Startup - Hanna Instruments HI700 Series Instruction Manual

STARTUP

During the automatic startup the Real Time Clock (RTC) is checked to see if a reset occurred
since last software initialization. In this case, the RTC is initialized with the default date
and time 01/01/1998 - 00:00. An EEPROM reset does not affect the RTC settings.
The EEPROM is also checked to see if it is new. If this is the case, the default values
are copied from ROM and then the device enters normal mode. Otherwise an EEPROM
checksum test is performed (the same is performed during EEPROM selftest procedure).
If checksum is correct, normal mode is entered, otherwise the user is asked whether the
EEPROM should be reset.
If EEPROM reset is requested, default values from ROM are stored into EEPROM as would
happen with a new EEPROM.
Note that EEPROM data is composed of setup data and calibration data. As for the setup
data, the calibration data is assigned default values when an EEPROM reset occurs. An
un-calibrated meter can perform measurement, though user is informed that EC or TDS
calibration is needed by means of a blinking "CAL".
When the last calibration data is required, the "no CAL" message is displayed if no
calibration procedure was performed.
Unlike EC/TDS calibration, the user has no information on calibration need for other
ranges, other than the awareness that EEPROM was reset.
After an EEPROM reset, all calibrations (input and output) have to be performed in order
to obtain correct measurements.
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