#*************************************************************************
# Copyright (c) 2002 The University of Chicago, as Operator of Argonne
#     National Laboratory.
# Copyright (c) 2002 The Regents of the University of California, as
#     Operator of Los Alamos National Laboratory.
# EPICS BASE is distributed subject to a Software License Agreement found
# in file LICENSE that is included with this distribution.
#*************************************************************************

=title Data Fanout Record (dfanout)

The Data Fanout or "dfanout" record is used to forward data to up to
eight other records. It's similar to the fanout record except that the
capability to forward data has been added to it. If has no associated
device support.

=head2 Parameter Fields

The fields in this record can be classified into the following categories:

=over

=item *
scan parameters

=item *
desired output parameters

=item *
write parameters

=item *
operator display parameters

=item *
alarm parameters

=item *
monitor parameters

=item *
run-time and simulation mode parameters

=back

=recordtype dfanout

=cut

menu(dfanoutSELM) {
	choice(dfanoutSELM_All,"All")
	choice(dfanoutSELM_Specified,"Specified")
	choice(dfanoutSELM_Mask,"Mask")
}

recordtype(dfanout) {

=head3 Scan Parameters

The data fanout record has the standard fields for specifying under what
circumstances it will be processed. These fields are listed in
L<Scan Fields>. In addition, L<Scanning Specification> explains how these
fields are used. Since the data fanout record supports no direct interfaces
to hardware, it cannot be scanned on I/O interrupt, so its SCAN field
cannot be C<I/O Intr>.

=head3 Desired Output Parameters

The data fanout record must specify where the desired output value
originates, i.e., the data which is to be fowarded to the records in its
output links. The output mode select (OMSL) field determines whether the
output originates from another record or from run-time database access.
When set to C<closed_loop>, the desired output is retrieved from the link
specified in the desired output (DOL) field, which can specify either a
database or a channel access link, and placed into the VAL field. When set
to C<supervisory>, the desired output can be written to the VAL field via
dbPuts at run-time.

The DOL field can also be a constant in which case the VAL field is
initialized to the constant value.

Note that there are no conversion parameters, so the desired output value
undergoes no conversions before it is sent out to the output links.

=fields DOL, OMSL, VAL

=head3 Write Parameters

The OUTA-OUTH fields specify where VAL is to be sent. Each field that is to
forward data must specify an address to another record. See 
L<Address Specification> for information on specifying links.

The SELL, SELM, and SELN fields specify which output links are to be
used.

=head4 Menu dfanoutSELM

SELM is a menu, with three choices:

=menu dfanoutSELM

If SELM=="All", then all output links are used, and the values of
SELL and SELN are ignored.

If SELM=="Specified", then the value of SELN is used to specify a single
link which will be used. If SELN==0, then no link will be used; if SELN==1,
then OUTA will be used, and so on.

SELN can either have its value set directly, or have its values retrieved
from another EPICS PV. If SELL is a valid PV link, then SELN will be set to
the values of the linked PV.

If SELM=="Mask", then SELN will be treated as a bit mask. If bit one of
SELN is set, then OUTA will be used, if bit two is set, OUTB will be used.
Thus if SELN==5, OUTC and OUTA will be used.

=fields OUTA, OUTB, OUTC, OUTD, OUTE, OUTF, OUTG, OUTH

=head3 Operator Display Parameters

These parameters are used to present meaningful data to the operator. They
display the value and other parameters of the data fanout record either
textually or graphically.

The EGU field can contain a string of up to 16 characters describing the
value on the VAL field.

The HOPR and LOPR fields determine the upper and lower display limits for
graphic displays and the upper and lower control limits for control
displays. They apply to the VAL, HIHI, HIGH, LOW, and LOLO fields. The
record support routines C<get_graphic_double()> and C<get_control_double()>
retrieve HOPR and LOPR.

See L<Fields Common to All Record Types> for more on the record name (NAME)
and description (DESC) fields.

=fields EGU, HOPR, LOPR, NAME, DESC

=head3 Alarm Parameters

The possible alarm conditions for data fanouts are the SCAN, READ, INVALID,
and limit alarms. The SCAN and READ alarms are called by the record
routines. The limit alarms are configured by the user in the HIHI, LOLO,
HIGH, and LOW fields using floating point values. The limit alarms apply 
only to the VAL field. The severity for each of these limits is specified
in the corresponding field (HHSV, LLSV, HSV, LSV) and can be either
NO_ALARM, MINOR, or MAJOR. In the hysteresis field (HYST) can be entered a
number which serves as the deadband on the limit alarms.

