HP EPM E4418A, Руководство пользователя

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HP4402.book : chapter2.fm 50 Tue Apr 22 15:20:23 1997
Power Meter Operation
Self Test
2-50 HP EPM-441A User’s Guide
Test Descriptions
This section specifies what is actually checked by each of the tests. Some
of the tests may only be applicable to one method of invocation (for
example, from the front panel). If this is the case, it is specified in the test
description. Most of the tests have an associated error message which is
added to the HP-IB error queue if the test fails. The exception to this is
the bitmap display test. Refer to Chapter 4, “Error Messages” for details
on these error messages.
ROM Checksum
This test calculates the checksum of the firmware and checks it against
the pre-defined checksum stored on the ROM. A pass or a fail result is
returned.
RAM
This test carries out a read and write test on the instrument RAM.
Battery
When the firmware is first downloaded, a known value is written into a
battery-backed memory location. This test verifies that the value is still
resident. It returns a pass if the value is still present, otherwise it returns
a fail.
Measurement Assembly
A measurement assembly is requested to automatically run a self test.
This self test returns either a pass or a fail. A fail can either be produced
by the measurement assembly self test failing or by the measurement
assembly not responding.