Data General Portable PC

DataGen002

By Corey Sandler

Is the Data General/One the crowning achievement of the IBM-compatible laptop portable race? Or, is it yet another triumph of nascent technology over real-world utility?

Well, it all depends on how you see it.

The DG/One is an MS-DOS compatible, full-keyboard, battery-powered microcomputer that can be equipped with a pair of built-in disk drives and 300 baud internal modem. It is possessed of the first commercially applied full-screen (80 characters by 25 lines) liquid crystal display (LCD). And, though at 11 or so pounds for the standard configuration it is not quite the weight or size of a three-ring binder, it does honestly qualify for the title of “portable.”

Prices start at a hefty $2895 for a 128K, one disk drive machine. A second internal disk drive lists for $599, and each block of additional 128K of RAM is listed at $599. The internal modem lists for $250, an external 5.25″ disk drive for $795, and a portable thermal printer for $499. A battery pack and recharger and a carrying case for the whole system each list for $99.

Under the hood beats an 80C88 microprocessor heart, the low-power CMOS equivalent of the 8088 chip used in the IBM PC and compatible machines. The DG/One comes equipped with at least 128K of RAM, expandable in blocks of 128K to as much as 512K. However, the video display circuitry of the machine does not have its own memory, and therefore you must lop off the first 48K of RAM for the screen. If the program you intend to use requires 256K of RAM, you will actually have to move up a notch to a 384K machine.

And, unlike many other laptop portables, the RAM is not kept under power when the computer is shut off; like a standard microcomputer, the RAM is volatile and information in it disappears when the power is shut off or the batteries run down. You must be certain that the contents of RAM are copied to permanent storage on disk.

The computer has several disk storage options, beginning with one or two built-in 3.5” disk drives. These drives, based on the Sony technology also used by Apple in its Macintosh machine, can store as much as 720K of data each – twice the capacity of the IBM PC floppy disk drives and two-thirds of the way to the high-density storage of IBM’s 1.2 megabyte drives in the PC-AT machine. The disks are formatted at 512 bytes per sector, with eight or nine sectors per track, and 40 or 80 tracks per side, yielding the 720K top end.

Safe and Sound Disks

The disks themselves are nicely protected inside plastic carriers, with a sliding metal door protecting the medium from fingerprints, dirt, and paper clips. However, because the size and design of the drives are different from the 5.25” floppy system found on the IBM PC, using a program written for the IBM requires a few extra steps – you must either buy special 3.5” disk versions of software or download programs from a 5.25” drive or a telecommunications source. Data General sells an external 5.25” drive with connector to the DG/One to allow direct exchange of magnetic media with an IBM PC or compatible.

Be aware, though, that you will not be able to transfer copy-protected software to the smaller disk format, and that the software use license for a particular program may legally limit use of a program to a single computer. The seller may object to a user making copies for use on a PC at the office and a DG/One for the road.

Another issue involves software that is tied directly to hardware rather than to the MS-DOS operating system. Data General appears to have done a good job of ensuring near-total compatibility through careful design of its BIOS system which is present as part of its adapted MS-DOS system. Data General provided downloaded 3.5” disk versions of standard WordStar and ThinkTank for this review. The system also booted up IBM DOS 1.1 on one disk I tried.

Data General has announced that it will make available soon an expansion unit for the portable that will include five IBM-compatible hardware slots and hold an external 5.25” floppy disk drive or another storage option. The box – the size of a small desktop computer – will allow use of an IBM or compatible display card and other devices. The price had not been set at the time this article was prepared.

The MS-DOS package from Data General includes Microsoft’s GW-Basic, which is a functional equivalent of IBM’s BasicA. (Here is a free inside tip: If an applications program on any PC-compatible absolutely insists on finding a program called BASICA.COM before it will execute, you may be able to save the day by renaming GW-Basic as BasicA.)

