23 Feb
2007
23 Feb
'07
12:38 a.m.
Tony Duell wrote:
Brent Hilpert wrote:
Em. on partly.
Regardless, it doesn't make the programming any less tortured today.
Or how about this: pretty much every lesson
learned and development made in
languages and programming of the last 4 to 5 decades is missing.
Considering the machine is 3 decades old, that would partly explain that... I assume this plotter ahs a 'listen only'
mode, where it's selected at
power-on and doesn't need ot be addressed. Many HP plotters do.
Of course you lose some functionality if you do that. Most HP plotters
are HPIB talkers too, they can report the current plot size and pen
position -- you could move the pen around with the buttons on the plotter
and use the machine as a primitive digitiser (put a trace from some other
instrument on the plotter bed, then move the carriage to points on that
trace and read them into the computer). You might well not need this though.
The 9815 interface supports the digitising functions regardless of the
(non-)addressability issue, so that functionality is not lost. (My unit
even came with the digitising sight.)
From the schematics, the 9815 interface asserts a
signal on the special
connector on the plotter, said signal ends up on the plotter
microprocessor bus,
so the plotter microproc is distinguishing 9815 vs HPIB and acting appropriately.