strange number corruption on pdp11/34

Noel Chiappa jnc at
Fri Jan 30 07:19:08 CST 2015

    > From: Don North

    > So here is the octal print routine in the M9312 console boot prom for
    > the '34:

I'm curious, is that the 'original' source, or is this dis-assembled from the
PROM contents? Is the complete program available somewhere?

    > So I would speculate either 'rol' or 'rolb' are always rotating in a 0
    > bit instead of the c-bit, or possibly the c-bit is stuck at zero.

Yup, good suggestion. And that would likely explain why things boot; I can't
see too many OS's using 'ROLB'!


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