The ADC is reset in one of three ways:
1) Power-on reset
2) RESET/PWDN pin
3) RESET command
When the ADC is reset, the device registers reset to default values and the analog-to-digital conversion cycles restart. After reset, the RESET bit of the status byte (bit 0) and of the power register (bit 4) are set to 1 to indicate reset has occurred. Set the RESET register bit to 0 to clear the reset flag. If the RESET bit is then set after clearing the bit, a new reset has occurred.