Slow Motion Clock

 

Sometimes the sleep mode will not work for some application that needs to keep an eye on some things while radically conserving power.   In that case, you can just slow down the (RC) clock speed by switching a second resistor in or out of the circuit. 

In this example, output RA is either driven high (for high speed mode) or driven tri-state (for low speed mode).   The values shown produce clock speeds of 2 mhz and 60 khz respectively.