AR4000 User’s Manual
24
LLL004001 – Rev 2.7
12. Configuration and Non-Volatile Storage
12.1 EEPROM Operation
The AccuRange 4000 stores its configuration settings in non-volatile memory
(EEPROM). Factory configuration values are stored in the EEPROM upon
shipment and may be restored at any time using the Reset Configuration
command, or by holding the push-button down while powering up the interface.
The configuration commands do not automatically store the changes to the
EEPROM. The Write command is used to make these changes permanent. The
Write command stores all configuration information, so it can be used once after
making several changes. The Read command is used to restore the values from
EEPROM and will overwrite any changes not saved with the Write command.
If the interface is unable to read the configuration data on power up or when the
READ command is used, the message “EEPROM VALUES INVALID”. is sent
over the serial port as the present baud rate, or at 9600 baud if the failure occurs
on power-up. This will happen if the data has been corrupted due to a power
failure during EEPROM write or some other reason. The sensor will then halt,
with the indicator lamp flashing, until the switch is pressed. When operation
continues, the sensor will be configured with the factory default settings.
The Write command should not be issued repeatedly under computer control in
the course of normal operation, since the EEPROM’s expected lifetime is
100,000 data changes.
Calibration data is also stored in the EEPROM, but cannot be changed by user
commands. If the calibration data becomes corrupted, the message “EEPROM
CALIBRATION DATA READ FAILED” is sent over the serial port. The sensor
will then halt, with the indicator lamp flashing, until the switch is pressed. When
operation continues, the calibrated range output will likely be incorrect, and
sensor operation will be impaired. Contact Acuity for assistance.