Epics record reference 3 -- fields common to all records

This section contains a description of the fields that all record types have . These fields are in dbCommon.dbd In the definition of .

Operation display parameters

NAME The field contains the record name , It's in one. EPICS The channel access namespace must be unique . This name is provided by the program developer and is a way to distinguish a particular record . Longest name 60 Characters and use only these limited characters ：

 a-z A-Z 0-9 _ - : [ ] < > ;

DESC The field can be set as a meaningful description of the purpose of the record . The longest is 40 Characters .

Field	Summary	Type	DCT	Default	Read	Write	CA PP
NAME	Record name	STRING [61]	No		Yes	No	No
DESC	describe	STRING [41]	Yes		Yes	Yes	No

Scan field

These fields contain information about when and how a record runs . Some records have and have unique fields that affect how they work . In this section, each record lists these fields and explains .

SCAN Field Specify a scan period for periodic records or a scan type for aperiodic scan records . stay menuScan.dbd We can find SCAN Default set of fields .

The options available from this menu are ：

• passive Corresponding to records triggered by other records or channel access
• Event Corresponding event driven scanning
• I/O Intr Corresponding to interrupt drive scanning
• A periodic scan interval set

Through local replication menuScan.dbd And add more options as needed , Be able to serve their own IOCs Define more periodic scan rates . The periodic scan rate should normally be defined sequentially after other scan types . The longest cycle occurs first . Can use a second/seconds, minute/minutes, hour/hours or Hertz/Hz The unit string of specifies the scan period . If you include units in the option string , Use seconds . for example , These rates are all valid ：

 1 hour
 0.5 hours
 15 minutes
 3 seconds
 1 second
 2 Hertz

PINI Field specifies that the run... Is recorded at initialization time . If it is set to... In the database configuration YES,( Before starting a normal scan task ) stay IOC Run this record once during initialization .

PHAS Field pairs in a specific SCAN Sort records in group . It has no meaning for passive recording . designated phase All records are higher in phase Run before recording values . Use linked passive records to implement a running sequence instead of a phase Numbers are a better habit .

EVNT Field specifies an event number . If SCAN Field set to Event, Use the event number . When it comes to EVNT Carry out a post_event Invocation time , The scan type... Will be run Event And the same EVNT Worth all the records . Yes post_event Have to call ：post_event(short event_number).

PRIO The field is run SCAN=I/O Event Set of and asynchronous record completion task assignment scheduling priority .

DISV Field specifies a "disable value". When the value of this field is equal to DISA Value of field . Record run cannot start , This means that this record is disabled . Be careful ： Access through database or channel puts Can change the field value of a record , Even if this record is disabled .

DISA The field contains the and DISV The value of comparison , Decide whether this record is disabled . stay IOC Before attempting to run this record , from SDIS Link to DISA Field to get a value . If SDIS Not set , It may be set by some other method DISA To enable or disable this record .

DISS Field defines the... Of this record "disable severity". If this field is not NO_ALARM And this record is disabled , This record will be placed in a state of DISABLE_ALARM And this serious alarm .

PROC Field ： This field of a record is written to , Run this record .

LSET Field contains the lock set to which this record belongs . Use to enter , Output or forward database links in any way. All records linked together belong to the same lock set . stay IOC The lock set is determined during initialization , And adding 、 Updated when removing or changing database links .

LCNT Field calculation during continuous scanning dbProcess The number of times this record was found to be active , Even if ：PACT by TRUE. If dbProcess Found this record active MAX_LOCK Time ( Current setting 10), It produces a SCAN_ALARM.

PACT Field ： When records are active ( function ), This field is true . In asynchronous record , From the start of the record run to the asynchronous completion ,PACT Can be true . as long as PACT It's true ,dbProcess This record will not be called to run the routine . of PACT See the program development guide for the usage of .

FLNK A field is one that points to another record (“ The goal is ” Record ) Link to . As long as the provided target records SCAN The field is set to Passive, Run a setup FLNK Field will be recorded at the end of the first record run ( But in PACT Before being cleared ) Trigger target record operation after . If FLNK Field is a channel access link , It must point to the... Of the target record PROC Field .

SPVT Field for internal use by the scanning system .

Field	Summary	Type	DCT	Default	Read	Write	CA PP
SCAN	Scanning mechanism	MENU	Yes		Yes	Yes	No
PINI	stay iocInit run	MENU	Yes		Yes	Yes	No
PHAS	scanning Phase	SHORT	Yes		Yes	Yes	No
EVNT	Event name	STRING [40]	Yes		Yes	Yes	No
PRIO	Scheduling priority	MENU	Yes		Yes	Yes	No
DISV	Disable value	SHORT	Yes	1	Yes	Yes	No
DISA	Disable	SHORT	No		Yes	Yes	No
SDIS	Scanning Disable	INLINK	Yes		Yes	Yes	No
PROC	Forced operation	UCHAR	No		Yes	Yes	Yes
DISS	Disable Alarm Sevrty	MENU	Yes		Yes	Yes	No
LCNT	Lock count	UCHAR	No		Yes	No	No
PACT	Record active	UCHAR	No		Yes	No	No
FLNK	Forward run link	FWDLINK	Yes		Yes	Yes	No
SPVT	Scan private	NOACCESS	No		No	No	No

Alarm fields

STAT The field contains the current alert status .

SEVR The field contains the current alert severity .

AMSG The string field may contain more detailed information about this alert .

