PWM and MEMORY

[mackrackit]

The 12F683 has an EEPROM.

Depending on how often your light signal changes, write that value to the EEPROM. When the chip boots have it read the EEPROM first to get the value for PWM.

Or if this is only for scheduled shut downs write a shut down sequence to save the value.

--edit--
While I was typing the question was answered...