strange number corruption on pdp11/34

Johnny Billquist bqt at
Tue Jan 27 17:13:42 CST 2015

On 2015-01-28 00:05, Noel Chiappa wrote:
>      > From: Johnny Billquist
>      > If it comes as far as booting RSX as well as XXDP, there can't be
>      > anything seriously wrong with the CPU...
> Yeah, I see your point, but why all the zeros, then? That's what I could't
> work out.
> Anyway, it should be really easy to make sure e.g. ASH, MUL and DIV are
> working; it's vaguely plausible that one of them is broken. (Unix V6, I think,
> might even boot even if MUL was broken. I know the bootstrap uses DIV, to
> calculate the cylinder in the disk driver.) If not, cross that off the list,
> and try the next thing... Which is?

Is noone paying attention to the fact (and my previous comment) about 
using 0 for CSR and vector???


Johnny Billquist                  || "I'm on a bus
                                   ||  on a psychedelic trip
email: bqt at             ||  Reading murder books
pdp is alive!                     ||  tryin' to stay hip" - B. Idol

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