Jeff pontificates:
> Extreme trivia time (may be unique to CIO boxes 950/955/960/980)...
>
> When booting the machine, following the "Interact with ISL?" question,
> you can type-ahead the next answer (e.g., start norecovery <cr>) but
> only the next answer (stuff after the first <cr> is often lost).  And
> similarly, after typing the 'start norecovery' you can go ahead and hit
> <cr> for the date/time prompt.
>
> This has been true for as long as I can remember.
 
I think this goes back all the way to the 930.  Either the console port
actually defaults to having typeahead enabled (and MPE has to explicitly
disable it early in the boot process), or it's just a side effect of the
way the low-level console I/O stuff handles the port (it may not be
smart enough to know when it should be accepting characters and when it
shouldn't).
 
Back when there was no typeahead support im MPE/XL, it was frustrating
to see the system start out doing typeahead but stop as soon as MPE
got going.
 
G.