17 Jan
2023
17 Jan
'23
8:02 p.m.
On Tue, Jan 17, 2023 at 10:17 AM Bill Degnan <billdegnan(a)gmail.com> wrote:
On Tue, Jan 17, 2023 at 8:39 AM Bill Degnan
<billdegnan(a)gmail.com> wrote:
I am working to understand a TU56 in my
possession that came from an
unknown environment. A connecting cable that came with it reads "PDP9" on
one end so I wondered if this is actually associated with the TU56 or just
sitting in the same box before the TU56 came to me. I have read here:
https://gunkies.org/wiki/TU56_DECtape_Transport
That one can have a TU56 with a M531 or a G742 to serve as a bus
converter. THe M531 is for situations where one has a negative logic
controller and the G742 is for when one has a positive logic controller.
Jumping a few steps ahead, if the TU56 was attached to a PDP-9, would it
use a G742 if one tried to attach a TU56 to it? I feel as if the G742
would be used if the TU56 was intended for a PDP8 and not a PDP11, right?
I searched the web and will continue to research but I thought I'd ask
experts here. No, I don't use ChatGPT.
Bill
<snip>
I consolidated my findings here:
https://vintagecomputer.net/browse_thread.cfm?id=788
Basically think that the TU56 can connect to a PDP-9 as long as the correct
bus connector is used. There is documentation how to attach a PDP-9 to a
TU55, which should be the same as the TU56 where it counts in this
situation. Because the 9 is a negative logic system, a M531 would be used
to connect with a (not sure PN) cable OR you'd use a G742 bus connector and
a W850 adapter + cable.
So yes, it's possible that my TU56 was attached to a PDP-9 on the other
end, at least for some period of time.
Bill