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Field Type DCT Initial Access Modify Rec Proc PP
Monitor
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VAL FLOAT No 0 Yes Yes Yes Yes
OUT OUTLINK Yes 0 No No N/A No
RDBL INLINK Yes 0 No No N/A No
DOL INLINK Yes 0 No No N/A No
OMSL GBLCHOICE Yes 0 Yes Yes No No
ACCL FLOAT Yes 0 Yes Yes No No
VELO FLOAT Yes 0 Yes Yes No No
DIST FLOAT Yes 0 Yes Yes No No
IVAL FLOAT Yes 0 Yes Yes No No
MODE RECCHOICE Yes 0 Yes Yes No No
CMOD RECCHOICE Yes 0 Yes Yes No No
IALG RECCHOICE Yes 0 Yes Yes No No
MRES USHORT Yes 0 Yes Yes No No
ERES USHORT Yes 0 Yes Yes No No
PREC SHORT Yes 0 Yes Yes No No
EGU STRING Yes Null Yes Yes No No
DRVH FLOAT Yes 0 Yes Yes No Yes
DRVL FLOAT Yes 0 Yes Yes No Yes
HOPR FLOAT Yes 0 Yes Yes No No
LOPR FLOAT Yes 0 Yes Yes No No
HIHI FLOAT Yes 0 Yes Yes No Yes
LOLO FLOAT Yes 0 Yes Yes No Yes
HIGH FLOAT Yes 0 Yes Yes No Yes
LOW FLOAT Yes 0 Yes Yes No Yes
HHSV GBLCHOICE Yes 0 Yes Yes No Yes
LLSV GBLCHOICE Yes 0 Yes Yes No Yes
HSV GBLCHOICE Yes 0 Yes Yes No Yes
LSV GBLCHOICE Yes 0 Yes Yes No Yes
HLSV GBLCHOICE Yes 0 Yes Yes No Yes
ADEL FLOAT Yes 0 Yes Yes No No
MDEL FLOAT Yes 0 Yes Yes No No
RDBD FLOAT Yes 0 Yes Yes No No
RTRY SHORT Yes 0 Yes Yes No No
STHM SHORT No 0 Yes Yes No Yes
STOP SHORT No 0 Yes Yes No Yes
DMOV SHORT No 0 Yes Yes No No
RVAL LONG No 0 Yes Yes Yes Yes
RBV FLOAT No 0 Yes Yes Yes No
RRBV LONG No 0 Yes Yes Yes No
ALST FLOAT No 0 Yes No No No
MLST FLOAT No 0 Yes No No No
INIT SHORT No 0 Yes Yes No Yes
MCW SHORT No 0 Yes Yes No Yes
MCCW SHORT No 0 Yes Yes No Yes
CW SHORT No 0 Yes Yes No Yes
CCW SHORT No 0 Yes Yes No Yes
DIR SHORT No 0 Yes Yes No Yes
MOVN SHORT No 0 Yes Yes No No
CVEL SHORT No 0 Yes Yes No No
RCNT SHORT No 0 Yes Yes No No
POSM SHORT No 0 Yes Yes No No
LVAL FLOAT No 0 Yes No No No
EPOS FLOAT No 0 Yes Yes No No
MPOS FLOAT No 0 Yes Yes No No
MISS FLOAT No 0 Yes Yes No No
LVEL FLOAT No 0 Yes Yes No No
LACC FLOAT No 0 Yes Yes No No
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Name Summary Description
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VAL Value This is the desired output value, in engineering units. If
DRVH and DRVL are defined, VAL is forced to be within
the drive limits. VAL is either obtained from DOL or set
via dbPuts.
OUT Output Link This field is used by the device support routines to locate
the stepper motor.
RDBL Read Back This link is used to obtain the read back value when a
Location (Input physical read back is attached to the device being driven
link) from the stepper motor.
