15 Ethernet interface
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4registersareused:
-theservicerequestregister(STB)associatedwithitsvalidationregister.
-thestandardeventregister(EventStatusRegister-ESR)associatedwithitsvalidationregister.
Thebits#0,1,2and7oftheSTBregisterareavailableforuseassummarisationmessagesspecific
totheappliance. Eachofthesebitscanbeassociatedwithadatastructurewhosemodelisdefined
andthatmanagestheeventsintheappliancethatmayinduceaservicerequest.
Theusercanconfiguretherecordersothatitloadsthebit#6oftheservicerequestregisterifsome
particularevents shouldoccur.
InRS232configuration,theservicerequestregisterhastobereadregularlytodetectanevent.
Theidentificationoftheeventismadebyreadingthestatusbyte,thentheassociatedevent
register(s).
Statusoftheseregistersatpower-up:
ThecontentoftheSTB, ESRandalarmregistersis systematicallyresettozeroatpower-up(except
thebit#7ofthe ESRthatspecifiesapower-up).
14.4.2.Registersofservicerequest
Statusregister:
Itincludesthestatusbyteoftheappliance.
Thisstatusbytecanbereadincaseofinterrogationwiththe"*STB?"instruction.Inthiscase,the
bit#6isMSS(MasterSummaryStatus)thatcomesfromthelogicaloperationsas showninthe
abovefigure.
Infact,MSSisequalto1whenatleastoneotherbitisequalto1bothinthestatusregisterandthe
validationregister.
CompositionoftheSTBregister:
Thebit#6(value64)includestherecapitulativemessage"MSS"(readingwith"*STB?").
Theservicerequesttakesplaceinthefollowingcases:
-abitofthestatusregisterofservicerequestswitchesfrom0to1whilethe
correspondingbitinitsassociatedvalidationregisteris1,andvice-versa,
-thebit#5ofthevalidationregisterofservicerequestis1andastandardeventoccursin
thefollowingconditions:
-abitofthestatusregisterofthestandardeventsswitchesfrom0to1whilethe
correspondingbitinitsvalidationregisterremainsequalto1
-abitofthevalidationregisterofstandardeventsswitchesfrom0to1
whilethecorrespondingbitinitsstatusregisteris1
-thebit#0ofthevalidationregisterofservicerequestis1andaparticular
eventoccursinthefollowingconditions:
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Logical
OR
STATUSBYTE
REGISTER
SERVICEREQUEST
ENABLEREGISTER
writeby:*SRE<NRf
>
readby: *SRE?
Readby : *STB?

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