31 May
2020
31 May
'20
10:44 a.m.
On 2020-05-30 14:18, Boris Gimbarzevsky via cctech wrote:
Chuck, your post just reminded me of how I used
FORTRAN to interface
with my PDP-11 ASM routines when I was doing data acquisition as fast
as possible on a MINC system. Perused my FORTRAN code about 6 months
ago and had common blocks and a routine which took "arrays" which were
essential chunks of PDP-11 memory that I'd use as data buffers and to
access data in my ASM routines directly. Certainly a lot faster than
doing function calls to get at this data but would now be looked at as
very "dangerous" programming.
That's why my (long after retirement) interest is mostly in MCU
programming, currently the STM32F7 series.
The processors have all sorts of interesting memory management hardware
built-in, including storage protection, but few people avail themselves
of it. For me, this allows this once-engineer to get back to playing
with hardware without putting up with the nonsense of a massive
operating system. I find that very gratifying in my dotage.
Cheers,
Chuck