In a message dated 96-10-09 14:24:22 EDT, you write:

>How about the PWM on board the 'C84 otherwise a NE555 with a few RC networks
>and a couple control lines from the PIC could do it. I have an old
>ultrasonic pest repeller that uses the 555 that way.

Instead of a NE555, you could use PIC12C508 (8-pin PIC) and NO external RC
networks.  With 6 I/O available, you could even implement multiple timers.

Mark A. Corio
Rochester MicroSystems, Inc.
200 Buell Road, Suite 9
Rochester, NY  14624
Tel:  (716) 328-5850 --- Fax:  (716) 328-1144
http://www.frontiernet.net/~rmi/

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