The LCD: Good News and Bad News

It is the LCD display that is both the boon and the bane of the machine. By opting for the full-sized screen, Data General (and its Japanese manufacturing and design arm Nippon Data General) has dealt nicely with one of the most damning criticisms aimed by many at the rest of the crop of laptop computers.

Pioneering devices like Radio Shack’s Model 100 display only 8 lines of 40 characters. Other newer machines like Epson’s PX-8 have pushed the frontier to 8 lines of 80, while Hewlett Packard’s Portable goes one step beyond to 16 by 80. And in November, Texas Instruments announced its entrance into the fray with a device called the Pro-Lite, which includes an LCD with the same display abilities as those of the Data General/One.

Data General’s machine mimics the full IBM PC display. It will show a full page of text from a word processor, or it can show a full-sized Lotus 1-2-3 screen. And, if you are so inclined, you could check up on the pilot by running the standard (monochrome) screen of Flight Simulator on your lap as your jet lines up on final approach to O’Hare.

The inherent nature of the LCD screen is that it works with the aid of reflected light rather than as a light source itself like a cathode ray tube (CRT) or other luminescent technologies (see “Hi-Res and Color Liquid Crystal Displays” in this issue). And, it seems that the larger the screen and the smaller the pixels (and therefore the more information displayed) the more difficult it is to find just the right amount and angle of light for viewing.

The reason the LCD screen has been adopted by nearly every manufacturer of battery-powered portable computers is that it draws very little current, thereby allowing the use of relatively small and lightweight batteries. Other technologies, such as electroluminescent screens, plasma displays, and low-power CRTs for battery-operated machines, are still in the labs.

Impressed though I was by the technological achievement of the full screen, I found it a bit of a strain to read in most situations. The best lighting I found was from a strong but indirect source over my shoulder- I’m not certain that an airliner’s overhead spotlight would save me from a headache. The contrast of the DG screen can be adjusted through commands from the keyboard, but the angle of the screen cannot be changed – it is either open or shut. And, the characters on the review model I used did not seem as sharp as those displayed by the smaller and more limited Radio Shack and Epson machines I have used.

The Vital Statistics

DataGen001

The device itself is also larger than the “typical” laptop computer, measuring 13.7″ by 11.7″ by 2.8″. Its starting weight is 9 pounds, with a single disk drive and without the optional rechargeable battery pack. With a second drive and batteries, the system crosses the 11-pound threshold. I was quite surprised to discover that the unit did not include a built-in carrying handle; a separate case or briefcase is necessary.

The batteries are supposed to be good for at least eight hours of typical use – disk drive and modem operation consume more power than do screen display and computation. Recharging the batteries requires use of a small transformer cube and power cord; operating the computer directly from an AC outlet requires a different transformer cube and power cord.

The microprocessor runs at a clock speed of 4MHz, almost 20% slower than the IBM standard of 4.77MHz. The difference was noticeable in computation intensive operations like screen updates. Data General included with my review package a copy of a PacMan-like game, and fighting boredom I was able to rack up record scores by outrunning the slightly slower ghosts.

Users familiar with the forgiving nature of the entrance slots of most 5.25″ disk drives will find the DG units to be slightly more demanding: the plastic case must be inserted exactly right or it will not drop into place for reading and writing operations. The disks include a small movable notch to write-protect contents – an improvement over the silver tape method used for floppies. By the way, the prices of the 3.5″ disks have settled thus far in a range of about twice the price of a 5.25″ floppy. Byte-for-byte, that makes the media identically priced.

The optional 5.25″ disk drive is called device C by the operating system, but the DG ROM BIOS has been told to boot from drive C if there are no disks in the first two internal drives. This should allow programs with their own operating systems to load from the external drive.

Making Your Own Disks

Copying from a 5.25″ disk to a 3.5″ disk is a straightforward procedure using the copy or diskcopy command. (Using diskcopy, though, will format the smaller but more capacious disk as a standard 320K or 360K disk, depending upon the formatting of the original.)

