Timer0 is the Energizer Bunny of the 14-bit PIC world.
It keeps going and going .... and there is no on/off bit.

The prescaler value and assignment is in the OPTION_REG register.
When it says the prescaler will be cleared, it means the value that the prescaler has counted so far. Not the division ration used by it.

Once you set the prescaler to 1:8, it'll stay there till you change it.
There are also times I'm going to want to stop the timer, read the value, then perhaps re-start it.
Not with Timer0.
It is possible to stop it by switching the clock source to T0CKI (PORTA.4), but that means you can't use that pin for anything else.
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