Requirement:
Details are given pertaining to the definition of generic monitoring parameters, qualifiers and attributes needed to perform the HV, LV, and other hardware control monitoring.
Requirement:
The experimental apparatus parameters monitored by the SVT EPICS implementation are to be defined formally as specific instantiation of generic parameter definitions.
Justification:
Simplify the design, development and use/operation of the software.
Status:
Under discussion
Requirement:
The generic parameter definitions (GPD) will consist of a collection of elements, qualifiers and attributes.
Justification:
A parameter definition necessitates a number of items, some of which are essential, some of which qualify or supplement the information conveyed by the given parameter.
Status:
Under discussion
Requirement:
The GPD will include a label number or identification number.
Justification:
The label will be used for indexing in the software.
Status:
Under discussion
Requirement:
The GPD will include a name consisting of a short keyword.
Justification:
This is the name the user will use to identify the parameter when interaction with the hardware control system.
Status:
Under discussion
Requirement:
The GPD will include a short description of the parameter consisting of a short sentence.
Justification:
The short description conveys more information than a single keyword and hence reduces the ambiguities as to the nature of the parameter.
Status:
Under discussion
Requirement:
The GPD will include a long description of the parameter and associated hardware. The description should include all relevant informations to indicate the nature, fonction and meaning of the parameter. It should also point to other related parameters and additional documentation on the relevant components of the system.
Justification:
The long description will be used as a HELP page for the operation of the monitor.
Status:
Under discussion
Requirement:
The GPD will include a statement of the location of the hardware.
Justification:
Such statement being singled out from the long description will permit quicker and better identification of the components when trouble shouting.
Status:
Under discussion
Requirement:
The GPD will include an attribute to whether or not the parameter is ``seen'', i.e. displayed actively by the user interface. This attribute will have two possible values, YES and NO only.
Justification:
A number of parameter may be defined some of which do not need to be shown to the user.
Status:
Under discussion
Requirement:
The GPD will include an attribute to whether or not the parameter is ``set-able'' by the user.
Justification:
Some parameters cannot be set e.g. air temperature and are read only. Some parameters can be set but should be set at configuration or initialization time and should not under the control of the user.
Status:
Under discussion
Requirement:
The GPD will include a desired state attribute. The state attribute can take as many as three values : ON, OFF, STANDBY.
Justification:
Some hardware elements need to be before OFF or ON under user control. Some harware elements such a HV power supply also can be put on standby.
Status:
Under discussion
Requirement:
The GPD will include a current state attribute. The state attribute can take as many as three values : ON, OFF, STANDBY.
Justification:
Some hardware elements need to be before OFF or ON under user control. Some harware elements such a HV power supply also can be put on standby. A request to change the state of a specific parameter or hardware component may non be effective for a number of reasons. It is thus good pratice to be able to known both what the desired and actual states are.
Status:
Under discussion
Requirement:
The GPD will include a value of frequency at which a given controler should be accessed to read the parameter value.
Justification:
The diversity of the nature of the parameters need under the control of the hardware control system dictates that each be accessed or read at their own speed as dictated by their hardware interface or by the underlying physics processes.
Status:
Under discussion
Requirement:
The GPD will include a value of the ''time out`` to be waited by the system while ``talking'' to a specific interface and waiting for a response.
Justification:
The different hardware controller have different speed. As they may be busy while an access is attempted, it is necessary to define the time interval to be waited.
Status:
Under discussion
Requirement:
The GPD will include a value of the number of retries when a given controler is accessed to read, set, or perform any other action.
Justification:
The different hardware controller have different speed. As they may be busy while an access is attempted, it is necessary to define the number of retries before the apparatus is considered as non responding.
Status:
Under discussion
Requirement:
The GPD will include a variable, possibly user set-able, indicating the desired value of the parameter.
Justification:
Some hardware components need to be set a some selectable value of the parameter.
Status:
Under discussion
Requirement:
The GPD will include a variable containing the current value of the parameter.
Justification:
Some hardware components are used as probes and return some parameter value.
Status:
Under discussion
Requirement:
The GPD will include two variables to specify tolerances on the range of the parameter (low and high values) as read by the hardware.
Justification:
It may be necessary to generate alarms when a parameter is found outside the tolerance range.
Status:
Under discussion
Requirement:
The GPD will include a variable to hold values of associated parameters.
Justification:
This is necessary for instance in the case of the HV supplies which will return a value of current in addition to the high voltage values.
Status:
Under discussion
Requirement:
The GPD will include an attribute used to specify whether the parameter can generate alarms.
Justification:
Some parameters like the voltages can go out of tolerance and should be signaled to the user. Other parameters are used only to characterize the system and need not generate any alarm as they do not have tolerances.
Status:
Under discussion
Requirement:
The GPD will include a qualifier defining the level of alarm generated when the parameter goes out of tolerances.
Justification:
Different parameters going out of tolerance may have different impact on the proper operation of the experiment. It is thus advisable to be able to generate alerts of different levels depending on the severity of the alarm.
Status:
Under discussion
Requirement:
The GPD will include a qualifier or a list of qualifiers defining which actions are to be taken upon the generation of an alarm.
Justification:
Different actions may be possible or advisable. Those of which that can be automated should be initiated automatically by the hardware control. The minimal action to be taken is to log an alert in the log file.
Status:
Under discussion
Requirement:
The GPD will include an alarm in progress attribute used to indicate an alarm has been raised for this parameter.
Justification:
This avoids to generate multiple instances of the same action for the same problem.
Status:
Under discussion
Requirement:
The GPD will include a defer attribute used to indicate the alarm has been defered by the user.
Justification:
Once an alarm condition exists the hardware control will continously report it to the user unless the user declares to be defered.
Status:
Under discussion
Requirement:
The GPD will include a defer delay time. Once deferred, an alarm will be reissued once the delay has elapsed.
Justification:
This is to avoid the user forget an alarm condition once it has been defered.
Status:
Under discussion
Requirement:
The GPD will include a text to describe each error condition that can occur for this parameter
Justification:
The user should be informed clearly of the nature of the apparatus or hardware malfunction.
Status:
Under discussion
Requirement:
The values and ranges of the GPD elements, qualifiers, and attributes can either be defined at configuration time, initialization time, or run time.
Justification:
Justification of requirement
Status:
Under discussion
Requirement:
The GPD will include a password string.
Justification:
The modification of some of the values or attributes should be reserved to specialists and thus should be locked to prevent non-specialists to alter them.
Status:
Under discussion