Toshiba T1100 — why a laptop without a hard drive was named an IEEE milestone of electronic engineering?

A laptop, which was intended “for mobile professionals”, with up to 8 hours of battery life, with an $1899 price… in 1985. How was it possible? This is a hero of this story, Toshiba T1100 Plus:

Let’s check how it works.

Specs

In the 80s, computers already were an important part of everyday life, and it was obviously nice to have a portable computer that you can take with you, with all the files, documents and personal data. Well, at that time mobile computers were not ‘portable’ but ‘luggable’, and the reason was obvious, the first portable computer, the Osborne I, was looking something like this:

This machine, released in 1981, was, by the way, the first commercially successful mobile computer, but of course, in reality, with a 24.5 lb (11.1 kg) weight it was far from portable. But the progress was going further, and already in 1985 Toshiba engineers made the laptop, which could be easily placed in the bag. How did they do that? Several components were crucial for this:

• Display. Heavy and bulky CRT was replaced by a thin and light LCD. These displays had a slow refresh rate and low contrast, but for working with documents it was good enough.
• Screen backlight. Which backlight? Toshiba T1100’s LCD had no backlight at all — the user had to care for enough ambient light. This solution may sound weird nowadays, but in the 80s and 90s, it was pretty common for wristwatches, Psion or Palm PDAs. And even today lots of people enjoy reading books from eInk screens, so the passive screen is actually not a too bad idea.
• Hard disk drive. What kind of disk drive? There was no disk drive at all in Toshiba T1100. This solution may sound weird nowadays (did I already write it?) but at the MS-DOS time, it was common to have a PC with one or two floppy drives. Hard disk drives were bulky and expensive, and the software size was also small enough to run from a floppy drive. My Windows folder size is about 20 GB nowadays, but the MS-DOS minimum install was only about 65 KB — no problem to put the system files and needed software on the same floppy diskette and run it.

With all these changes, Toshiba managed to build a computer, which not only had good enough specs for that time but was also portable and more or less affordable.

And it was a really successful product — the T1100 became not only “the world’s first mass-market laptop computer”, but it was even cloned in the USSR under the name Electronika MS 1504. In fact, it was the only laptop in history, which was produced in the Soviet Union. Toshiba T1100 is also placed in London’s Victoria and Albert Museum of art and design, and this computer actually deserves it.

As for the laptop’s hardware, it may look not fascinating today, but for 1985, the T1100 was good enough: 4.7 MHz 8086 CPU (7.16 MHz for T1100 Plus), 256 KB RAM (640 KB for T1100 Plus), 640x200 LCD display, optional 1200bps modem and two 720 KB 3.5" floppy drives. T1100 had a relatively small weight and stunning 6–8 hours possibility of autonomous work — even nowadays not every laptop can do this. This is especially impressive because the laptop has a NiCd battery, lithium batteries were not yet widespread.

Hardware

Let’s see what is inside.

As we can see, Toshiba T1100 has a nice keyboard, which was traditional for laptops of this era — the laptop itself is thick enough, so the ±0.5cm thickness difference for the keyboard did not really make sense, the trend of using ultra-slim keyboards was not “invented” yet. At the top, we can see a 4000 mAh 4.8V NiCd battery. It is interesting that there are not so many components on the motherboard — the laptop was made as cheap and compact as possible, there is no hard disk drive, no slots for external cards. The motherboard has only two floppy drive slots and a memory extension slot:

The memory extension card is proprietary, in the 80s SIMM or DIMM modules were not in wide use yet. The RAM module has a size of 384 KB:

Both floppy connectors are 26 pins, they have both data and power lines in one flat cable. This standard is not compatible with “standard” IBM PC 34-pin floppy drives, but the special adapter from 34 to 26 pins can be used:

I bought this one on Aliexpress, but it looks that these adapters are not in stock anymore, probably the marketing demand is really low. A similar adapter can also be made from two flat cables using this connection scheme:

Floppy drive 34 pins connector   => 26 pins connector

2  | REDWC | Density Select      => 6
4  |  n/c  | Reserved            => 9
6  |  n/c  | Reserved            => n/c
8  | INDEX | Index               => 2
10 | MOTEA | Motor Enable A      => n/c
12 | DRVSB | Drive Sel B         => 4
14 | DRVSA | Drive Sel A         => n/c
16 | MOTEB | Motor Enable B      => 10
18 |  DIR  | Direction           => 12
20 | STEP  | Step                => 14
22 | WDATE | Write Data          => 16
24 | WGATE | Floppy Write Enable => 18
26 | TRK00 | Track 0             => 20
28 |  WPT  | Write Protect       => 22
30 | RDATA | Read Data           => 24
32 | SIDE1 | Head Select         => 26
34 |DSKCHG | Disk Change/Ready   => 8
+5V                              => 1,3 or 5
GND                              => 15,17,19,21,23 or 25

Using the floppy diskettes can be tricky nowadays, but this 34 pins connector allows to use of the floppy drive emulator, which makes loading different applications much easier:

Several 720KB diskette image files can be saved directly on the USB flash drive (to enable support of 720 KB drives, a FlashFloppy firmware should be installed first), buttons can be used to switch between images.

