Talk:LSI-11 chip set

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QBUS only?

I'm trying to work out if the LSI-11 chip set was inherently QBUS only (so I know whether to put it in Category: QBUS Processors). The F-11 chip set isn't QBUS-only, because of the KDF11-U CPU. I was looking at the 'PDP-11/03 user's manual', to see if any QBUS control signals come directly out of the LSI-11 chips (which would imply QBUS only). It appears not - BDIN/BDOUT/BRPLY all come from 'Bus I/O Control Logic', not 'Processor Control Chip', a separate bloc. Looking at the LSI-11 prints, there's a bit of glue logic, but not much. Also, I'm not sure it makes much difference; we used LSI-11's with UNIBUS devices, with a QBUS/UNIBUS converter. So, it probably would have been possible to use the LSI-11 chip set on a 'UNIBUS' CPU with a built-in QBUS/UNIBUS converter.

So I guess I'll put the basic 'xxx chip set's in Category: PDP-11 Processors, and put 'xxx CPUs' into whichever bus categories where it has CPUs on that bus. Jnc (talk) 21:44, 19 November 2021 (CET)