On 2019-06-24 20:09, Mark Pizzolato wrote:
On Monday, June 24, 2019 at 10:36 AM, Johnny Billquist wrote:
On 2019-06-24 15:12, Paul Koning wrote:
On Jun 23, 2019, at 4:44 PM, Mark Pizzolato <[email protected]>
wrote:
...
As Tim mentioned, some of the hardware that is modeled did indeed
allow arbitrary unit numbers (via plugs on the drive).
Some 14 months ago support was added to provide per drive Unit plug
values to be set. This is set via:
sim> SET RQn UNIT=plug
plug can be any value from 0 thru 65534. Default unit plug for each
RQn is n.
I know of 8 bit unit number plugs, in the RA series drives. I haven't run into
16 bit unit numbers.
The field in the MSCP packets provides for 16 bits.
Yep. I wonder when I will ever learn to read the manuals instead of
trying to trust my memory. It's 16 bits.
And I can't find anything about subunit numbers, so I wonder where I
remember that from?
RA60, RA80, RA81 and RA82 had these large unit plugs, with 8 pins on them
that you could cut, so the largest possible unit number on those were 255.
However, RA90 and RA92 have a digital display, which you program the unit
number on, and they go to 4095.
RA70 have 8 dip-switches to select unit number.
RA71, RA72 and RA73 must have a front panel, which sits on a SA7x box.
That front panel is also digital, and you have four displays - one for each
drive
in the box. But even though they also could hold 4 digits, the unit numbers for
these drives wrap at 255.
There may be physical limitations on some hardware for different unit numbers
with different drives, but the MSCP protocol and related software clearly
support
a 16 bit value.
Right. Like I said, some drives have an arbitrary or physical limitation
to only 8 bits. But MSCP obviously supported larger numbers. And I was
wrong saying 12 bits. It's clearly 16 bit if you read the documentation.
Johnny
--
Johnny Billquist || "I'm on a bus
|| on a psychedelic trip
email: [email protected] || Reading murder books
pdp is alive! || tryin' to stay hip" - B. Idol
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