Trying to get my RLV11 working

Johnny Billquist bqt at
Thu Oct 29 13:22:25 CDT 2015

On 2015-10-29 18:44, Noel Chiappa wrote:
>      > From: Ben Sinclair
>      > the bc80m cable .. which I believe is a ribbon type of connector with a
>      > ground strap on one end, then a round cable to the berg connector for
>      > the back of the RL02. I think it's the cable pictured here:
>      >
> Yes, that's the cable. But there's no ribbon cable anywhere in it: the
> individual wires from the round cable go directly to the Berg (aka Du Pont)
> female connector, which plugs into the male Berg header on the board.
> The other end does not have a Berg connector, it's some sort of wierd-ass
> connector that I don't know the proper name for. (The RK0[67] also uses them,
> and I think maybe the MASSBUS too?)

The Massbus connector is similar, but about three times the size.

>      > Early revisions only supported 18 bit addressing, but later models
>      > supported 22 bit addressing. But how that is reflected in the micro-ODT
>      > on a KDF-11 I don't know.
> I already bitched about this! Although it supports Q22 _on the bus_, their
> ODT only supports Q18. There's no way to fiddle with high memory, except
> via program!

Yuk. :-)

>      > I don't even know if it's actually micro-ODT, or some more primitive
>      > console mode on that CPU.
> AFAIK, it's the same ODT as all the other QBUS -11's (03, 73, etc - although
> the /03 has the 'L' bootloader command that none of the others do, along with
> a couple of other odd minor ones like '@').

I certainly seem to remember that some machines had a rather different 
interface than the Micro-ODT one, but maybe they were all various early 
Unibus-machines. Can't remember for sure. I tried to stay away from 
machines that had the serial console interface to the hardware. I prefer 
front panels. :-)


Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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