The backside of the laptop is more or less standard for that time:

On the left side, we can see COM and LPT ports. On the right, we can see the CGA RGB port (which is not compatible with a modern VGA) and a composite video port. Yes, this laptop could be connected directly to a TV, which allowed showing the image on a big screen using a whooping analogue TV resolution. HD and 4K projectors were not invented yet, so a large CRT screen may be a good way to make a public presentation in the 80s. I don’t have a TV from that time, but the composite output works on a modern TV as well, if this TV has a composite input of course:

The image is definitely brighter and bigger compared to the internal laptop’s LCD. Switching between the LCD and external screen can be done by pressing Ctrl + Alt + End.

Software

The original OS for this laptop is Toshiba’s OEM DOS 3.20, the boot disk image can be easily found online. The easiest way to prepare floppy images with different applications is to use a DOSBox emulator and two similar 720KB diskette image files. I did a copy of the original DOS image, mounted both images to a DOSBox and removed all unwanted files from the second image:

These 5 files on the disk “B” are needed for the normal OS boot, others can be easily removed, after that, there is about 650 KB of free space on the diskette.

It is a sort of challenge to find software that can run from a 720KB disk, but surprisingly, it is actually possible. The Word Perfect editor was pretty popular in the MS-DOS time, and version 4.1 can easily work from a floppy — it requires only about 250 kilobytes of space:

Of course, editing features are pretty basic, but the Word Perfect is good enough to work with text documents, and it is anyway better than an “old-style” mechanical typewriter. Surprisingly, WordPerfect for Windows still exists even today, but it obviously cannot run from a single 720K floppy anymore — even version 5.1 for DOS had about 3MB size.

The next fascinating application is the WordStar 3.30 — it’s a pretty simple text editor, and its size is less than 100KB.

It will be a challenge even for modern developers to do something like this, highly likely that this editor was written using the 8086 Assembler language — the “art” which is almost forgotten today. The WordStar has a very long history, the first versions were working even on CP/M OS, before the DOS era.

The next application, PC Globe, could be pretty useful at a time when there was no Wikipedia and no Google Maps:

This application has a 1.3 MBytes size and can work from two 720 KB diskettes, its size is almost the maximum which the computer without a hard disk drive can do.

The laptop has a serial port and an internal modem, it is also interesting to test the connectivity features. MS-DOS Kermit (app size is 257 KB) is a communications software package, it allows to connect via modem to another computer or to the external BBS (Bulletin Board System):

Using the dial-up connection with the BBS or remote office computer, it was possible to get mail, upload or download files — yes, it was doable even in the “pre-Internet” era. It can be tricky to test the dial-up connection — most households do not have telephone lines anymore, but the modem can be emulated using the Raspberry Pi or ESP8266 board. And surprisingly, some BBSs are still supported by enthusiasts, more detailed description I wrote in another article.

From the programming perspective, BASIC was a sort of standard for home computers in the 80s. QBASIC can easily run from a floppy disk. I was using the same code for testing another model, Toshiba T3100, and it works on the Toshiba T1100 as well.

Alas, I did not succeed in running a C/C++ compiler — the Turbo C++ installer requires 4 floppy disks, there is no chance to run it without a hard disk drive.

As for the gaming experience, it was surprisingly not too bad as I expected. The Digger game is one of the iconic games of the DOS era, and its executable has only 57 KB in size:

One of the oldest games, I tried, the Pac-Man, was released in 1983, the game size is only 33 KB:

The Arcanoid is also one of the hits which became classical, and the game size is only 226 KB:

The Prince of Persia looks surprisingly good, considering that the game size is only 500 KB:

The Blockout is a sort of 3D-Tetris game, its size is only 210 KB:

And finally, the Battle Chess game, which I already tested on another DOS machine, has a 600 KB size, it can also run from a 720KB floppy drive:

Of course, this machine was not intended for gaming, the LCD screen brightness and refresh rate are not so great, but spending some time playing games was quite possible.

Conclusion

It was interesting to test the Toshiba T1100, and as we can see, it was pretty nice for its time. Running software on a computer without a hard disk drive looks almost impossible nowadays, but the software in 1986 was not so big in size, and most of the programs can run well using the 720 KB diskettes. Compared to other models of that time, the Toshiba T1100 was really lightweight and portable, and I can easily imagine that for travellers, journalists, scientists and other people who had to work “in the field”, it was a real step forward. Last but not least was the price — the Toshiba T1100 was really ahead of its time, even 10–20 years later the average laptop price was much more than a 1899$.

Of course, this situation did not last too long — the software size was increasing, and the computer with such specs had no chance to be competitive for a long time. The next model, Toshiba T1200, had a 20 MBytes hard drive, and I will test it next time — stay tuned.

Those who are interesting in more details about vintage computers testing and restoration are welcome to read other articles:

• Toshiba T3100 (1986)
• Toshiba T3200 (1989)
• Compaq LTE 5150 (1996)