jbn@glacier.STANFORD.EDU (John B. Nagle) (12/08/87)
Has anyone tried Logitec's Modula II with HALO graphics on a PC?
The HALO literature claims that it will work. Does it?
I would like to map a rectangular array of values into a range
of shades of a color, so that I can display map data (obtained from
a ranging sonar) as a range of colors from red to green. Can this be
done using HALO under Modula II on a PGA or EGA type display?
Some questions on Logitec Modula II:
1. Are subranges assigned space appropriately? In particular,
does 0..255 occupy only one byte?
2. How well does concurrency work, if at all? Is it possible
to concurrently operate async ports while updating the
screen?
John NagleBOTCHAIR@UOGUELPH.BITNET (Alex Bewley) (12/09/87)
As far as your concurrency question about async ports goes...
The communication libraries supplied with LogiTech are quite good. The
async routine is run off the IOTRANSFER command. So it will interrupt your
main process as a character is received (but only for a brief moment). All the
characters are stored in a 1K buffer (but it can be expanded if you have the
sources).
If you want, I can send you an example of a terminal program written with
the LogiTech libraries.
Alex Bewleyerja@daimi.UUCP (Erik Jacobsen) (12/12/87)
jbn@glacier.STANFORD.EDU (John B. Nagle) asks in <17237@glacier.STANFORD.EDU> > Some questions on Logitec Modula II: > > 1. Are subranges assigned space appropriately? In particular, > does 0..255 occupy only one byte? No, subranges occupy the same amount of space as the type they are a subrange of. E.g. 0..255 will occupy two bytes. You may use a CHAR or a BYTE, and convert to and from CARDINAL everytime you need to do some caluculations.