Readout Gui

NSCL DAQ Software Documentation
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DESCRIPTION

Starts the readout GUI. All of the options on the command line are optional. If they are omitted, the program first attempts to fetch them from the configuration (see the section Configuration files and environment variables below for more information about configuration). If the required information cannot be retrieved from the configuration, dialogs will be launched to prompt for the host and readout path.

The NSCL Data acquisition system uses a specific file directory tree to associate event data and any other data that may be germane to the run. The ReadoutGUI on startup creates this directory structure and enforces it during its operation.

The ReadouGui on startup attempts to launch the readout program specified on the command line, in the configuration or via prompts to the user on the host system specified in the same way. It reports unexpected Readout program exits via a dialog box to the user.

OPTIONS

-host=readout-host

Specifies that readout-host is the name of the computer on which the Readout program should be run. hostname is also used as the data source to which the readout gui connects other pieces of the system it controls, most importantly, the eventlog event data logging program.

-path=readout-program-path

Specifies readout-program-path as the readout program that should be run. The path must be absolute as you cannot make any assumptions about the working directory in which it is resolved. This is an important point that is sometimes missed:

Suppose your current working directory is ~/readout and the Readout program is stored in ~/software/readout/Readout. Specifying the readout program as ../software/readout/Readout will not work as expected.

FILES

Several files are read written to maintain both the static configuration (not changing from run to run) and the last known dynamic configuration (changing from run to run). Every effort is made to preserve state so that if you start the Readout GUI again after it has exited normally or abnomrally, it will return to the state it was when it exited.

~/stagearea/.readoutconfig: Contains state data for both static and dynamic state. This is rewritten as dynamic stat is modified.
.daqconfig: This file is loaded both from the home directory ansd from your current working directory. It allows you to finely tune the startup static state of the readout gui. See CONFIGURATION below for more information about what can be put in this file.
ReadoutCallouts.tcl: This file is loaded from the home directory, the experiment view's current directory and the current working directory. See EXTENSION hooks below for more information about what this file can contain.

CONFIGURATION

The ReadoutGUI has many configuration parameters, although normally the default values are suitable for your use. The program gets configuration from a combination of configuration files, environment variables and default values. See FILES above for the set of configuration files.

The section below describes the configuration parameters, where appropriate the corresponding environment variables and the precedence.

Configuration Parameter: SourceHost

Environment Variable: DAQHOST

Precedence: Command line, Environment variable, config files.

Description: Provides the host in which the readout software is run. This also determines the URL that will be generated to describe to the clients Readout GUI runs where data comes from.

Configuration Parameter: ReadoutPath

Environment Variable: RDOFILE

Precedence: Command line, Environment variable, config files.

Description: Absolute path to the Readout program.

Configuration Parameter: StageArea

Environment Variable: EVENTS

Precedence: Environment, Config File

Description: The root directory of the event data. This normally defaults to ~/stagearea.

Configuration Parameter: Experiment

Environment Variable: EXPDIR

Precedence: Environment, config

Description: The root of the directory where the run data are stored. This defaults to ~/experiment which, if it does not initially exist is linked symbolically to $StageArea/experiment

Configuration Parameter: RunTitle

Environment Variable: EXPTITLE

Precedence: Config File, Environment

Description: Title of the run. This is normally only useful to provide an initial title as it is overidden by any changes the user makes in the GUI.

Configuration Parameter: RunNumber

Environment Variable: N/A

Precedence: Gui, Config file

Description: The run number of the current run if the run is active, or the next run if the run is idle.

Configuration Parameter: ScalerCount

Environment Variable: SCALERS

Precedence: GUI, Configuration file, Environment

Description: Value set to the Readout's scalers variable prior to starting run initialization. This can be, but need not be, used by the Readout program to determine how many scaler channels are expected. Whether and how it is used is entirely up tot he application developer(s).

Configuration Parameter: ScalerInterval

Environment Variable: SCALERINTERVAL

Precedence: Gui, Config file, Environment

Description: Determines the value set in the Readout program's frequency variable prior to run initiaization. This can be but need not be used to set the period of the scaler readout trigger. Whether and how it is used is entirely up to the application developer(s).

Configuration Parameter: Recording

Environment Variable: N/A

Precedence: GUI, Config file

Description: If the run is active,this non zero when event data are being recorded. When the run is not active, this variable reflects whether or not the next run will record event data.