Going the other way, from the small internal disks to the external floppy requires the copy command, and you must consider the halved capacity of the floppy – it could take two floppies to store all of the data recorded on a single 3.5″ disk.

One other storage option for DG users is a RAM disk (also called an “electronic disk” or a “virtual disk”). This is a program that fools the operating system into thinking of a portion of RAM as a disk. Programs and data can be copied into and out of the RAM disk at a significant increase in speed over the physically limited real disk drive. You must take care to observe two cautions, though: first, any data in the electronic disk must be stored to a permanent disk before power is shut off, and second, you must leave sufficient RAM available for the needs of an application program. For example, WordStar requires at least 128K. Together with 48K for the screen display memory, the first 176K must be left untouched in such an application. DG’s supplied VDISK.COM program creates a CONFIG.SYS add-on to DOS, calling the RAM disk drive D.

The DG/One keyboard is a competent device, about half an inch narrower than a standard typewriter or computer board. The 79 keys have a sure, dicky feel to them, slightly softer than the IBM PC model but should prove quite comfortable for most users. Across the top of the board are ten downsized function keys, plus Ins, Del, Num, Lock, Scroll Lock, and PrtSc buttons. A carrier just above the function row holds a plastic cheat sheet card that can be used to remember specialized assignments given the keys.

In addition to the standard Shift, Ctrl, and Alt keys, DG has added a Cmd key, a Spcl key, and a blank and thus far unassigned key along the right side of the board. A set of four cursor control keys resides along the bottom right – the horizontal placement of up, left, right and down are not my favorite arrangement. The small board understandably does not include a separate cursor key pad. Instead the UIO/JKL/M keys can be toggled into roles as the bottom half of a keypad for number entry.

A Choice of Video Options

The DG/One equivalent of a video display adapter can be set to emulate the IBM special monochrome adapter and screen or the IBM Color/Graphics adapter. Commands from the DOS prompt can also set the display to 40 characters. At the Comdex show last November, I saw the DG/One with a prototype of the expansion box with a standard IBM Color/Graphics board driving an RGB monitor.

One of the more common uses for a portable computer is as a link to a main office computer for electronic mail, database inquiry, or transfer of files. Other users tie into public networks like MCI, the Source, and CompuServe for various purposes. The DG/One accommodates these uses through an optional 300 baud direct connect modem, or through an RS-232C serial port that can be wired to an external modem. Data General will offer a 1200 baud device, but the price had not been set at the time of this review.

The DG internal modem follows Hayes protocols, including auto-answer. The device comes with a T-connector allowing a telephone to be plugged into the same line to allow you to switch back and forth between voice and data communications. Also available is a set of acoustic cups to be used with nonmodular telephones.

I tried the modem with MCI mail and had no trouble using that system’s commands. I did not have a full-function telecommunications program to test uploading and downloading. One word of warning: the communications chip set used in the CMOS system of the Data General is not the same as that used by the IBM PC and most compatibles, and as such it is a good bet that many off-the-shelf communications programs will not work on the machine. You’ll probably have to use an altered version.

I also successfully linked the DG/One directly to my IBM PC using a null modem cable, the system I use to download data from my personal portable. The two computers, both under control of my IBM, swapped files at a gratifying 9600 baud.

The Built-In Programs

The DG/One includes four small scale utility programs on a ROM chip inside the unit, including a terminal program that allows configuration of the portable as a standard terminal or as an emulation of a Data General Dasher terminal. Options include use of an internal or external modem, output flow control, and several other protocol elements – but no way I could discover to save files to disk or retrieve from disk or RAM.

Another of the ROM programs is Notebook, a simple text processor that can be used in conjunction with the modem for sending and receiving files, or as a quick memo pad. The program will hold as many as 500 lines of 80-column text in RAM. The other two options are a Setup configuration program (the settings are retained in a small portion of RAM that is powered by a separate lithium battery that also runs an internal clock/calendar) and a set of extended diagnostic routines to check memory chip-by-chip and test the various available disk drives.

