DP Tool Club 8/CDASC08.ISO/VRAC/LAPCLOCK.ZIP/CLOCKS.DOC

Text File | 1993-07-21 | 9.5 KB | 205 lines

BCLOCK - Generic Battery Clock
HBC - "HandBookClock"

Freeware Battery Clocks For Laptops Such As The Gateway HandBook

1. The Generic Version, BCLOCK.

BCLOCK is a merely a teensy TSR battery clock suitable for many
laptop computers.  It is a generic program and will run on any
laptop that I can imagine.  It is a very simple program- the
clock start counts at zero and refreshes every minute.  So if it
goes off screen, fear not, it will return.  Give it a minute to
start up, too.

Unfortunately you cannot turn it off or reset it, and it starts
over each time you boot.  All it really tells you is elapsed
time from when you started it.  This is often good enough,
especially on laptops with a suspend state, where you reboot
seldom.  So, when you are done charging the battery and want to
hit the road or go portable, start up the program, or reboot if
it's already running and then start it up again.  You'll then
always know how many minutes you've put on the batteries.

Why such a simple program?  After all, there are a lot of
programs out there for battery "gas" gauge measurement, and some
of them are pretty sophisticated, allowing for charging time and
a lot of things.  But they are pretty hefty TSRs, 15-20k in
size, and memory is not to be frittered away.  And besides, the
purported accuracy of these programs is a little illusory since
how long the batteries last depend very much on how much disk
access you do, i.e., how much the disk spins/starts up, etc.  So
why gild the lily, let's just have a program that tells you how
much time has passed.  Believe it or not, nowhere in
shareware/freeware land could I find one.  So, here is my own.

If you reboot and then restart the program you'll just have to
make a mental note of total time, in the BCLOCK generic version.

The idea was to keep the program very small and fast, with
little overhead.  After all, we are stealing the timer interrupt
and we could really get ourselves bogged down if the code was
long or slow.


2. The Gateway HandBook Version, HBC.

HBC deals with the reboot/reset problem BUT IT ONLY WORKS ON THE
GATEWAY HANDBOOK.  Do NOT use it on any other computer.  DON'T
TRY IT!  You may blow away your setup information and I will not
be responsible, you have been warned!

You start up HBC just like you would BCLOCK, just type in the
command name and off it goes.  But there is a difference.  HBC
stores its timing information directly in unused bytes of the
computer's CMOS.  This is what makes it so dangerous when used
on the wrong machine!

HBC will retain its time setting through a warm boot
(CTRL-ALT-DEL variety).  So, put it at the end (the end, please,
nowhere else) of your AUTOEXEC.BAT file, and it will start up
every time you boot.  It will not retain its setting through a
cold boot (FN-ALT-DEL) or a hardware reset (the switch in the
hole on the bottom of the unit, the one you poke with your pen
when the machine gets hopelessly hung).

3. Resetting the Clock.

However, HBC allows for a reset by running the program HBCSET.
You will be prompted for hours and minutes.  Enter either zeroes
to restart from the beginning (as in after a full battery
charge), or whatever elapsed time is appropriate.  For instance
if the clock last read 1.09 and you do a cold boot, set the
clock to one hour, ten minutes (an extra minute to allow for the
boot up time).

Now, here is a feature in which I take some pride of authorship.
I have discovered where in the BIOS the HandBook "knows" whether
or not it is on AC or battery power (see the source code if you
are curious).  So, the HBC program is clever enough to increase
elapsed time when you are running on battery power, and DECREASE
elapsed time when you are running on AC power.  What does this
mean for you?  Well, you run on battery power for a while and
build up some time on the display clock.  Then you go and plug
the thing in.  The clock starts running backwards because now
the battery is charging!  And, on the HandBook, it luckily turns
out that a minute of charging gives you back more or less a
minute of battery time.  Logically enough, the clock stops at
zero...  and, in fact, when it reaches zero, it quits
displaying.  Having it sit there reading zero all the time
really doesn't impart much information to you.

All of this is not completely precise, of course, but will give
you a reasonable indication of where you are.

