[Simh] pdp11 fails MAINDEC CPU test 14 D0NA

[Paul Koning]

> On Jul 9, 2020, at 8:13 PM, Johnny Billquist <bqt at softjar.se> wrote:
> 
> I know that CPU differences are documented in multiple different handbooks and documents. But I am not aware of any definitive documentation of the PDP-11 architecture like what you seem to refer to Paul (similar to the VARM for VAX). If that handbook could be scanned in (or located anywhere on the net already), it would be a good addition.
> 
> All documentation I know of is addressing various specific models, and the later documentation sometimes contains a table with differences in different implementations. The MicroPDP-11 Handbook for example, do have a list with 52 separate items for different PDP-11 models.
> 
> A slightly different list, in some ways more comprehensive, but lacking information in other dimensions, are available in the PDP-11 Systems Handbook (http://www.bitsavers.org/pdf/dec/pdp11/handbooks/PDP-11_Systems_Handbook_1987.pdf, Appendix A).
> 
>  Johnny


The VAX architecture seems to have been an explicit design effort.  For the Alpha this was even more obvious, where a monstrously large book (certainly 500 pages, maybe double that) was written and reviewed in depth before anything was cast into silicon.  Not so for the PDP11, as you pointed out.

My suspicion is that the PDP-11 architecture handbook was an after the fact effort.  The date (1983) supports that notion.  Also, it's a handbook, a fat paperback like the processor and peripheral handbooks.  I don't know of any internal analog, like DEC Std 032 for VAX.

The document number is EB-23657-18.  They seem to be around for sale, I see some in the $20-25 range which is not bad.  I'm hesitant to let mine out of my sights though I might at some point.

	paul