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Tony Lawrence: Qume Serial X-Terminal

Outdated material; included only for historical reference

There are people who swear they will never use a mouse on their computer. Such people object strongly to graphical interfaces, and will offer long and convoluted explanations of why character based interfaces are simpler, quicker, and just plain better.

Such die-hards are unlikely to be interested in X-Terminals. However, those with a more open mind will recognize that windowing environments do have advantages even if the windows are only used for character based applications. The ability to run applications literally side by side, to switch between programs while still keeping data visible on the screen, and the ability to cut and paste between programs are quite attractive to most users.

The Unix answer to the GUI (Graphical User Interface) question has been X-Windows. Unfortunately, X has required fairly expensive X-Terminals (specialized devices capable of running as X-Window servers) and the added complexity of Ethernet wiring. The prospect of replacing hundreds or even thousands of feet of existing RS-232 wiring has undoubtedly cooled many a system administrator's interest in X-Windows.

The Qume QX15 may be an answer. Priced at $699.00, the QX15 provides a standard serial terminal that also has the ability to run (monochrome) X-Windows. As a normal terminal, it is a plug in replacement for any Wyse 60, VT220 or PC Term terminal. No Ethernet cabling is used; it plugs directly into standard RS-232 wiring. It has the typical features that you would expect on a modern terminal: Two Serial & one Parallel ports, 101, 102 or ANSI keyboards, and so on. What is unexpected (if you weren't aware of the X capabilities) is a mouse port, and a mouse driven setup screen.

Setting up the QX15 as an ASCII terminal is very much like setting up any other terminal, except that you are using a mouse and pull-down menus. I was able to install it in place of an existing terminal in almost no time. The 83 page Setup Manual is complete and quite detailed, and includes a trouble-shooting section.

As a standard ASCII terminal, the QX15 holds no surprises. I used it quite extensively as such, and hardly noticed that it wasn't my "normal" terminal. The mouse driven setup interface is exceptionally easy to use. The keyboard seemed smooth and has the nice little extras such as raised bumps on touch-typist's Home Keys, and Number Lock, Caps Lock and Scroll Lock lights. The screen has a 78 HZ refresh rate, and the terminal meets Scandanavian emission standards.

The QX15 is not an X-Server. That is, it does not contain the capability within itself to allow X-Clients to run. The server software (X11R4) is supplied separately and must be installed on your host computer. As the software is available for DEC, Sun, RS6000 and Univel platforms in addition to SCO Unix, it must be obtained apart from the QX15 itself. This is purchased as a one-time site license, and is priced at $200.00.

Installation of the software is very simple, although Qume does not use SCO's {I}Custom{R} facility. If you have Open Desk Top, only one diskette needs to be read. This is because the Qume Server software can make use of the standard ODT window manager. If ODT-VIEW is not installed, another 9 diskettes must be loaded to provide a {I}twm{R} window manager.

Once the software is loaded, you log into the terminal just as you would on any ASCII terminal. This of course means that the terminal must be enabled, that the correct baud rate must be set, and that {I}/etc/ttytype{R} specifies the correct terminal type. Once logged in, a simple {I}startxgo{R} or {I}startxgo.odt will start an X session.

When running X, the terminal shows you a 800x600 window in an actual 1280x1280 monochrome display. Moving the mouse cursor to the edges of the display pans in the off screen portion. If you are running the ODT window manager, the panning feature and the monochrome display are really the only differences from running on the ODT console. If you do not have ODT, you would use the {I}twm{R} window manager.

The issue of speed naturally comes to mind when contemplating a serial device. Can X really run at an acceptable level of performance? As it turns out, it can, with only a little compromise in responsiveness.

When I first installed the QX15, it replaced an existing terminal that had been configured at 38.4K communications speed. The host computer was a Dell 486DX/33 with 8MB of ram, and initially it was connected to a Maxspeed SS8 board. The performance with this configuration was acceptable, certainly usable, but less than what you might wish for. Moving or resizing screens lagged behind mouse movement just enough to sometimes be confusing, and I found it a little troublesome to use pulldown menus. However, these complaints are really nit-picking, and only require a bare minimum of patience to live with. I would suspect that the average user would be quite willing to forgive this slight sluggishness in exchange for the obvious benefits of having X at their station.

I also wanted to see what the performance might be like over a modem. Supporting X applications remotely is an obvious application for this terminal. Therefore, I lowered the baud rate to 9600. At this speed, opening, resizing or even just moving a window can be somewhat difficult, because the screen often is considerably behind your mouse. The experience is much akin to using a text program over a 2400 baud modem. It takes a fairly forgiving nature to run at this speed, but if your choice was this or no X at all, you might feel that you could live with it.

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Obviously 38.4K is a much better choice for direct connections, and that speed is supported by most multiport serial boards. However, the QX15 is not limited to 38.4K. It is capable of running at a full 115.2K. In order to test at this baud rate, I installed a Digiboard PC/Xem communications board (this board was reviewed in SCO Magazine November 1992).

The Digiboard PC/Xem supports higher baud rates by way of a "fastbaud" option that lets you tell your system that you are running at 50 or 110 baud, but actually be at 57.6K or 115.2K. When operating as an ordinary terminal, these high baud rates seem to have no advantage whatsoever. Timings of cat'ing {I}/etc/termcap{R} are essentially identical from 19.2K on up. The problem is simply that the screen is unable to display characters as quickly as the serial port can receive them. This is not unusual; other terminals exhibit similar behavior. The Qume terminal does make use of the higher baud rates when running X, however. Wall clock timings of the startup time (draw all the icons and be ready for mouse input) decrease steadily as the baud rate is increased.

At 115.2K baud, the QX15 comes alive. Windows track the mouse without noticeable lag and switching windows is smooth and quick enough not to be annoying. Pull-down menus can still be a little difficult to navigate, but we humans have an amazing capacity to adjust: after an hour or so of use I found myself unconsciously adapting to the small delays in menu choices and really hardly noticed it as a problem. Someone accustomed to a true X-Terminal would undoubtedly require a longer period of adjustment, but an average character terminal user would find little to complain about.

The QX15 is a good choice if you want to ease into X-Windows without the expense and trouble of converting everything to Ethernet and true X-Terminals. The ability to run X at a cost comparable to high-end ASCII terminals opens up new possibilities for existing serially connected systems.

-----------------------

Reviewers Notes

Qume QX15

Qume Corporation 260 S. Milpitas Blvd. Milpitas, CA 95035-5420 (408) 942-4242

Description:

A serial ASCII/ANSI terminal that can run X-Windows applications.

Pricing: $699.00 Requires separate host Server software, $200.00 (site license)

Review Configuration: Dell 486DX/33 running SCO Open Desktop


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