HP Integral PC Manuals

[Tony Duell]

> 
> Yes V1.0.0 I think the same it's just designed to keep the motors running.
> Maybe to get the media running before the heads touch it, to prevent 
> start/stop spots ?

Of course this is one of the few 3.5" drives that has a head-load 
solenoid (and yes, that is controlled 'correctly'). So at least disk/head 
wear will be fairly minimal. It is curious that having provided a 
motor-control signal then essentially it's not used (min you, it appears 
that the Intgral hardware would support 2 floppy drives, and that 
facility, AFAIK, was never used)

I am not sure what the Sony drive spec says about starting/stopping the 
spindle motor with the heads loaded. I've not heard it's a problem in 
other (floppy) drives, though.

> Well the ability to make errors is what makes us human ;-)
> The hartbeat should it be some kind of watchdog signal or a sync for 
> realtime processing ?

It usspect it's the task-switch signal, etc. When the machine is 'idle' 
(no I/O going on), IR1 is the only interrupt line to be doing anything.

-tony