Time the beeper

[victorf]

I have a piezo-buzzer attached to a zx-24 pin. I wish to sound the buzzer every t - 5 seconds for 5 seconds where t could be 15, 30 or 60 seconds beginning when a specific switch is set on. The buzzer must continue its beep cycle until the switch is set off. I would like the timing cycle to be fairly accurate, say within 0.1 second or so.

How can I do this elegantly?

Any enlightenment will be appreciated.

Vic

[dkinzer]

If not already being used, the interval timer would be useful for this purpose. Here is some sample code that I believe does what you want. The Main() shows how to set the beeper period which can be set to a value of 5 or less for no beeping. The beeper is activated for all but 5 seconds of the period.

The code assumes a buzzer that is activated with a logic zero on an output pin.

[victorf]

Don,

Thanks for the Beeper task code. I guess I was not clear as to how I wanted things to work. I want to set an interval, say 15 seconds, and have the beeper go off at the last 5 seconds of the interval. The 15 seconds is the timing between observations and the last 5 seconds - beeping - is to alert the operator that the end of the period is approaching. I can re-arrange the code to do this.

I am already running a task to handle the keypress strobe from my keypad which you have previously suggested. How will this new task effect the keystrobe task. It is important that the timing interval for the beeper task be within 0.1 or 0.2 seconds of the scheduled period.

Any further enlightenment will be appreciated.

[dkinzer]

I misread your original description but the code can be easily changed to meet your needs.