STAT, SEVR and AMSG Fields hold alert information as seen outside the database .NSTA,NSEV and NAMSG Fields are accessed by the database during the record run , Record support and device support routines are used to set alarm status and severity values and message text . When any software component finds an alarm condition , It calls one of these routines to register this alert ：

 recGblSetSevr(precord, new_status, new_severity);
 recGblSetSevrMsg(precord, new_status, new_severity, "Message", ...);

These routines check the current alert severity and update if appropriate NSTA,NSEV and NAMSG, So during the record run up to now , They are always associated with the highest severity alert . file alarm.h Defines the available alert states and severity values . At the end of the recording run , These fields are copied to STAT,SEVR and AMSG Field and alarm monitoring is triggered .

ACKS The field contains the highest unacknowledged alert severity .

ACKT Field specifies whether it is necessary to acknowledge the transient alarm .

UDF Field indicates whether the value of this record is undefined . This is usually caused by a failure in device support , actual ： This record has never been run , perhaps VAL The field currently contains a NaN( Non numerical ) perhaps Inf( Infinite ) value .UDF Default TRUE, But it can be set in the database file . writes VAL Field records and device support routines are generally responsible for setting and clearing UDF.

Field	Summary	Type	DCT	Default	Read	Write	CA PP
STAT	Alarm status	MENU (menuAlarmStat)	No	UDF	Yes	No	No
SEVR	Alarm severity	MENU (menuAlarmSver)	No		Yes	No	No
AMSG	Alert message	STRING [40]	No		Yes	No	No
NSTA	New alarm status	MENU (menuAlarmStat)	No		Yes	No	No
NSEV	New alert severity	MENU (menuAlarmSver)	No		Yes	No	No
NAMSG	New alert messages	STRING [40]	No		Yes	No	No
ACKS	Alarm Ack Severity	MENU (menuAlarmSver)	No		Yes	No	No
ACKT	Alarm Ack Transient	MENU(menuYesNo)	Yes	YES	Yes	No	No
UDF	Undefined	UCHAR	Yes	1	Yes	Yes	Yes

Device fields

RSET The field contains the address of the record support entry table .

DSET The field device supports the address of the entry table . The value of this field is in IOC It is determined during initialization . Record support routines use this field to find their device support routines .

DPVT Field is used for the private use of the device support module .

Field	Summary	Type	DCT	Default	Read	Write	CA PP
RSET	RSET The address of	NOACCESS	No		No	No	No
DSET	DSET Address	NOACCESS	No		No	No	No
DPVT	Device private	NOACCESS	No		No	No	No

Debug fields

TPRO Fields can be used to track record runs . When this field is non-zero and the record is run , A trace message will be printed for this record and any other records triggered by a database link from this record in the same lock set . The trace message contains the name of the running thread , And the name of the record being run .

BKPT Field indicates that there is a breakpoint setting in this record . This supports setting a debug breakpoint in the record run . Use this to support STEP Run through the database .

Field	Summary	Type	DCT	Default	Read	Write	CA PP
TPRO	T Tracking runs	UCHAR	No		Yes	Yes	No
BKPT	The breakpoint	NOACCESS	No		No	No	No

Other fields

ASG The string field sets the name of the access security group used for this record . If left blank , This record is placed in the group DEFAULT.

ASP Field is private for accessing the security system .

DISP Field control comes from IOC External puts Whether it is completely allowed to modify the fields of this record . If the field is set to TRUE, Except for fields DISP Self puts Outside , Ignore all... Directly to this record puts.

DTYP Field specifies the device type for the record . Most record types have their own set of device types , Again IOC Specify them in the database definition file of . If a record type does not call any device support routines , Don't use DTYP and DSET Field .

MLOK Field contains a mutex , When the monitoring list corresponding to this record is accessed , It's being used in dbEvent.c The monitoring routine in is locked .

MLIS Field holds a linked list of customer monitoring connected to this record . Each record support module is responsible for triggering monitoring for any field that changes due to record operation .

PPN The field contains a putNotify callback The address of .

PPNR Field is PutNotify Contains the next record .

PUTF Field if dbPutField Causes the current record to run , It is set to True.

RDES Field contains dbRecordType The address of .

RPRO Field specifies that the record will run again when the current run ends .

TIME Field to save the timestamp of the last time this record was run .

UTAG Field is used to save a site-specific 64 User tags only , It is related to the timestamp of the record .

TSE Field specifies the mechanism used to obtain the timestamp .'0'： Call... As before get time.‘-1’： Call timestamp driven bin and use best available source .‘-2’： The device supports time stamps from the hardware and optional user tags . Again 1-255 Between refers to requests generalTime The last time the event occurred .

TSEL Field contains an input link to get the timestamp . If this link points to a recorded TIME Field , The timestamp and user tag of that record are directly copied to this record ( The channel access link can only copy this timestamp ). If the link points to any other field , The value of that field is read and stored in TSE Field , It is then used to get a timestamp .

Field	Summary	Type	DCT	Default	Read	Write	CA PP
ASG	Ask the security team	STRING [29]	Yes		Yes	Yes	No
ASP	Access security Pvt	NOACCESS	No		No	No	No
DISP	Ban putField	UCHAR	No		Yes	Yes	No
DTYP	Device type	DEVICE	Yes		Yes	Yes	No
MLOK	Monitoring lock	NOACCESS	No		No	No	No
MLIS	Monitoring list	NOACCESS	No		No	No	No
PPN	pprocessNotify	NOACCESS	No		No	No	No
PPNR	pprocessNotifyRecord	NOACCESS	No		No	No	No
PUTF	dbPutField The process	UCHAR	No		Yes	No	No
RDES	dbRecordType The address of	NOACCESS	No		No	No	No
RPRO	Reprocess	UCHAR	No		Yes	No	No
TIME	Time	NOACCESS	No		No	No	No
UTAG	Event tags	UINT64	No		Yes	No	No
TSE	Timestamp event	SHORT	Yes		Yes	Yes	No
TSEL	Timestamp link	INLINK	Yes		Yes	Yes	No