Configuration Parameter: Timed

Environment Variable: N/A

Precedence: Gui, Config file

Description: Reflects whether or not this run (or the next run if idle) will be a timed run

Configuration Parameter: TimedLength

Environment Variable: N/A

Precedence: Gui, Config file

Description: If the configuration/state parameter Timed is true, this variable is the number of seconds for which a timed run should take data.

EXTENSION HOOKS

The Readout GUI can be extended by user supplied scripts. How to provide an extension script is described in FILES under the description of ReadoutCallouts.tcl. This section describes the callbacks ReadoutGUI makes to any extension that defines them and the API available to those scripts (see Programmatic Inteface below).

In addition to executing arbitrary Tcl code at the global level when it is loaded, ReadoutCallouts.tcl can provide procs that are called at well defined points in the execution of the Readout GUI.

The callbacks the set of ReadoutCallouts can provide are:

OnStart: Called when the readout program is started up. At the time this is called, the Readout program may not be sufficiently initialized to accept commands. if your script feeds commands you might want to insert a short delay prior to doing this.
OnBegin: This proc is called just after the run has been started. It is passed the run number of the run that has just started. By the time OnBegin is called, the Event Logging program (if recording is enabled) is ready to run. The Readout program has not yet, however, been told to start the run.
OnEnd: Called just after a run has ended. The Readout program has been asked to end however it is not known yet that the readout program has actually sent its end of run buffer to the event distribution system.
OnPause: Called when a data taking run is being paused. This is called at an analagous time to the OnEnd call.
OnResume: Called when a data taking run is being resumed. This is called at an analgous time to the OnBegin function.

Programmatic Interface

Readout GUI extension scripts can also interact with well defined interfaces to the Readout GUI. This section describes those interfaces.

The Readout GUI is segmented into several packages. Each package is implemented as a Tcl package and you should use package require to ensure the package is loaded prior to invoking procs from the package.

ReadoutState: Provides the ability to manipulate and inquire about the state of the system.
ReadoutControl: Provides the ability to control the readout program.
ReadoutGui: Provides the ability to do things that the GUI elements can cause to happen.
ReadougGUIPanel: Provides access to the gui elements of the user interface itself. Note the first g in this package name is not a typo.

Programmatic interface

ReadoutState package

The ReadoutState package manipulates and gets access to various state values of the Readout GUI. These commands are located in the ReadoutState namespace. If you don't want to qualify calls with ReadoutState::, you can namespace import ReadoutState::*. The descriptions below assume this has been done.

setTitle newTitle: Sets the title string for the next run. Unlike the GUI, which does not allow title string changes until the run is halted, the software can change this string at any time and the new value will be reflected in the GUI. The Readout program, however, only receives a new title string just prior to the start of a run, and prior to the call to OnBegin.
setRun runNumber: Sets the run number for the next run that Readout will start. See setTitle for for what this means and when the Readout program will actually see this setting.
getRun: Returns the run number
incRun: Increments the run number held by the GUI.
setScalerCount scalers: Sets the number of scalers the user wants read out. This is updated in the readout program at the start of the next run. It is possible for the readout software to override this value programmtically. It is intended for scaler readout software that knows how to use this value to adjust the set of scalers that are actually being read.
getScalerCount: Returns the proposed number of scalers
setScalerPeriod timInSeconds: Sets the number of seconds between timed scaler readout in seconds. Note that it is up to the application code to select a timed trigger and to modify the time interval based on this value at the beginning of each run. The value will be pushed into the main interpreter's frequency variable.
getScalerPeriod: Returns the number of seconds between periodic scaler readouts.
getRecording: Returns true if event recording is enabled.
enableRecording: Enables event recording. As with all of these parameters, event recording determines what happens at the start of the next run.
disableRecording: Disable event recording.
isTimedRun: Returns a true boolean value if the Timed run checkbox is enabled.
TimedRun: Enables the next run to be a timed run.
notTimedRun: Says that the next run will not be a timed run.
timedLength: Returns the length of a timed run. The length is returned as the number of seconds the run would last.
setTimedLength seconds: Sets the length of the timed run in seconds. You must also enabled timed running in order for this to mean anything.

Programmatic interface

ReadoutControl package

This package allows you to set and inquire the known state of the Readout program. You can us it to send arbitrary messages to the readout program or to perform specific state transitions of the run.

Where you force a state change in the Readout program that the GUI normally forces (e.g. starting a run), it is important that you use the higher level functions to do that so that the GUI remains consistent with the state of the Readout. If, for example, you start a run by sending the begin command directly to the Readout program, the run control buttons will not reflect that the run can be halted. Use of e.g. ReadoutControl::Begin maintains the state correspondence.

