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Instrument Security Procedures
Model:
Fluke 5522A

Product Name:
Multi-Product Calibrator

Instrument Description:
High Performance Multi-Product Calibrator

Memory Description:
The Fluke 5522A Multi-Product Calibrator contains two types of storage media.
The first is a flash-based storage media and the second is random access
memory (RAM).
Flash Memory
The flash memory used in the 5522A is a physically block structured device. It
contains three (3) separate blocks. The first block is a special purpose block that
holds a small boot loader. The boot loader software was designed and
maintained by the Fluke Corporation and is preprogrammed into the flash device
for us by the vendor. The boot loader flash memory cannot be easily changed or
reconfigured without special programming equipment. This block is considered
by Fluke to be permanent. If it were tampered with, or otherwise changed, by
anyone other than a qualified software engineer equipped with supporting
documentation from Fluke and external programming hardware, the calibrator
would cease to function. The second block contains the application software for
the 5522A. This block is programmed by Fluke but is otherwise subject to the
same stringent restrictions as the boot code. Additionally, a checksum is
generated and compared on power-up to insure that no changes to this code
have occurred. The third block is logically partitioned by the software into two (2)
mini-blocks. The first contains the calibration constants for the instrument. The
second contains all nonvolatile configuration data for the instrument.
Calibration Constants
Calibration constants are double precision floating-point numbers. The
instrument uses these numbers during normal operations to achieve its
rated output accuracy. Each calibration constant (CCO) has a default
value and a limit. Most limits are within a few percent of the default value.
It's impossible to set a calibration constant to a number outside of its limit.
Calibration constants cannot be accessed directly by a user. They can be
changed during a calibration process. Theoretically, someone could run a
calibration procedure and store numerically encoded data in the
calibration constants. The limits on many of them would obviously
complicate the process though.




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Non-Volatile Configuration Data
Non-Volatile configuration data contains user settings like IEEE address,
serial port configuration, calibration dates, etc. It also contains a string of
a maximum of 64 characters. The string is an IEEE 488.2 standard and
is set using the <*PUD> command. It's queried using the <*PUD?>
Command or from the front panel (see page 6-35 of the Operator Manual
for a complete explanation of these. commands).

To read the contents of the User Report String [PUD], use the
following key strokes from the front panel [see page 3-12 of the
Operator Manual]:

Select the SETUP key on the front panel,
Using the blue `soft' keys under the Control Display, select the
following:
UTILITY
FUNCTNS
Then,
INSTMT
CONFIG
Then,
SHOW USER
REPORT STRING

The Control Display then shows the user report string contents.



Random Access Memory (RAM)
RAM is not directly accessible by the user and its contents are lost when the
power is removed (volatile). RAM is not a likely security risk.

Memory Cleaning Instructions:
The PUD string can be cleared using the <*PUD> command in conjunction with
an empty string. Then queried to insure it contained the empty string. This
would not address any of the other nonvolatile constants but would remove the
most likely threat.
All Configuration Data, including the User Report String, can be set to their
default state using the command and . Any configuration
data that has been modified by the customer would need to be restored,
including the system clock and clock format. This command also clears the PUD
string. This would eliminate any risk of tampering with the Configuration Data
Constants but would not address the Calibration Constants issue. The
Calibration Constants can be reset to their default settings using the
command and . The instrument would need to be calibrated after this
command was issued. This would address the Calibration Constant issue but
would not affect the Configuration Data Constants. All data in the third physical
block, the Configuration Data and the Calibration constants, can be reset to their
default state by using the command and [see page 6-19 of
the Operator Manual for a complete explanation of these commands]. Both the




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and parameters require the calibration switch on the rear panel of
the instrument be set to the ENABLE position.

For re-formatting non-volatile memory, use the following key
strokes from the front panel [see page 3-12 of the Operator
Manual]:

Select the SETUP key on the front panel,
Using the blue `soft' keys under the Control Display, select the
following:
UTILITY
FUNCTNS
Then,
FORMAT
NV MEM
Then,
ALL, or CAL, or SETUP

You must calibrate the instrument after this operation and any modified
configuration data would need to be restored, including the system clock and the
clock format. This is the safest method, but is highly destructive in that it requires
a total recalibration of the instrument.




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