Chapter 3
VXI-MXI-2 Configuration and Installation
©
National Instruments Corporation
3-15
Configuration EEPROM
The VXI-MXI-2 has an onboard EEPROM, which stores default register
values that are loaded at power-on. The EEPROM is divided into two
halves—a factory-configuration half, and a user-configuration half. Both
halves were factory configured with the same configuration values so you
can modify the user-configurable half, while the factory-configured half
stores a back-up of the default user settings.
Use switches 3 and 4 of the four-position switch at location U35 to control
the operation of the EEPROM. The Restore Factory Configuration switch
(switch 4) causes the VXI-MXI-2 to boot off the factory-configured half
instead of the user-modified settings. This is useful in the event that the
user-configured half of the EEPROM becomes corrupted in such a way that
the VXI-MXI-2 boots to an unusable state.
The Change Factory Configuration switch (switch 3 of U35) 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 4 of U35.
Figure 3-10 shows the configuration settings for EEPROM operation. The
settings of switches 1 and 2 have no effect on EEPROM configuration.
