XIRCREG4_GPR1
PutByte(XIRCREG4_GPR1, 0); /* clear bit 0: power down */
PutByte(XIRCREG4_GPR1, 1); /* set bit 0: power up */
PutByte(XIRCREG4_GPR1, 1 | 4); /* set bit 0: power up, bit 2: AIC */
PutByte(XIRCREG4_GPR1, 0); /* clear bit 0: power down */
PutByte(XIRCREG4_GPR1, 0); /* clear bit 0: power down */