Philips SD-4.00SA CH Service Manual page 28

EN 28 5. SD-4.00SA_CH Test Instructions Mono Board DVD-SD4.00SA_CH
5.11 Diagnostic Nuclei
Each nucleus contains an atomic and independent diagnostic
test, testing a functional part of the DVD player hardware on
component level. Each Nucleus returns a result message to its
caller. Some tests (e.g. generating a colour bar) can only return
an "OK" result. Internal communication will be done via a
uniform interface between the diagnostic Engine, Scripts and
the Diagnostic Nuclei.
The diagnostic Engine can only operate if a certain (minimal)
set of hardware is functioning properly. To test this set of
hardware, a set of basic diagnostic nuclei is embedded in the
DVD player. Each basic diagnostic nucleus will only test that
part of the hardware which is required for execution of the
diagnostic Engine, e.g. a RAM test will only test that part of
RAM that is used by the diagnostic engine. After the Diagnostic
Engine is operational it is possible to do a full RAM diagnostic.
All basic diagnostic nuclei start with prefix 'Basic'.
In the overview each Diagnostic Nucleus consists of a
reference number, a reference name and remarks. Reference
number and name are coupled and one of them is enough for
unique identification.