There is also a built-in self-diagnosis program that is invoked when the computer is first turned on. The test reports net available memory (48K of RAM is taken by the operating system) and then a numeric code indicating any tests failed by the computer. The routines check the microprocessor, RAM, ROM, DMA controller, LCD controller, keyboard and speaker interfaces, various interrupts, power supply, output ports, and the internal memory if installed.

DG also sells a portable 27-pin thermal matrix printer that connects to its own serial output port on the computer. Powered either by its own set of rechargeable batteries or from an AC outlet, the device can work with regular bond paper using a special thermal transfer ribbon, or with specially coated thermal paper. According to Data General, the printer emulates an Epson MX-80 with Graftrax or its close cousin the IBM PC Graphics Printer, running at 40cps for draft quality and 20cps for “letter-quality” printing.

What’s New?

The DG/One pushes LCD technology to its present commercial frontier. In addition to obtaining sufficient supplies of the new large screens (Epson is reported to be one of the OEMs), engineers also found a way to deal with the “ghosting” problem often associated with LCDs. In effect, the large DG/One screen is treated by the computer as if it were several smaller screens with an individual driver for each portion of the display.

Another interesting design choice was the use of 8K by 8-bit RAM chips instead of the more common 64K. by 1-bit chips. Both devices will store a total of 64K bits, and therefore in a bank of eight will store 64K bytes. However, the IBM PC design stores each bit of an 8-bit byte in a separate chip, while the DG stores all eight bits in a single chip, saving another smidgen of power.

The construction of the machine seems solid, although the plastic shell does have the appearance of a device selling for less than $3000. A hinged cover at the back of the unit slides into place to cover the panel of connectors at the back and also serves as a prop to adjust the angle of the machine; it popped out of its grooved track every time I used it. DG does not endorse users taking the covers off to install add-ons. If the machine does make a significant dent in the marketplace, though, third-party manufacturers may seek to tie into the planned expansion chassis or attach to one of the ports.

Who should consider buying a device like the DG/One? Well, I spoke recently with a book editor who said his company’s sales staff was lugging one of those 40-pound “transportable” PC-compatible machines around the country for use in order entry and communication with the home office – the DG/One would be a quite worthy, back-saving replacement. It would also make a worthy companion for traveling heavy users of electronic spreadsheets.

You should have noticed by now that the only significant knock against this machine – assuming you can afford the price of admission – is based on a completely subjective decision about the LCD screen. A long word processing session did not appeal to my tired eyes. But, if you are considering the purchase of a portable, go and see for yourself.

Data General’s achievement with its portable computer is in a way comparable to IBM’s with its original PC model. The technology – with the exception of the LCD screen – is proven, off-the-shelf provisioning. What DG has done is make up a package combining a very high degree of PC compatibility, several disk storage options, a capable keyboard, and perhaps most important, added into the mix an established and respected name. You might say that the company immortalized in “The Soul of a New Machine” has brought a little of that soul from the minicomputer to your lap.

Hardware Profile

  • Name: Data General/One
  • Type: Portable PC-compatible computer
  • CPU: 80C88 at 4Mhz
  • RAM: 128K standard, can be increased to 512K in blocks of 128K
  • ROM: 32K
  • Operating system: MS-DOS 2.11. Can also use CP/M-86
  • Keyboard: 79 keys, with 10 function keys
  • Display resolution: LCD display of 640 by 200 pixels, or 25 lines of 80 characters.
  • Ports: Two serial ports built in. Expansion chassis that will accept IBM compatible hardware cards announced.
  • Dimensions/wt: 13.7” x 11.7” x 2.8”. Approximately 11Ibs. With two disk drives:
  • Documentation: Instruction manual
  • Summary: The first commercially available full-screen LCD portable computer with a high degree of PC compatibility.
  • Price: $2895 for unit with 128K RAM, one internal disk drive.
  • Manufacturer: Data General, 4400 Computer Dr. Westboro, MA 01580

First published in Creative Computing, February 1985

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