DOL Desired Output If DOL is a database or channel access link and OMSL is
Location (Input CLOSED_LOOP, then VAL is read from DOL. After the
Link) check for drive limits, VAL will be set to the value
determined by DOL.
OMSL Output Mode Select This field has either the value SUPERVISORY or
CLOSED_LOOP. DOL is used to determine VAL only if
OMSL has the value CLOSED_LOOP. By setting this field,
the record can be switched between supervisory and
closed loop mode of operation. While in closed loop
mode, the VAL field cannot be set via dbPuts.
ACCL Acceleration Number of seconds to reach VELO velocity.
VELO Velocity Rotations per second.
DIST Distance Distance moved by each pulse of the stepper motor.
IVAL Initial Value
MODE Mode Velocity or Position.
CMOD Current Mode Velocity or Position.
IALG Initialization None, Move to positive limit, Move to negative limit.
Algorithm
MRES Motor Pulses per
Revolution
ERES Encoder Pulses per
Revolution
PREC Display Precision Precision with which to display. This field is used by
record support to supply a value when get_precision
is called.
EGU Engineering Units ASCII string describing Engineering units. This field is
used by record support to supply a units description string
when get_units is called.
DRVH Drive High If these values are defined, then VAL will forced to be in
the range DRVL<=VAL<=DRVH
DRVL Drive Low
HOPR High Operating These fields determine the upper and lower display limits
Range for graphics displays and the upper and lower control
limits for control displays. The fields are used by record
support to honor calls to get_graphic_double or
get_control_double.
LOPR Low Operating Range
HIHI Hihi Alarm Limit These fields specify the alarm limits.
HIGH High Alarm Limit
LOW Low Alarm Limit
LOLO Lolo Alarm Limit
HHSV HiHi Alarm Severity These fields specify the alarm severities.
HSV High Alarm Severity
LSV Low Alarm Severity
LLSV LoLo Alarm Severity
HLSV Hardware Limit
Violation Severity
ADEL Archive Deadband These parameters specify hysteresis factors for triggering
monitor callbacks, i.e. monitors specified by calls to
caAddEvent or dbAddEvent. A monitor will not be
triggered until VAL changes by more than the specified
amount.
MDEL Monitor, i.e. value
change, Deadband
RDBD Retry Deadband
RTRY Number Of Retries
Before Failure
STHM Set Home Setting this field to 1 via a dbPut is a command to set
home to the current position of the stepper motor. This
field will automatically be reset to 0 after the command is
accepted.
STOP Stop Setting this field to 1 will cause the motor to stop if it is
moving. This field will automatically be reset to 0 after
the command is accepted.
DMOV Done Moving to
Value
RVAL Raw Data Value RVAL is the value actually sent to the device.
RBV Read Back Value This is the actual read back value obtained from the
hardware itself or from the associated device driver. It is
the responsibility of the device support routine to give this
field a value.
RRBV Raw Read Back Raw read back value obtained from the encoder.
Value
ALST Archive Last Value Value when last monitors for archiver were triggered
These fields are used to implement the hysteresis factors
for monitors.
MLST Monitor Last Value
INIT Initialize
MCW Motor Clockwise
Limit Switch Value
MCCW Motor Counter
Clockwise Limit
Switch Value
CW Is motor clockwise limit switch TRUE?
CCW Is motor counter clockwise limit switch True?
DIR Current Direction
MOVN Is motor moving?
CVEL Has Constant velocity been attained?
RCNT Current Retry
Count
LVAL Last Value
POSM Positive Motion
EPOS Encoder Read
Back Position
MPOS Motor Position
MISS First Attempt Error
LVEL Last Velocity Set
LACC Last Acceleration
Set
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If device support includes init_record, it is called.
If DOL is a constant, then VAL is initialized with its value and UDF is set to FALSE. If DOL is a PV_LINK then a channel access link is created.
init_sm is then called.
upper_alarm_limit = HIHI upper_warning_limit = HIGH lower_warning_limit = LOW lower_alarm_limit = LOLO
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