Be aware that if you close the lid the machine goes into suspend
mode.  The clock cannot change but the battery keeps charging.
In such a case, you'll have to reset the clock manually with
HBCSET.  No big deal, you're probably going to go for a full
charge at that point, and you can just set the clock back to
zero.

Now, you still need to know how long the batteries will last,
and this varies a great deal.  It depends on your power
management settings and above all on how often you access the
disk drive.  (I am preparing a companion paper, with program
samples, showing techniques for maximizing both speed and
battery life.  But that's for another day.)  Gateway rates the
battery at 2.5 - 4.5 hours of service, depending upon these
factors.  I find that 2-3 hours is about the limit.  In fact, I
watch the HBC display, and when it goes over 2 hours I start to
get a little cautious.  At 2.5 hours, I'm ready to put in the
spare battery when I reach a point of pause.  (Did you buy a
spare battery?  It's not a bad investment.)

So, you'll need to work with your machine a bit, and find out
what the battery life is for you.  Run HBC and you'll have an
easy time measuring this!

4. Future Features, Perhaps Developed by You.

Some ideas for those who like to tinker: have the resident part
of the program load itself back over the PSP before going
resident.  This might save a few hundred bytes from the resident
(TSR) portion.  And, of course, real tinkerers can try to cut
cycles from the program execution to make it run
faster-better-quicker.  The assembler code is not very elegant
or pretty- I am not Mr. Assembler Programmer.  (The code has one
merit, though: it works.)

What I would like to see automated further is the recharging
timing.  It would be possible to look at the real time clock to
see if the machine had been in suspend mode and adjust
accordingly (when running on AC power).  This would add a bunch
of complications and make the resident code longer, which is why
I didn't do this.  But it's a thought.

Yet another possibility: have the clock count down against
expected battery life.  It would have to count back up when
charging, and stop at the maximum expected life.  I didn't do
this because I think it gives a false idea of how much time is
left, as this varies so greatly with usage.

5. Random Comments

I cannot claim total originality for this program, as the basic
idea came from looking at a disassembly of an ancient minutes
and hours type clock program of unknown origin.  Needless to
say, there is nothing left of this prototype; I've rewritten it
totally.

I hope it is of some use to you, as it seems to be for me.  I do
claim the right to pass this on, as there is no longer any
similarity between this program and the one I used as
inspiration.

The final code is around 624 bytes when resident: not too
onerous, and it runs reasonably well, too.  One could always do
better, of course....

I wrote the HBCSET program in C rather than assembler because I
wanted to do it in ten minutes or less (which is about how long
it took) and I didn't want to mess with keyboard I/O and
character to integer conversions in assembler.  So call me lazy.
The "brand" of C used here is Microsoft Quick C.

Please send any comments to Robert Newell on Software Creations,
Bob Newell on Xevious, BNewell on the Gateway BBS, or by mail to
1825 N. Grandview Lane, Bismarck, ND 58501.  I'd just like to
know if anyone uses this and if it is of any value.  It is of
course freeware, with source code provided.  Just be sure to
share your improvements with myself and others on a similar
freeware basis.

The only restrictions on this program are, that you may not sell
it, and if you modify it and give out a modified version, you
must state who you are and the fact that the program has indeed
been modified.  You also may not remove or alter this
documentation, or the warning file which accompanies the
program.  I don't want to see anyone wipe out their CMOS through
lack of fair warning.

Of course I disclaim all warrantees, expressed or implied, and
assume no liability for anything whatsoever under any possible
legal theory.  If you use this program, you alone are
responsible for anything that may result in any way out of the
use of the program.  If you wipe out your setup information,
trash your CMOS totally, destroy your computer, burn down your
village, or break out in hives- or anything else, for that
matter- deal with it yourself, I'm not responsible.

Support for this program: none promised.  If you find bugs of
course let me know.  Please- no phone calls (period).

6. A Little Tzedakah Can Make a Difference.

As I said, this is freeware, but if you use this program and
like it or find it useful, why not consider donating a few
dollars to a worthy charity in the name of computer hobbyists.
There are people and groups out there that can truly use the
help, and the good p.r. wouldn't hurt us.  And besides that,
you'll feel good about yourself in a very important way.

Bismarck, North Dakota
07/20/93