Re: Address of second TMSCP controller

[Paul Koning <paulkoning%comcast.net@localhost>]

> On Jan 26, 2021, at 7:57 AM, Mouse <mouse%Rodents-Montreal.ORG@localhost> wrote:
> 
>> In addition to a broken TK70, which is being recognised fine by
>> NetBSD as mt0, I want to use a 40/80GB DLT on a Dilog SQ703 SCSI
>> TMSCP adapter.
> 
>> NetBSD doesn't recognise it on booting.=C2=A0 I don't see anything
>> about addressing in the hardware wiki, does anybody know the address
>> where NetBSD looks for a second controller?
> 
> As far as I can tell, it doesn't.  The only TMSCP device I see is
> 
> mtc*		at uba? csr 0174500	# Tape MSCP ctlr
> 
> Since there's no other mtc in sight, I rather wonder why it's mtc*
> rather than mtc0 - perhaps for machines with multiple buses?
> 
> I imagine you could add a second mtc line to your config at whatever
> address you put your Dilog card at.  ISTR that DEC had a bunch of rules
> for such addresses - the phrase "floating CSR space" comes to mind -

Right.  In the DEC rules, this is a "first unit fixed, rest float"
device, just like the MSCP disk controllers.  The float CSR rank is 30.
Does NetBSD do the floating CSR address algorithm?  If not, yes, just
pick some address and tell the OS what it is.

	paul