All of the procs described in this section are in the ReadoutControl namespace. If you don't want to prefix each command with ::ReadoutControl:: you should import the namespace using namespace import ::ReadoutControl::*.

getReadoutState

Returns the known state of the readout program. This can be any of the following textual values:

NotLoaded: The Readout program is not running. Either it was never started, or it failed.
NotRunning: The Readout program is present, but the run is in the halted state.
Paused: The readout program has an active run that is currently paused.
Active: The readout program has an active run and is taking data.

isExecuting

Returns a true boolean value if the Readout program is executing. That is if ReadoutControl::getReadoutState would not return NotLoaded

SendCommand string

Sends a literalcommand to the readout program. In the case of the SBS Readout skeleton you might use this in e.g. OnStart to force the readout program to source some configuration script.

SetReadoutProgram host path

Determines which readout program will be run next, and on which system. host specifies the target processor, and path should be the full absolute path to the program. If you have a relative path you can use the Tcl file normalize command to turn it into an absolute path.

ExitReadoutProgram

Forces the readout program to exit. T his is done as follows:

The end command is sent to the program.
The exit command is sent to the program.
The pipe open to the readout program is closed.

StartReadoutProgram

Starts the readout program using the current target host and path. If the readout program is running it is stopped. This means that to programmatically change readout programs you can do something like this:

package require ReadoutControl

set newProgram ~/daq/Readout/Readout
set host       spdaq22
ReadoutControl::SetReadoutProgram $host [file normalize $newProgram]
ReadoutControl::StartReadoutProgram

SetRun runNumber

Sends a command to the readout program to set the run number to number. You should normally use the functions in the package ReadoutState to do this, in order to maintain synchronization between the GUI and the Readout program state.

If the ReadoutGui believes the readout program is in the NotRunning state, an error will be thrown.

SetTitle newTitleString

Sends a message to the readout program to change its title. You should normally use the functions in the package ReadoutState to do this, in order to maintain synchronization between the GUI and the Readout program state.

If the ReadoutGui believes the readout program is not in the NotRunning state, an error will be thrown.

Begin

Sends a message to the readout software to start a run. You should normally use the functions in the package ReadoutState to do this, in order to maintain synchronization between the GUI and the Readout program state.

If the ReadoutGui believes the readout program is not in the NotRunning state, an error will be thrown.

End

Sends a message to the readout software ending any active run. You should normally use the functions in the package ReadoutState to do this, in order to maintain synchronization between the GUI and the Readout program state.

If the ReadoutGui believes the readout program is in the NotRunning state, an error will be thrown.

Pause

Pauses any active run. You should normally use the functions in the package ReadoutState to do this, in order to maintain synchronization between the GUI and the Readout program state.

If the ReadoutGui believes the readout program is not in the Active state, an error will be thrown.

Resume

Sends a message to the readout software to resume a paused run. You should normally use the functions in the package ReadoutState to do this, in order to maintain synchronization between the GUI and the Readout program state.

If the ReadoutGui believes the readout program is not in the Paused state, an error will be thrown.

Programmatic interface

ReadoutGUI package

This package provides access to the functions that the graphical user interface itself calls in response to button pushes. Often using these methods is the safest way to do something as gthen you are duplicating the action of the GUI elements.

All procs described here are in the ReadoutGui:: namespace. If you don't want to have to precede each function name with ::ReadoutGUI, use namespace import ::ReadoutGui::*

Start

Simulates the File→Start menu selection. The Readout program selected is started on the target host without any attempt to stop any existing Readout.

Restart

Simulates the File→ Restart menu choice. This attempts to stop an existing Readout program before starting a new instance of the selected Readout program in the target host.

Begin

Simulates a press of the Begin button. This attempts to start a run. Note that programmatically, there are no protections at this level against beginning a run that is already running. You should inquire the state of the system prior to attempting to start a run. For example:


if {[ReadoutControl::getReadoutState] eq "NotRunning"} {
   ReadoutGui::Begin
} else {
   # Here recover from the fact that the run
   # Cannot be started at this point in time.
}

Pause

Simulates a press of the Pause button. as for Begin the state should be checked to ensure it is Active before invoking this.

Resume

Simulates a click of the Resume button. Call getState to ensure the state is Paused before invoking this.

End

Simulates a click of the End button. As before, ensure this is legal by comparing the return value of getState to either Paused or Active> (paused runs can be ended without resumption.

