pma_units -- a unit converter for the PMA430

What is this?

pma_units is a no-frills unit converter; its single purpose is to convert one unit of measure (e.g., imperial gallons) into another (e.g., litres). It was specifically written to suit the landscape screen orientation of the PMA430, but should be useable on other Qtopia devices with landscape screen.

Installation and startup

Download the installer from here. Install this on the Archos in the usual way (e.g., copy to the Documents directory and run the package manager). Start the program from its icon in the `Applications' launcher tab. Source code is available -- please contact me if you want it.

Usage

Not much to it really. Select the category of unit you are interested in (weight, volume, etc) from the Category drop-down list. Enter the amount and units in the `From' box, and the target unit in the `To' box. The program will try to convert whenever there is meaningful data in the boxes -- you don't have to do anything in particular to make this happen.

Implementation notes

There are unit converter programs for the Sharp Zaurus, but all those I tried were tied too strongly the Sharp's portrait display. I have tried to make pma_units better suit the landscape display, by arranging for the display widgets to scrunch up when the virtual keyboard is enabled. You should be able (just) to see all the data entry fields even when the keyboard is in use. This is important in a program like this, because the PMA430 does not provide a thumbpad like that of the Zaurus, so it has to be possible to see what you're typing with the virtual keyboard popped up.

Bugs and limitations

Here are the most obvious ones.

There is no way to customize the unit conversions that are available (except by modifying and recompiling the source). I have tried to include enough to be useful -- currently about 200 units are supported -- but without overwhelming the user interface with a huge list of incomprehensible units. I'm not saying that there are no occasions on which it will be necessary to convert, say, electron volts to egs -- but I am suggesting that there are few occasions when you'll need to do this on a handheld device.
I have tried to be as careful as possible to ensure that the conversion factors are correct. But I'm only human. A particular difficulty is keeping US and UK imperial measures separate. As far as I can tell, all the units that are different between the UK and the USA are labeled as such, and any unit that is not so labeled is the same in the US and the UK. But, again, I can't promise I've done this perfectly.
User interface (such as it is) is in (British) English only. Sorry.

Legal stuff

pma_units is distributed according to the GNU Public Licence. In short, you may do whatever you wish with this code, provided that the original authors continue to be acknowledged, and source code is made available. Please send bug reports, suggestions for new features, etc., to me.

Search

Shameless plug

By the author of this site. Buy on-line from Amazon USA | UK

Editorial

So you want to be a university lecturer? Read this first!

Speak like your boss: new developments in managerese

Computing features

File handling in the Linux kernel: an in-depth look at how Linux handles files, filesystems, and file I/O

All sorts of Linux stuff

Confused about CLASSPATH? answers are here

First steps in EJB using jBoss (recently revised for jBoss 3.2)