Giga-tronics Series 12000A, Руководство по эксплуатации

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Front Panel Operation
Publication 31231, Rev. J, October 2003 2-53
Signature Failure Menu
The NVRAM also contains a 32 bit signature word. The signature word has two purposes:
• Change in a new firmware forces the user to initialize NVRAM due to restructuring (Changing the
arrangement of NVRAM without adding new information would not cause a “Checksum Failure”
and a
failure is forced)
• The signature failure may indicate battery failure if it fails every time AC power is totally
disconnected from the unit. If this is the case, the unit needs to be sent back to the factory for
service
Power-Up Preset Menu
This menu below is activated at boot-up by holding down the green “
PRESET
” key during power-up.
This provides the user with the same ability to reset the NVRAM before normal boot-up as the
“Checksum Failure” and the “Signature Failure” menus (when there is no failure); this may be useful in
a situation where boot-up will not complete due to an invalid instrument state when last powered down.
Figure 2-34: NVRAM Signature Selection
Figure 2-35: Power-Up Preset Selection