Memory Allocation; Types Of Memory And Data Storage; Volatile Memory; Non-Volatile Memory - HP 8719ET Reference Manual

Preset State and Memory Allocation

Memory Allocation

Memory Allocation
The analyzer is capable of saving complete instrument states for later retrieval. It can
store these instrument states into the internal memory, to the internal disk, or to an
external disk. This section contains information on the following subjects:

• Types of memory and data storage

• Determining memory requirements
• Storing data to disk
• Conserving memory
• Using saved calibration sets
Types of Memory and Data Storage
The analyzer utilizes two types of internal memory and can also utilize the internal disk
drive or be connected to an external disk drive:

Volatile Memory

This is dynamic read/write memory, of approximately 4 Mbytes, that contains all of the
parameters that make up the current instrument state. An instrument state consists of all
the stimulus and response parameters that set up the analyzer to make a specific
measurement.
Some data that you may think is part of the instrument state (such as calibration data and
memory traces) are actually stored in non-volatile memory. See

"Non-Volatile Memory"

to
read more about the differences.
Volatile memory is cleared upon a power cycle of the instrument and, except as noted, upon
instrument preset.
Non-Volatile Memory
This is CMOS read/write memory that is protected by a battery to provide storage of data
when line power to the instrument is turned off. With this battery protection, data can be
retained in memory for ≈ 250 days at 70 °C and for ≈ 10 years at 25 °C (characteristically).
Non-volatile memory consists of a block of user-allocated memory and a block of fixed
memory.
The user-allocated memory is available for you to save the following data:
• instrument states
• measurement calibration data
• power meter calibration data
• user calibration kit definitions
• memory traces
• user preset
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