Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!seismo!gatech!amdcad!bandy From: bandy@amdcad.AMD.COM (Andy Beals) Newsgroups: comp.sources.d,comp.terminals,comp.emacs Subject: Re: VT100's keeping up at high baud rates Message-ID: <17160@amdcad.AMD.COM> Date: Tue, 16-Jun-87 14:58:28 EDT Article-I.D.: amdcad.17160 Posted: Tue Jun 16 14:58:28 1987 Date-Received: Sun, 21-Jun-87 07:28:47 EDT References: <1149@carthage.swatsun.UUCP> <8601@tekecs.TEK.COM> Reply-To: bandy@amdcad.UUCP (Andy Beals) Organization: Advanced Micro Devices, Inc., Sunnyvale, Ca. Lines: 54 Summary: Modern-day terminals are severely lacking Xref: mnetor comp.sources.d:853 comp.terminals:313 comp.emacs:1166 A number of people have written how a number of terminals and terminal emulator programs on micro-toys cannot keep up with a decent baud-rate. In article <4101@teddy.UUCP> jpn@teddy.UUCP (John P. Nelson) writes: >I once did some benchmarking that you all might find interesting. I >wrote a program which did nothing but fill a 80x24 screen with blanks >several times, [...] The only >escape sequences I used were 'ESC [ H' to home the cursor after >reaching the bottom, and the inverse video character attribute on/off [every other pass] >Flow control was enabled to avoid overruns. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Thus invalidating the test. I don't WANT the terminal to send flow-control. In this day and age, where 64k x 8 of ram chips is cheap, TERMINALS SHOULD NOT HAVE TO SEND FLOW CONTROL BACK UP THE WIRE. TERMINALS SHOULD HAVE LARGE BUFFERS SO THEY MAY BE OF REAL USE IN DAY-TO-DAY OPERATIONS. The stupidest trend I've seen is the inclusion of microprocessors in terminals. Well, perhaps not, but the people who *program* the micros are patently PINHEADS. The VT52 was a *wonderful* terminal. Then came the VT100. It could not display characters as quickly. Now we have the VT220, which is even slower than the VT100! Every time DEC (or someone wanting to be DEC-compatible) comes out with a new terminal, it can not accept continuous data at as high of a rate as its predecessor. >Anyway, true VT100's had a throughput just over 9600 baud. VT101's had >a throughput of only 4800!!!! VT220's could go a sustained 19200 baud! Your benchmark was invalid due to the fact that you enabled flow control. If a terminal can't continuously display a couple of screens worth of text while taking input without resorting to brain-damaged flow control then it is no good. I would be interested in seeing a benchmark like the one that JPN did, but one that records and reports "Terminal wimped out and tried to use flow control %d times." Perhaps one could be done using termcap and that way we all can test the buggers. -- 55 is failing 70 is passing Andrew Scott Beals, {lll-crg,decwrl,allegra}!amdcad!bandy +1 408 749 3683