PCFR
SAVE(PCFR);
RESTORE(PCFR);
PCFR &= ~PCFR_FVC;
PCFR |= PCFR_PI2CEN;
PCFR |= (1u << 13); /* L1_DIS */
PCFR &= ~((1u << 12) | (1u << 1)); /* L0_EN | SL_ROD */
PCFR |= PCFR_OPDE;
PCFR = PCFR_GPR_EN | PCFR_OPDE;
PCFR = 0;
PCFR = PCFR_OPDE;
PCFR = (PCFR_OPDE | PCFR_FP | PCFR_FS);
PCFR = PCFR_OPDE;