See L<Alarm Specification> for a complete explanation of alarms and these
fields. L<Alarm Fields> lists other fields related to alarms that are
common to all record types.

=fields HIHI, HIGH, LOW, LOLO, HHSV, HSV, LSV, LLSV, HYST

=head3 Monitor Parameters

These parameters are used to determine when to send monitors placed on the
VAL field. These monitors are sent when the value field exceeds the last
monitored fields by the specified deadband, ADEL for archivers monitors and
MDEL for all other types of monitors. If these fields have a value of zero,
everytime the value changes, a monitor will be triggered; if they have a
value of -1, everytime the record is scanned, monitors are triggered. See
L<Monitor Specification> for a complete explanation of monitors.

=fields ADEL, MDEL

=head3 Run-Time Parameters and Simulation Mode Parameters

These parameters are used by the run-time code for processing the data
fanout record. Ther are not configurable. They are used to implement the
hysteresis factors for monitor callbacks.

=fields LALM, ALST, MLST

=cut

	include "dbCommon.dbd" 
	field(VAL,DBF_DOUBLE) {
		prompt("Desired Output")
		promptgroup("40 - Input")
		asl(ASL0)
		pp(TRUE)
	}
	field(SELM,DBF_MENU) {
		prompt("Select Mechanism")
		promptgroup("30 - Action")
		interest(1)
		menu(dfanoutSELM)
	}
	field(SELN,DBF_USHORT) {
		prompt("Link Selection")
		interest(1)
		initial("1")
	}
	field(SELL,DBF_INLINK) {
		prompt("Link Selection Loc")
		promptgroup("30 - Action")
		interest(1)
	}
	field(OUTA,DBF_OUTLINK) {
		prompt("Output Spec A")
		promptgroup("50 - Output")
		interest(1)
	}
	field(OUTB,DBF_OUTLINK) {
		prompt("Output Spec B")
		promptgroup("50 - Output")
		interest(1)
	}
	field(OUTC,DBF_OUTLINK) {
		prompt("Output Spec C")
		promptgroup("50 - Output")
		interest(1)
	}
	field(OUTD,DBF_OUTLINK) {
		prompt("Output Spec D")
		promptgroup("50 - Output")
		interest(1)
	}
	field(OUTE,DBF_OUTLINK) {
		prompt("Output Spec E")
		promptgroup("50 - Output")
		interest(1)
	}
	field(OUTF,DBF_OUTLINK) {
		prompt("Output Spec F")
		promptgroup("50 - Output")
		interest(1)
	}
	field(OUTG,DBF_OUTLINK) {
		prompt("Output Spec G")
		promptgroup("50 - Output")
		interest(1)
	}
	field(OUTH,DBF_OUTLINK) {
		prompt("Output Spec H")
		promptgroup("50 - Output")
		interest(1)
	}
	field(DOL,DBF_INLINK) {
		prompt("Desired Output Loc")
		promptgroup("40 - Input")
		interest(1)
	}
	field(OMSL,DBF_MENU) {
		prompt("Output Mode Select")
		promptgroup("50 - Output")
		interest(1)
		menu(menuOmsl)
	}
	field(EGU,DBF_STRING) {
		prompt("Engineering Units")
		promptgroup("80 - Display")
		interest(1)
		size(16)
		prop(YES)
	}
	field(PREC,DBF_SHORT) {
		prompt("Display Precision")
		promptgroup("80 - Display")
		interest(1)
		prop(YES)
	}
	field(HOPR,DBF_DOUBLE) {
		prompt("High Operating Range")
		promptgroup("80 - Display")
		interest(1)
		prop(YES)
	}
	field(LOPR,DBF_DOUBLE) {
		prompt("Low Operating Range")
		promptgroup("80 - Display")
		interest(1)
		prop(YES)
	}
	field(HIHI,DBF_DOUBLE) {
		prompt("Hihi Alarm Limit")
		promptgroup("70 - Alarm")
		pp(TRUE)
		interest(1)
		prop(YES)
	}
	field(LOLO,DBF_DOUBLE) {
		prompt("Lolo Alarm Limit")
		promptgroup("70 - Alarm")
		pp(TRUE)
		interest(1)
		prop(YES)
	}
	field(HIGH,DBF_DOUBLE) {
		prompt("High Alarm Limit")
		promptgroup("70 - Alarm")
		pp(TRUE)
		interest(1)
		prop(YES)
	}
	field(LOW,DBF_DOUBLE) {
		prompt("Low Alarm Limit")
		promptgroup("70 - Alarm")
		pp(TRUE)
		interest(1)
		prop(YES)
	}
	field(HHSV,DBF_MENU) {
		prompt("Hihi Severity")
		promptgroup("70 - Alarm")
		pp(TRUE)
		interest(1)
		prop(YES)
		menu(menuAlarmSevr)
	}
	field(LLSV,DBF_MENU) {
		prompt("Lolo Severity")
		promptgroup("70 - Alarm")
		pp(TRUE)
		interest(1)
		prop(YES)
		menu(menuAlarmSevr)
	}
	field(HSV,DBF_MENU) {
		prompt("High Severity")
		promptgroup("70 - Alarm")
		pp(TRUE)
		interest(1)
		prop(YES)
		menu(menuAlarmSevr)
	}
	field(LSV,DBF_MENU) {
		prompt("Low Severity")
		promptgroup("70 - Alarm")
		pp(TRUE)
		interest(1)
		prop(YES)
		menu(menuAlarmSevr)
	}
	field(HYST,DBF_DOUBLE) {
		prompt("Alarm Deadband")
		promptgroup("70 - Alarm")
		interest(1)
	}
	field(ADEL,DBF_DOUBLE) {
		prompt("Archive Deadband")
		promptgroup("80 - Display")
		interest(1)
	}
	field(MDEL,DBF_DOUBLE) {
		prompt("Monitor Deadband")
		promptgroup("80 - Display")
		interest(1)
	}
	field(LALM,DBF_DOUBLE) {
		prompt("Last Value Alarmed")
		special(SPC_NOMOD)
		interest(3)
	}
	field(ALST,DBF_DOUBLE) {
		prompt("Last Value Archived")
		special(SPC_NOMOD)
		interest(3)
	}
	field(MLST,DBF_DOUBLE) {
		prompt("Last Val Monitored")
		special(SPC_NOMOD)
		interest(3)
	}

