Excellent technical response from Gavin,

I have two questions:

1) How does one (or where does one find info to) mark a program as resident?

2) Is it correct that MPE or HP3000s do not make good real-time machines
because all serial connections are polled rather than hardware interrupt
driven?  Perhaps the designers had imagined some specialty I/O cards that
would handle hardware interrupts?  IIRC someone once told me that neither
the OS nor the hardware were set up to handle hardware interrupts (except
maybe internal hardware, possibly the IEEE488, er... I mean HPIB).
Comments?

-Dave

> -----Original Message-----
> From: Gavin Scott [mailto:[log in to unmask]]
> Sent: Monday, January 08, 2001 11:03 AM
> To: [log in to unmask]
> Subject: Re: nscontrol question
>
>
> Dave writes:
> > Is there a TSR-like feature in MPE?
>
> It is possible to mark code or data as "resident" meaning it
> will remain in
> memory permanently.  This is required for code that would
> execute in an
> interrupt context for example, including all I/O drivers and
> much of the MPE
> kernel.
>
> There's no other "TSR" equivalent feature that I can think of, mostly
> because there's really no place to put such a thing.
>
> > Are there other aspects of MPE (other than being unsuitable
> for real-time
> > programming) that would obviate the need for TSRs?
>
> Nothing other than its being (generally) unsuitable for Real Time
> programming :-)
>
> IIRC, MPE was originally designed to support on-line, batch
> *and* real time
> processing, but the real time stuff got dropped before the first real
> customer version of the OS.
>
> Generally if you really want MPE to do something there's
> probably a way to
> get it to do it, though perhaps not in a way that's easily
> describable using
> terms from other operating systems.
>
> Mike writes:
> > The feature you're looking for is the :ALLOCATE progname
> command.  However
> > it only works on CM programs not on NM.  Use in conjunction with
> > :DEALLOCATE and :SHOWALLOCATE.
>
> The :ALLOCATE command permanently "loads" (resolves load-time external
> references) a CM program but does *not* in any way reserve
> memory for it.
>
> G.
>