From: Paul Graham <pgraham@cadence.com>
Subject: Re: Disallowing Pre-Defined Operations
Date: 2000/03/17
Date: 2000-03-17T00:00:00+00:00 [thread overview]
Message-ID: <38D2A073.A30FF041@cadence.com> (raw)
In-Reply-To: 38D15537.B06CA311@earthlink.net
Charles Hixson wrote:
>
> Re: Units:
> mks? cgs? or English System? (And is a gallon an Imperial Gallon or a US
> gallon?) Are angles measures in degrees, radians, or mils? (etc.)
VHDL has a syntax for defining units for a given physical type. For
instance:
type distance is range integer'left to integer'right
units angstrom;
nm = 10 angstrom;
mm = 1000_000 nm;
inch = 25 mm;
end units;
Internally a value of a physical type is represented in terms of its
base unit, in this case angstroms. This representation is obtained from
the 'pos attribute. To convert from one unit to another (e.g., for
display purposes) you can do:
variable d : distance; -- vhdl declaration syntax
variable d_inches : integer;
variable d_mm : integer;
d_inches := distance'pos(d) / distance'pos(1 inch);
d_mm := distance'pos(d) / distance'pos(1 mm);
It's also possible to combine different units of the same type:
d := 3 mm + 4 inch + 2 angstrom;
Paul
next prev parent reply other threads:[~2000-03-17 0:00 UTC|newest]
Thread overview: 66+ messages / expand[flat|nested] mbox.gz Atom feed top
2000-03-10 0:00 Disallowing Pre-Defined Operations Charles H. Sampson
2000-03-09 0:00 ` Samuel T. Harris
2000-03-12 0:00 ` Steven Hovater
2000-03-09 0:00 ` Keith Thompson
2000-03-10 0:00 ` Jean-Pierre Rosen
2000-03-11 0:00 ` Tarjei Tj�stheim Jensen
2000-03-11 0:00 ` James S. Rogers
2000-03-13 0:00 ` Tarjei T. Jensen
2000-03-13 0:00 ` Robert Dewar
2000-03-13 0:00 ` Keith Thompson
2000-03-15 0:00 ` Robert Dewar
2000-03-13 0:00 ` dmitry6243
2000-03-15 0:00 ` Charles H. Sampson
2000-03-15 0:00 ` Robert Dewar
2000-03-21 0:00 ` Charles H. Sampson
2000-03-21 0:00 ` Robert Dewar
2000-03-21 0:00 ` Robert A Duff
2000-03-12 0:00 ` claveman
2000-03-12 0:00 ` Robert A Duff
2000-03-13 0:00 ` Tarjei T. Jensen
2000-03-13 0:00 ` Robert A Duff
2000-03-13 0:00 ` Robert Dewar
2000-03-15 0:00 ` Charles H. Sampson
2000-03-15 0:00 ` Tucker Taft
2000-03-15 0:00 ` Paul Graham
2000-03-16 0:00 ` Charles Hixson
2000-03-17 0:00 ` Paul Graham [this message]
2000-03-17 0:00 ` Charles Hixson
2000-03-18 0:00 ` Robert Dewar
2000-03-20 0:00 ` Charles Hixson
2000-03-20 0:00 ` Robert Dewar
2000-03-16 0:00 ` Robert Dewar
2000-03-16 0:00 ` Bryce Bardin
2000-03-16 0:00 ` Tarjei T. Jensen
2000-03-16 0:00 ` mark_biggar
2000-03-16 0:00 ` Dale Stanbrough
2000-03-17 0:00 ` Robert A Duff
2000-03-13 0:00 ` Ted Dennison
2000-03-10 0:00 ` mark_biggar
2000-03-14 0:00 ` Nick Roberts
2000-03-15 0:00 ` Robert Dewar
2000-03-17 0:00 ` William A Whitaker
2000-03-18 0:00 ` Robert Dewar
2000-03-18 0:00 ` Robert Dewar
2000-03-18 0:00 ` Robert Dewar
2000-03-22 0:00 ` William A Whitaker
2000-03-23 0:00 ` Robert Dewar
2000-04-06 0:00 ` Robert I. Eachus
2000-04-05 0:00 ` Marin D. Condic
2000-04-06 0:00 ` Robert Dewar
2000-04-06 0:00 ` Marin D. Condic
2000-04-07 0:00 ` Robert Dewar
2000-04-07 0:00 ` Marin D. Condic
2000-04-07 0:00 ` dale
2000-04-07 0:00 ` Marin D. Condic
2000-04-07 0:00 ` Tarjei T. Jensen
2000-04-07 0:00 ` Marin D. Condic
2000-04-07 0:00 ` tmoran
2000-04-07 0:00 ` Marin D. Condic
2000-04-08 0:00 ` Vladimir Olensky
2000-04-08 0:00 ` Vladimir Olensky
2000-04-08 0:00 ` Dale Stanbrough
2000-04-10 0:00 ` Tarjei T. Jensen
2000-04-15 0:00 ` Niklas Holsti
2000-04-15 0:00 ` Marin D. Condic
2000-04-09 0:00 ` Robert I. Eachus
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