Next project: 11/24. Does it need memory?--Working-ish!

Chris Zach cz at
Wed Oct 28 20:29:39 CDT 2020

> Appendix D in the 003 rev of the /24 TM has the details of the -YA..

Found it. Board is also now working, and I'm selling one of them on 
Ebay. I don't need 4 11/24 CPUs (why do I have these?) Anyway once 
things are up I'll swap a KEF11 and a CIS chipset onto the 24 to bring 
it to full power :-)

> Ironically, although the QBUS uses _exactly_ the same kind of bus grant lines,
> no QBUS processor seems to check their continuity in this way; I habitually
> run my QBUS machines without all the slots filled, and F11 and J11 processors
> all run fine with open grant lines (after the last card that uses
> interrupts). I guess DEC found out the hard way that that check wasn't
> useful!

True, and while the problem may not be the bus per se, the 
implementation of a pdp11 on Q-Bus just seems to have less of these 
annoyances. No biggie, just the usual stuff.

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