Introduction and need help bringing some pdp11's back

Nigel Johnson nw.johnson at
Tue Oct 29 20:34:51 CDT 2019

On 29/10/2019 20:37, Chris Zach via cctalk wrote:
> The M9058 can plug in to any general slot in Qbus for power and does not
>> past interrupt or DMA grant.  Bottom/end of the bus is fine.
> Interesting, I didn't realize the RQDX series boards didn't use 
> interrupts or DMA. Does the CPU just poll them endlessly?
RQDX1 and 2 did not pass them but used them. (Maybe not NPG)  I believe 
the RQDX3 did, however.


Nigel Johnson


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