Westinghouse W1642 terminal... any info?

Tony Duell ard at p850ug1.demon.co.uk
Tue Jun 17 22:05:11 CDT 2008


> 
> > Could this thing be doing a modification of the old teletype codes?
> > Sone if the really easier machines used modifications on the Baudaut set.
> 
> Actually as far as I've seen, no Teletype machines actually used Baudot
> code or variants thereof.  They all use variants of Marray code, similar
> to ITA2.

I believe that is correct.

> 
> The only substantive similarities between Baudot code and Murray code

I have an old set of books that describe the 'Baudot Quadruplex' (time 
division multiplexed, done by mechanically rotated seelctors) in great 
detail, and whihc give the character codes (in this machine, you used a 
5-key 'chording' keybboard, not a normal alphanumeric one, so you had to 
know the bit patterns). 

Of course I also haev a Murray/ITA2 table. 

And there are, as far as I can see, no characters that are the same. Even 
the letter/figures  shift equivanlence is totally different (in the 
Murray code, the digits are assigned to the figures shift of Q...P in the 
obvious way, so the top row of a 3-row alpha keyboard becomes the digits 
in figures shift. In baudot code, this is not the case).

> are that both are five-level codes and both use letters and figures
> shifts.

Not even that is idetncial. In Murray code, the 'shift' codes change the 
state of the decoding/printing mechanism, but do noting else. In Baudot 
code, they print a space. That is, there's a 'figures apce' which select 
figures and prints a space, there's also 'letters space' which does the 
obvious. There is no other space character. And there are no carriage 
returen or linefeed codes, becuase the baudot printer printed on a paper 
tape 

-tony



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