Automatically Adjust HP 100LX Internal Clock

The HP 100LX's internal clock may lose or gain time on a regular basis. Here's a way to automatically correct the time every month.

Let's say you set your 100LX's internal clock to an accurate time source. When you check it in exactly one month you discover that it has lost one minute, 45 seconds (1'45").

You can create a batch file and use it in conjunction with the built-in Appointment Book to automatically correct the time. Here's how.

Create the following batch file and save in the root directory of your C drive (give it the filename ADJUTIME.BAT(ON DISK ICON)).





If you wait until exactly 3:00 a.m. and run this batch file from the DOS prompt, you'll reset the internal clock to 3:01:45 a.m., compensating for the 1'45" your Palmtop lost.

Automate this process by setting an alarm in APPT to run this batch file at exactly 3:00 a.m. on the first Sunday of each month. From APPT press (F2) to Add an appointment. In the Description field of the appointment, enter the following command line:


Tab down to the Start Time field and enter 3am. Tab down to the Alarm field and make sure the alarm is Enabled and the lead time is set to 0.

Now set the alarm to repeat on the 1st Sunday of each month. Press (F8) (Repeat) Monthly. Then Tab down to Monthly Repeat Type and select By Day Position. Tab over once and use the Up Arrow key to select 1st. Tab over one more time and use the Down Arrow key to select Sunday. Press (F10) twice to save the appointment.

If the clock was fast 1'45" per month instead of slow, you would change the time value above to . The .50 at the end of the command line compensates for the 1/2 second it takes to reset the time. I chose the Sunday morning 3:00 a.m. schedule because usage conflicts are not likely.

Other DOS applications should be closed before running this batch file program.

When you run the ADJUTIME.BAT batch file it will change the time. But when the 100LX exits from DOS it displays the message "Press any key to exit form DOS ..." and you have to press a key to return to the System Manager applications, i.e.. APPT, MEMO, FILER, etc. You can suppress this message and automatically return to System Manage by placing a "Q" (quiet) in the Location field in the Appointment/ Event entry screen.

This works very nicely if the clock is slow. However, if the clock is fast, that is it gains time during the month, putting "Q" in the Location field will cause an endless loop. What happens is the batch file runs at 3 a.m., setting the time back to 2:58 a.m. The Q (quiet) suppressed the exit message and caused the 100LX to go back to System Manager where two minutes later it is again 3 a.m. and the time is rest to 2:58. This continues until you delete the appointment or change the batch file.

If you do not put "Q" in the Location field the exit message will not be cleared and the batch file will try to run a second time and will cause another error, "Cannot run program. Press [ESC] to continue." The next time you start the 100LX you will have to press (ESC) to return to System Manager, but the time setting will have been done correctly.

Jose M. Lafora

Hewlett-Packard, SPAIN

[You could use the same technique to create yearly repeating appointments to set and reset daylight savings time changes -Rich.]