2.11 BSD on an 11/93 with an CMD SCSI Module

[Bill Gunshannon]

On 3/26/19 3:02 PM, Glen Slick via cctalk wrote:
> On Tue, Mar 26, 2019 at 11:23 AM Bill Gunshannon via cctalk
> <cctalk at classiccmp.org> wrote:
>>
>> The saga continues!!!  I really don;t remember it being this
>> hard back in the good ole' days but then we had lots of real
>> hardware to work with and systems weren't kludges like what
>> I have in my house.  :-)
>>
>> I am currently working with E11 V7.3.  My prime interest is
>> in getting a 2.11 system running so I can use tcopy(1) to
>> copy tape images to my one real tape drive.  It is SCSI so
>> it is going to be TMSCP on the real system.  It is also
>> TMSCP on the E11 system.
>>
>> The problem is I don't seem to be able to do anything on E11
>> to make 2.11 BSD actually have more than one functional tape.
>>
>> I have tried two TMSCP tapes.  I have tried two TMSCP controllers.
>> I have tried one TMSCP tape and various configurations of other
>> tape drives.  the result is always the same.  I hcae tried building
>> a kernel with all the tapes included.  I have tried building kernels
>> with two tapes at a time with different combinations of TMSCP and
>> the others.  None of them ever come up with more than one drive.
>>
>> March 26 05:11:44 init: configure system
>>
>> hk ? csr 177440 vector 210 skipped:  No autoconfig routines.
>> ht ? csr 172440 vector 224 skipped:  No autoconfig routines.
>> ra 0 csr 172150 vector 154 vectorset attached
>> rl ? csr 174400 vector 160 skipped:  No autoconfig routines.
>> tm ? csr 172520 vector 224 skipped:  No autoconfig routines.
>> tms 0 csr 174500 vector 260 skipped:  No CSR.
>> tms 1 csr 164334 vector 774 vectorset attached
>> ts ? csr 172520 vector 224 skipped:  No autoconfig routines.
>> xp ? csr 176700 vector 254 skipped:  No autoconfig routines.
>>
>>
>> I especially don't understand the "No CSR" for tms Unit 0.
>> If I remove the entry for Unit 1 in the E11.ini file then it
>> recognizes Unit 0.  But never both and never any other tape
>> drive.
>>
>> Is there something in 2.11 that I am missing?
>>
>> bill
> 
> Do you need two separate TMSCP controllers, or is that just an
> experiment you were trying and would two tape drive units on a single
> TMSCP controller work equally well for your purpose?

I'm happy either way.  But, from the E11 documentation:
"DEC generally didn’t have more than one tape drive per
TMSCP controller, but as with MSCP disks, E11 has no such artificial 
limits. However this means it may be
possible to configure a system which is incompatible with the PDP-11 
operating system’s TMSCP driver, so it is
best to define a separate controller for each drive anyway."

> 
> Anyway, did you modify /etc/dtab at all? I believe the /etc/dtab file
> in the standard 2.11BSD contains this single entry for a TMSCP
> controller:
> 
> tms ? 174500 260 5 tmsintr # tmscp driver
> 

Mine has two entries:

tms     0 174500 260    5       tmsintr         # tmscp driver
tms     1 164334 0      5       tmsintr         # tmscp driver


> If you want / need two separate controllers I believe you need to add
> another entry for the second controller.
> 
> Also, did you go in /etc/dev and ./MAKDEV tu{unit number} for the
> second tape drive?

Yes, but it didn't work as I would expect being as the init message says
no controller found.

> 
> The 2.11BSD installation guide tells you do this for TMSCP tape drives
> during installation. I believe that will only create device nodes for
> a single tape drive.
> 
> # cd /dev; rm *mt*; ./MAKEDEV tu0; sync
> 
> Without doing some experimenting myself I forget what the actual
> syntax would be for creating additional tape drive units on a single
> or multiple TMSCP controllers.

I have run it again for the additional devices but they end out being
dead.

> 
> What do you see if you do "ls -l /dev/*mt*" ?

ls -l shows all the tape devices get created but they are  none
functional.

> 
>  From the tmscp.4 man page the major / minor device numbers have the
> following meanings:
> 
> major device number(s):
> 
>         raw: 23
>         block: 12
> 
> minor device encoding:
> 
> bit:    |7 | 6 | 5 | 4 | 3 | 2 | 1 | 0|
>          -------------------------------
>           C   C   X   D   D   N   U   U
> 
>         C = Controller # (max of 4 controllers)
>         D = Density
>         N = Norewind on close
>         U = Unit (drive) number (max of 4 drives per controller)
> 

Yeah, got all that.  The problem seems to be init not finding them
during the configure system stage.

And even given the possible confusion over multiple TMSCP controllers,
it doesn't explain why the second I add a TMSCP drive all the others
seem to just go away in the eyes of 2.11.

bill