Page 0 was Re: [Gllug] BBC and acorn bits

[Adrian McMenamin]

On Sun, 2006-11-26 at 16:34 +0000, Richard Jones wrote:
> On Sun, Nov 26, 2006 at 03:20:39PM +0000, Andrew Black wrote:
> > Page 0 having registers looks like a recipe for registers accidently 
> > getting corrupted (eg a pointer set to 0 or a low value).
> > I am most familiar with the VAX and Alpha architecture where the lowest 
> > page is always (at least under VMS) no access.  I have many times been 
> > saved by processes access violating rather than overwritting data and 
> > plowing on regardless.
> 
> You have to remember that on 8 bit machines it would be very
> unusual[1] indeed to use a C-like high-level language.  Most
> programming was done in machine code without an assembler, and
> less-than-serious programming in BASIC, and neither of those have
> NULL-pointer concerns.  Your machine code program either runs or it
> crashes ...  BASIC of that era doesn't have pointers at all.
> 

Partly that is a question of timing. When I went to University, back in
198blagh 'C' was just beginning to breakthrough to the microcomputer (as
we called them) world - it was certainly easier to get a FORTRAN77
implementation for most micros than it was to get C.

C - like windowing systems - were exotic bleeding edge things at the
time. At least on anything short of a mini - even then the coding was
all in FORTRAN

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