CYBER word length

[Phil Mason]

In article <363 at yabbie.rmit.oz> rcodi at yabbie.rmit.oz (Ian Donaldson) writes:
>In article <2447 at hcr.UUCP>, mike at hcr.UUCP (Mike Tilson) writes:
> . . .
>The CDC Cyber 170 series uses this concept to advantage with most languages;
>since it has 60-bits (a silly number, I agree), it sets all 'bss' storage to
>0600000000000004nnnnn, where nnnnnn is the address of the storage.  
> . . .
>Ian Donaldson.

The Cyber word length was selected to be 60 bits because of the number of 
exact divisors it has : 2, 3, 4, 5, 6, 10, 12, 15, 20, and 30. As you can 
see, one can pack quite a variety of different length data fields in one word
and not have to worry about your 3 (or whatever) bit fields from extending 
over a word boundary! CDC thought that nobody would ever use more than 64
different symbols for I/O so they made their "byte" six bits long.  Packing
ten of them in a word is convenient, to say the least.

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