DECtape reliability?

Johnny Billquist bqt at
Thu Nov 12 15:29:05 CST 2015

On 2015-11-12 19:49, Al Kossow wrote:
> On 11/12/15 7:27 AM, Jon Elson wrote:
>> LINCtape is essentially identical to DECtape.  I think the directory
>> format is different, but I think the block format is the same.  I think
>> the tapes are wound in reverse order and the order of increasing block
>> numbers is reversed.
> Actually the block format is different. "Obverse Compliment" encoding
> was created for DECtape. LINCtape blocks aren't bidirectional.

Aha. Interesting. I didn't know that the bit patterns of the control 
channel was different.

Curious question then - could most DECtape controllers even read LINCtpae?

I know the TD8E can. The most stupid controller on the planet, but it 
enables you to deal with just about any DECtape format you could 
possibly ever invent.

But other DECtape controllers might not be able to deal with tapes that 
use other codes to indicate what is being read...?


Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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