Can't see the 'scope trace here (server won't let the image thru)...
In the absense of any other information (PIC type, CCP or ECCP, not that it matters), I would guess 1Mhz...
8Mhz / 4 ( crystal vs. Fosc) = 2 Mhz, but still need another cycle to set and/or reset the outputs in the CCP module, hence 1Mhz. Again, don't have enough info, nor datasheets handy.
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