On Tue, 20 Sep 2005 12:57:11 -0700, Barry Gershenfeld wrote:

> When you punched a row of Deletes you could hear it, with all the punches 
> going.  BTW 0x7F is only 7 bits; weren't there 8 bits on the tape? 

Yes, 3 on one side of the sprocket-hole, five on the other, so you couldn't mount it reversed by accident.  
You could feed it through backwards, though, so the tear-off tongue produced a "V" shaped end to the tape, so 
you could see which end was which (you fed it in the direction the "V" pointed).

> You 
> rarely could control the upper bits, though, being dictated by the computer 
> or the inteface. 

On our ASR 33s the eighth was the parity bit.  They used even parity, so NUL (no holes) and Rubout (8 holes) 
gave correct parity.

> Delete was also called "rubout" because of what it did.

Indeed, and thet key that punched it was marked as such.

Cheers,



Howard Winter
St.Albans, England


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