[Info-vax] TK50 - this is annoying...

[glen herrmannsfeldt]

Johnny Billquist <bqt at softjar.se> wrote:

(snip)
> But since blocks on a DECtape are numbered when formatting, and the 
> formatting just runs through the tape from start to end, the blocks on 
> the tape will be numbered 0,1,2,3,4,5,6,7,8,9. Which also means that the 
> above suggested idea for writing would mean you need to get a map of 
> which logical blocks maps to which physical blocks. Not forgetting that 
> you need to know when to switch over from forward to reverse operations.

Are they factory formatted, with the block headers never rewritten?
As in the case of 8 inch floppies, it can be done through a remap.

> And in general, this would just about half the speed of your DECtape. 
> Simply because reading all the data on the DECtape now requires you to 
> run over the tape two times, while without this scheme you'll read all 
> the tape by running over it one time.

But, if you include rewind, the time might be the same. 

-- glen