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National Instruments Corporation
C-1
C
EEPROM Configuration
This appendix describes how to control the operation of the PCI-MXI-2
onboard EEPROM and how to fix an invalid EEPROM setting.
The EEPROM stores default registers values that are loaded at power-on.
The EEPROM is divided into two halves so that you can modify one half,
while the factory-configured half retains a back-up of the default user
settings.
Controlling the EEPROM Operation
Use switch 1 (FOV) of the four-position switch at location U17 to control
the operation of the EEPROM. Switch 1 determines whether the
PCI-MXI-2 boots off the factory-configured half or the user-configurable
half. In its default setting, the PCI-MXI-2 boots off the user-configurable
half. This switch is useful in the event that the configuration becomes
corrupted in such a way that the PCI-MXI-2 boots to an unusable state.
The TST switch (switch 2 of U17) lets you change the factory-default
configuration settings by permitting writes to the factory settings section of
the EEPROM. This switch serves as a safety measure and should not be
needed under normal circumstances. When this switch is off (its default
setting) the factory configuration of the EEPROM is protected so any writes
to the factory area will be ignored. The factory area is protected regardless
of the setting of switch 1 of U17.
Figure C-1 shows the default settings for EEPROM operation.
Caution
Do not alter the settings of switches 3 and 4 of U17. Leave these switches as
shown in Figure C-1 unless specifically directed by National Instruments.
Figure C-1.
EEPROM Operation Default Settings
U17
FOV
TST
POS
CT
1
ON
23
4
