Pertec Tape Drive Interface Musings

[Chuck Guzis]

On 06/10/2015 09:40 AM, Al Kossow wrote:

> It happens. Len Shustek's copy of APL/360 has JCL that switches from
> 1600 to 6250 after the label is written. None of my drives can deal with
> that, incl the 9610.
> I've never tried programatic density switching on the 9610, which is
> supported.

Just stick another BOT marker somewhere within the label area, take the 
drive offline and hit LOAD, setting your new density accordingly. 
AFAIK, no drive pays attention to the BOT status while reading.

--Chuck