar@ernie (Jawaid Bazyar) (01/15/91)

In article <1991Jan15.023927.18026@ddsw1.MCS.COM> zane@ddsw1.MCS.COM (Sameer Parekh) writes:
>	But vt100 is inefficient, to move the cursor to a spot, it is
>ESC[ and then a number in ASCII so if it is two digits that it two bits
>and a ; and another number in ASCII and some ending character. (I forgot
>what.)

   Okay, so instead of 3 characters we have about 8 or 9 to move the cursor.
Curses on Unix was made to minimize cursor movement.  So this is really not
an issue.  BBSs with fancy MouseText pull down menus and such are so 
inefficiently written as to be laughable.  A TRUE Apple specific emulation
would encompass graphics, windows, menus, and the like.

>	If they used the ASCII VALUE for the numbers it would be much
>more efficient.  (And I THINK the terminals would not need as much programming.)
  Actually, interpreting the VT100 numeric codes takes less than 20 lines of
code in C.

>zane@ddsw1.MCS.COM

But for all you people still defending Proterm special, consider this.
VT100 was designed by many very intelligent, knowledgeable people over
the course of a decade.  PTSpecial was "invented" by a high school student.
Take your pick- I choose VT100 because it is orders of magnatude more robust.
Vt100 looks at line noise, blinks, and goes on with it's life.  PTSpecial
goes apeshit (pardon my French) with line noise.  That alone is reason
enough to use Vt100.

--
Jawaid Bazyar               | Being is Mathematics 
Senior/Computer Engineering | Love is Chemistry
bazyar@cs.uiuc.edu          | Sex is Physics
   Apple II Forever!        | Babies are engineering