=head2 Record Support

=head3 Record Support Routines

=head2 C<init_record()>

This routine initializes all output links that are defined. Then it initializes
DOL if DOL is a constant or a PV_LINK. When initializing the output links
and the DOL link, a non-zero value is returned if an error occurs.

=head2 C<process()>

See next section.

=head2 C<get_units()>

The routine copies the string specified in the EGU field to the location
specified by a pointer which is passed to the routine.

=head2 C<get_graphic_double()>

If the referenced field is VAL, HIHI, HIGH, LOW, or LOLO, this routine sets
the C<upper_disp_limit> member of the C<dbr_grDouble> structure to the
HOPR and the C<lower_disp_limit> member to the LOPR. If the referenced
field is not one of the above fields, then C<recGblGetControlDouble()>
routine is called.

=head2 C<get_control_double()>

Same as the C<get_graphic_double()> routine except that it uses the
C<dbr_ctrlDouble> structure.

=head2 C<get_alarm_double()>

This sets the members of the C<dbr_alDouble> structure to the specified
alarm limits when the referenced field is VAL:

=over

upper_alarm_limit = HIHI

upper_warning_limit = HIGH

lower_warning_limit = LOW

lower_alarm_limit = LOLO

=back

If the referenced field is not VAL, the C<recGblGetAlarmDouble()> routine
is called.

=head3 Record Processing

=over

=item 1.
The C<process()> routine first checks that DOL is not a constant link and
that OMSL is set to "closed_loop". If so, it retrieves a value through DOL
and places it into VAL. If no errors occur, UDF is set to FALSE.

=item 2.
PACT is set TRUE, and the record's timestamp is set.

=item 3.
A value is fetched from SELL and placed into SELN.

=item 4.
Alarms ranges are checked against the contents of the VAL field.

=item 5.
VAL is then sent through the OUTA-OUTH links by calling C<dbPutLink()> for
each link, conditional on the setting of SELM and the value in SELN.

=item 6.
Value and archive monitors are posted on the VAL field if appropriate based on
the settings of MDEL and ADEL respectively.

=item 7.
The data fanout's forward link FLNK is processed.

=item 6.
PACT is set FALSE, and the C<process()> routine returns.

=back

=cut
}
