Re: Closed system (was: PC connection via twinax ?)

Doug:
        I believe most of the functions were used in a device called the 
"transition data link", device, which enabled you to transfer the entire
S/36 to a configured M36 on the /400.
        Largere outfits, with a lot of 36s, bought one, and used it themselves,
otherwise, theu used it thru a third party support arrangement.
        It would be interesting to know, just how widely used this process
still is, or (dare I ask), how many older model s/36 boxes are still out
there.
        If I am correct, the s/36 was a very popular, and widely used business
os, right into the 90's.
Shields

Douglas Handy wrote:
> 
> Simon,
> 
> Steve wrote:
> >>Back in the day when converting from the s36 to 400, there was an ibm
> >>product that allowed data transfer thru the twinax port.  Is it known how
> >>to do that?
> 
> You asekd:
> >No idea of the top of my head.  But why would that be needed now?  There are
> >better file transfer methods available.  What was at the other end of the
> >twin-ax port to receive the transferred file?
> 
> The box was simultaneously connected via twinax to two different hosts.
> Basically you took a WS ctl port from host A and a port from host B and ran 
>them
> to input ports on the box.  Then there was an output twinax port where you 
>would
> put at least one dumb workstation.  Or cable through to more WS's or twinax
> printers -- up to the port limit of 7 of course.
> 
> The box was a little like a a twinax A/B switch -- but it kept both hosts 
>active
> at the same time and enabled a hot key sequence (on dumb terminals!) to switch
> between hosts.  Each user on the port could could hot key independently, and
> address 0 could also switch printers between hosts.
> 
> This made for a good way to perform compatability testing and some initial
> training of users prior to cutover.  And it made a much better A/B switch 
>than a
> real A/B switch.  I know a software house that used one for years as a
> replacment for A/B switches -- maybe they still use it.  (Why anyone would
> rather program from a dumb terminal rather than a PC is beyond me, but that's
> another story...)
> 
> The second function the box provided (other than dynamic A/B switching) was 
>data
> transfer.  Software was provided for the S/36 and AS/400 which would use 
>display
> sessions as a bi-directional data pipeline.  Many times in those days you did
> not have a compatible tape drive on each machine.  This avoided the need to 
>use
> tape conversion services.  And you could do something like refresh all your 
>data
> files every night from the old production machine to your new box.
> 
> You could dedicate up to 6 twinax addresses for data transfer.  It would
> configure those as 3180's in order to get 27x132 support so each "screenfull" 
>of
> data would be larger and thus improve throughput.
> 
> The original model was over $5K, but never sold well.  In 1990 they started
> bundling it with some incentive packages to get people to move from the 36 to
> the 400.  (I think IBM was overstocked on them...)  That's how I got to use 
>one
> for a conversion.  Worked quite well considering the machines had no other
> compatible data transfer method.
> 
> I think later they did a different model which did not have the A/B switching
> features and was strictly a data transfer box.  For old S/36's without network
> connections (most of them!) and without compatible tape drives, this may still
> be a viable data transfer method.
> 
> Doug
> 
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-- 
Best Regards
Ken Shields
Home phone: 905 404-2062
Bus  phone  905 725-1144 (326)