Programmatic interface

Controllling the GUI

The ReadougGUIPanel package provides access to the graphical user interfaces that make up the readout gui. YOu can use this to modify the state of existing widgets as well as to add new widges of your own to the GUI.

All functions in this section are in the namespace ReadougGUIPanel. To avoid needing to qualify each reference you can: namespace import ::ReadougGUIPanel::*.

addUserMenu ident label

Allows you to add a user menu to the menubar of the GUI. The ident parameter is used as the last element of the menu widget path. label is the text string that will label the element.

The actual full widget path of the menu created is returned. You can use this path to modify the menu configuration or to add elements to the menu.

addUserFrame ident

Adds a frame to the bottom of the panel (you can add as many user frames as you want). By frame we mean a Tk frame widget. ident is the last element of the frame's widget path. The full path will be returned.

At this time, the frame will span the width of the Readout GUI toplevel widget. Once you have created this frame you can stock it with whatever widgets you want. The example below is a bit silly.


set frame [ReadougGUIPanel::addUserFrame myframe]
button $frame.beep -text Beep -command {puts beep}
button $frame.bop  -text Bop  -command {puts bop}
button $frame.beebop -text BeeBop -command {puts "Now that's rockin'"}
grid $frame.beep $frame.bop
grid $frame.beebop

getHost

Returns the host in which the readout program will be, or is running

getPath

Returns the path to the readout program that will be, or is running in the target host.

setTitle newTitle

Sets the title string in the ReadoutGUI widget to newTitle. If a run is started via the GUI, newTitle will be the title of that run.

getTitle

Returns the contents of the title widget in the GUI. Unless manually, or programmatically modified, this is the title of the next or current run.

getRunNumber

Returns the contents of the run number widget.

setRun newRunNumber

Sets the run number widget contents to newRunNumber this will be the run number for the next run.

incrRun

Increments the run number (adds one to it).

setHost hostname

Sets the target host for the readout program to hostname. The next time the readout program is started, it will be run in hostname

setPath path

Sets a new readout program to path. It is safest if this is the full path to the program or script to run. The file normalize command can be used to turn relative paths into absolute paths. For example:


set absolutePath [file normalize ../Readout]
ReadougGUIPanel::setPath $absolutePath

recordOff

Turns off the Record checkbutton. Unless modified, the next run will not be recorded to disk.

recordOn

Turns on the Record checkbutton. Unless modified, the next run will be recorded to disk.

setScalers channels period

Sets the hint of the number of scalers and the scaler readout period. Unless modified, these parameter are fed to the readout program at the start of the next run. period is the integer number of seconds between scaler trigger. channels is the number of channels requested.

Note that in the SBS readout framework it is up to application specific code to do something with these numbers. The VM-USB and CC-USB frameworks configure the scaler readout period in the configuration file when setting up the scaler stack.

getScalers

Returns a two element list containing the ReadoutGui's understanding of the number of scalers to be read and the interval in seconds between scaler readouts.

Once again these numbers could be completely meaningless depending on the use made of them by specific readout frameworks and any application specific code that may be grafted into those frameworks.

recordData

Returns a true value if the Record checkbutton is checked.

outputText text

Appends text to the GUI's text window. This window contains the output from the readout program as well as anything else put there via this call.

isTimed

Returns a true value if the Timed Run check box is checked.

setTimed state

Sets the Timed Run check button to state. This governs whether or not the next run is a timed run.

getRequestedRunTime

Returns the length of a timed run if the Timed Run were set at the start of the run. The time is returned in seconds

setRequestedRunTime seconds

Sets the desired timed run duration to seconds. This does not modify the state of the Timed Run check button however.

EXAMPLE

The toy extension below logs state transitions and Readout startups to file.

Example 1. Logging extension to readout gui


set filename [file join ~ readout.log]

proc logToFile message {
   global filename
   
   set fd [open $filename "w+"]
   set timestamp [clock format [clock seconds]]
   puts $fd "$timestamp : $message"
   close $fd
}
proc OnBegin run {
   logToFile "Run $run Begun"
}
proc OnEnd run {
   logToFile "Run $run has ended"
}
proc OnPause run {
   logToFile "Run $run has been paused"
}
proc OnResume run {
   logToFile "Run $run has been resumed"
}
proc OnStart {} {
   logToFile "Readout program has been started"
}

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Readout Gui

Name

Synopsis

DESCRIPTION

OPTIONS

FILES

CONFIGURATION

EXTENSION HOOKS

Programmatic Interface

Programmatic interface

Programmatic interface

Programmatic interface

Programmatic interface

EXAMPLE