18F23K22

The Oscillator Start-up Timer (OST) is disabled when EC
mode is selected. Therefore, there is no delay in operation
after a Power-on Reset (POR) or wake-up from Sleep.
Because the PIC=AE MCU design is fully static, stopping the
external clock input will have the effect of halting the device
while leaving all data intact. Upon restarting the external
clock, the device will resume operation as if no time had
elapsed.

I haven't found such an explicit paragraph for the dsPIC but
take a look at Fig 48-1 in DS70596A. It suggests there is a
direct line available from OSC1 to Fosc for primaries

Joe=20

--=20
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