SPCR0: RRST = 1 RINTM = 00 DXENA = 0 CLKSTP = 11 XRST = 1 XINTM = 00 GRST = 1 FRST = 1 SOFT = 1 FREE = 1
PCR0: XIOEN = 0 RIOEN = 0 FSXM = 0 FSRM = 1 CLKXM = 1 CLKRM = 0
XCR0: XIFG = 1