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Schoenherr Braillotron TI-30

Date of introduction:  1978 Display technology:  LED-stick and Braille cells
New price:   Display size:  8 (5 + 2)
Size:  8.3" x 4.7" x 2.8"    
Weight:  2 pounds 2 ounces Serial No:  6631991
Batteries:  9 AA-size NiCd Date of manufacture:  wk 38 year 1980
AC-Adapter:  Custom Origin of manufacture:  Germany
Precision:  10 Integrated circuits:  TMC0981, see description
Memories:  1    
Program steps:   Courtesy of:  Peter Muckermann

The TI-30 was introduced mid of 1976 and found soon its way to the vision impaired people. The German company Schoenherr developed already in 1975 a refreshable Braille display (see Braillotron TI-2550 II) and introduced in 1978 this Braillotron. 

Dismantling the Schoenherr Braillotron reveals a clever approach choosen for this masterpiece of technolgy.

The first picture of the dismantled TI-30 shows a hand-wired connection between a DSUB-15 connector and some signals of the single-chip calculator circuit. What do we expect? The segment and digit information plus the power supply from the TI-30 brain. TI-30_Braille.jpg (126149 Byte)
The printed circuit board (PCB) of the Braillotron was named TI-30-5. Hope that this is not the revision number...
The PCB carries a lot of electronic components, top of the picture is the power inlet and some rechargable batteries.
Braillotron_2.jpg (164947 Byte)
The design of the Braillotron is straight forward:
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Driver for the refreshable Braille cells.

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Additional batteries for the electronics.

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Conversion from the TI-30 display to the Braille patterns.

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Connector to the TI-30.

Braillotron_3.jpg (124609 Byte)
The refreshable Braille cells doesn't look very complex.
Just 9 digits and the cells of 6 dots each.
Braillotron_4.jpg (15162 Byte)
A side view of the Braille cells reveals the trick:
Each cell consist of six moving pins lifted with small magnets.  
Braillotron_5.jpg (50273 Byte)



Since 1994 the company Schoenherr GmbH refirmed as EHG Handy Tech Elektronik GmbH and introduced in 1985 with the Galixa Speech a scientific calculator with natural voice speech output and later the Galixa Braille a scientific calculator with speech output and a 10-cell braille display. 

This Schoenherr Braillotron was manufactured till 1985.

Another approach to solve the communication with vison impaired people could be found in talking calculators like the TI-66 Calcu-Talk and the Orbit TI-34

Refreshable Braille displays

provide tactile output of information represented on the computer screen. A Braille "cell" is composed of a series of dots. The pattern of the dots and various combinations of the cells are used in place of letters. Refreshable Braille displays mechanically lift small rounded plastic or metal pins as needed to form Braille characters. The user reads the Braille letters with his or her fingers, and then, after a line is read, can refresh the display to read the next line.

Braille: Deciphering the Code

The Braille Cell

The picture below shows you how the dots are arranged in the braille cell for the first ten letters of the alphabet.

Braille Alphabet

Braille does not have a separate alphabet of capital letters as there is in print. Capital letters are indicated by placing a dot 6 in front of the letter to be capitalized. Two capital signs mean the whole word is capitalized.

Braille Numbers

Braille numbers are made using the first ten letters of the alphabet, "a" through "j", and a special number sign, dots 3, 4, 5, and 6.

Larger numbers only need one number sign. The comma in braille is dot 2. Expanding the Code
People sometimes ask if it would be easier to use raised print alphabet letters, rather than dots. When you read about Louis Braille, you'll learn that raised print letters were tried in the early 1800s before he invented braille. However, these letters were very difficult to read by touch, and writing them was even more of a problem. If you ever see an experienced reader's fingers gliding across a page of braille at 100-200 words per minute, you will appreciate the genius of the simple six-dot system. Braille can be read and written with ease by both children and adults. It is truly an invention that is here to stay.

Louis Braille (1809-1852)

Six dots. Six bumps. Six bumps in different patterns, like constellations, spreading out over the page. What are they? Numbers, letters, words. Who made this code? None other than Louis Braille, a French 12-year-old, who was also blind. And his work changed the world of reading and writing, forever.
Louis was from a small town called Coupvray, near Paris. He became blind by accident, when he was 3 years old. Deep in his Dad's harness workshop, Louis tried to be like his Dad, but it went very wrong; he grabbed an awl, a sharp tool for making holes, and the tool slid and hurt his eye. The wound got infected, and the infection spread, and soon, Louis was blind in both eyes.
All of a sudden, Louis needed a new way to learn. He stayed at his old school for two more years, but he couldn't learn everything just by listening. Things were looking up when Louis got a scholarship to the Royal Institution for Blind Youth in Paris, when he was 10. But even there, most of the teachers just talked at the students. The library had 14 huge books with raised letters that were very hard to read. Louis was impatient. 
Then in 1821, a former soldier named Charles Barbier visited the school. Barbier shared his invention called "night writing," a code of 12 raised dots that let soldiers share top-secret information on the battlefield without even having to speak. Unfortunately, the code was too hard for the soldiers, but not for 12-year-old Louis!
Louis trimmed Barbier's 12 dots into 6, ironed out the system by the time he was 15, then published the first-ever braille book in 1829. But did he stop there? No way! In 1837, he added symbols for math and music. But since the public was skeptical, blind students had to study braille on their own. Even at the Royal Institution, where Louis taught after he graduated, braille wasn't taught until after his death. Braille began to spread worldwide in 1868, when a group of British men, now known as the Royal National Institute for the Blind, took up the cause.
Now practically every country in the world uses braille. Braille books have double-sided pages, which saves a lot of space. Braille signs help blind people get around in public spaces. And, most important, blind people can communicate independently, without needing print.
Louis proved that if you have the motivation, you can do incredible things. 


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If you have additions to the above article please email: joerg@datamath.org.

© Joerg Woerner, September 29, 2002. No reprints without written permission.