Re: VAX RPB (Restart Parameter Block)

[Mouse <mouse%Rodents-Montreal.ORG@localhost>]

>> [128 lines of quotes, not trimmed at all]

Would it be too much to ask that you trim quotes down for relevance?
If it hadn't been in this thread I probably would have junked this
message upon getting about 50 lines in without seeing any new text.

>    cons_A_TX: blbc    1001(r11),0x20044f32

> What does this blbc instruction?

Branch on Low Bit Clear.  Reads a longword (which for the VAX means 32
bits, what most other 32-bit machines call a word - VAX doc tries to
keep PDP-11 terminology, which means "word" is 16 bits) from 1001(r11).
If the low (least significant) bit of that longword is set, falls
through to the next instruction; if clear, branches to 0x20044f32.

Conceptually speaking, that is.  I suspect it may actually read only
the low byte, at least when the operand resides in normal memory; that
the operand is defined as a longword is significant for some addressing
modes (though not the one used in the particular case above).

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