Another RL02 question...

From: Bill/Carolyn Pechter <pechter_at_shell.monmouth.com>
Date: Fri Apr 3 20:56:18 1998

>
> > I may be wrong, but I thought the RL01/RL02 needed a seek to even switch
> > heads to guarantee the #0 and #1 head were on cyl when reading/writing.
> >
> > Anyone else have any recollections/driver sources?
>
> According to the RL tech manual...
>
> Disk Address Register During Read or Write Data Command
> ---
> ...
> Bit 6 Head Select Indicates which head (disk surface) is to be selected.
> A 1 indicates the lower head, a 0 the upper head. The
> correct track (_head_ and cylinder) must have been
> previously selected by a seek.
>
>
> I've just looked in the RL01 printset (the RL02 must be similar), and the
> head select signal comes from a register that only seems to be loaded on
> a seek command. So you _do_ need to do a 'seek' to change heads.
>
> >
> >
> > Bill
>
> Hope that helps
>
> -tony
>

I seemed to remember that from my head alignment days...

Bill
ex-DEC Field Service with hazy (but not completely gone) memory.

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Received on Fri Apr 03 1998 - 20:56:18 BST