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3.11 Memory
The waveform generator uses a non-volatile FLASH memory for storing arbitrary waveform data and front panel
settings. Up to 4,000,000 points Arbitrary waveform and 50 front panel settings are stored. These front panel
settings can be used to store starting address and lengths of many different waveforms stored in memory as reference
points for quick recall.
Because it is impossible to guarantee 100% of the time against loss of stored data, you should maintain a record of
the data stored in memory so that you can manually restore such data, if necessary.
3.11.1 Nonvolatile Flash (Arbitrary Waveform Memory)
The FLASH stores the arbitrary waveform memory at power off, which the waveform generator uses to store the
data points that make up an arbitrary waveform. This memory is a matrix 16383 x 14,000,000 that you use to plot
your arbitrary waveforms.
The FLASH also stores the settings storage buffer, which the waveform generator uses to store up to 49 front-panel
setups. For more information about the settings storage buffer, see SETUPS key earlier in this section.
Because it is impossible to 100% guarantee against loss of stored data, you should maintain a record of the data
stored
in memory so that you can manually restore such data, if necessary.
3.11.2 Dynamic RAM
The DRAM stores waveform output. For arbitrary waveform output, the waveform generator loads the selected
contents of the FLASH (arbitrary waveform memory) into the DRAM. In order to save the arbitrary edited data in
the DRAM memory, the instrument will display a message " SAVE DATA" after each modification of the arbitrary
waveform in the EDIT menu.
3.12 Displaying Errors
At power-on, the waveform generator performs a diagnostic routine to check itself for problems. If the diagnostic
routine finds an error, an error message is displayed. The waveform generator also displays error messages when
front-panel settings are either invalid or may produce unexpected results.
Error messages for Model 406 and 4079
Message
Text
Cause
Out of range
Attempt to set variable out of instrument limits.
Setting conflict
Can't have this parameter set with some other.
Trig rate short
Internal trigger rate too short for wave/burst.
Empty location
Attempt to restore non existent setting.
SCALE too high
Attempt to set scale too high for current dot value
Protected RAM
Attempt to write to protected RAM range.
RAM error
Error in testing RAM.
Save RAM
New firmware installed.
Must divide by 4
Predefined wave length must be divisible by 4.
Must divide by 2
Predefined wave length must be divisible by 2.