PDP-11/10 repair started

-----Oorspronkelijk bericht----- From: Johnny Billquist Sent: Monday, October 05, 2015 5:44 PM To: cctalk at classiccmp.org Subject: Re: PDP-11/10 repair started Ok. I got the initial impression that you only had the CPU in. Thanks for the expanded info. When you don't have any core memory, I wonder if you might need bus grants in those slots as well...? It's not as if they aren't a part of the Unibus... Memory sits on the Unibus, just like everything else, remember? Needs to check further if any special wiring are in place for those slots, though. Johnny ========= I am not sure the "core slots" would need grant cards. The documentation is clear about slot 3-4-5 as SPC, needing grant cards. I never saw any doc where the core memory slots, when optional, but not installed, could be used as an SPC slot. I certainly am Not "trying" that ... I did try the system *with* the core slots filled with the correct boards but the behavior remained the same. To make fault finding not more complex, I removed the core board set.