Hi, our logger was running. I have tried restarting mlogger (even though we haven't
changed variable names). We ran the following commands one after another and still no
luck with history plot. Is there anything else that could be causing these problems?

Kind regards,
Hassan 

==================================================================================

[lm17773@it038146 ~]$ cd /opt/midas_software/midas/bin/
[lm17773@it038146 bin]$ mhttpd
[mhttpd,ERROR] [odb.cxx:1646:db_open_database,ERROR] Removed ODB client 'mhttpd',
index 0 because process pid 20094 does not exists
[mhttpd,ERROR] [odb.cxx:1646:db_open_database,ERROR] Removed ODB client 'Logger',
index 1 because process pid 20214 does not exists
[mhttpd,INFO] Removed open record flag from "/Experiment/Security/RPC hosts/Allowed hosts"
[mhttpd,INFO] Removed exclusive access mode from "/Experiment/Security/RPC
hosts/Allowed hosts"
[mhttpd,INFO] Removed open record flag from "/Experiment/Security/mhttpd hosts/Allowed
hosts"
[mhttpd,INFO] Removed exclusive access mode from "/Experiment/Security/mhttpd
hosts/Allowed hosts"
[mhttpd,INFO] Removed open record flag from "/Logger/History"
[mhttpd,INFO] Removed exclusive access mode from "/Logger/History"
[mhttpd,INFO] Removed open record flag from "/Sequencer/State"
[mhttpd,INFO] Removed exclusive access mode from "/Sequencer/State"
[mhttpd,INFO] Removed open record flag from "/History/LoggerHistoryChannel"
[mhttpd,INFO] Removed exclusive access mode from "/History/LoggerHistoryChannel"
[mhttpd,INFO] Removed open record flag from "/Equipment/slow/Variables"
[mhttpd,INFO] Removed exclusive access mode from "/Equipment/slow/Variables"
[mhttpd,INFO] Removed open record flag from "/Equipment/Trigger/Statistics/Events per
sec."
[mhttpd,INFO] Removed exclusive access mode from "/Equipment/Trigger/Statistics/Events
per sec."
[mhttpd,INFO] Removed open record flag from "/Equipment/Trigger/Statistics/kBytes per
sec."
[mhttpd,INFO] Removed exclusive access mode from "/Equipment/Trigger/Statistics/kBytes
per sec."
[mhttpd,INFO] Removed open record flag from "/Equipment/Periodic/Variables"
[mhttpd,INFO] Removed exclusive access mode from "/Equipment/Periodic/Variables"
[mhttpd,INFO] Removed open record flag from "/Equipment/Scaler/Variables"
[mhttpd,INFO] Removed exclusive access mode from "/Equipment/Scaler/Variables"
[mhttpd,INFO] Corrected 10 ODB entries
[mhttpd,INFO] Deleted entry '/System/Clients/20094' for client 'mhttpd' because it is
not connected to ODB
Mongoose web server will use SSL certificate file "/home/lm17773/online/ssl_cert.pem"
Mongoose web server will use authentication realm "sampleexpt", password file
"/home/lm17773/online/htpasswd.txt"
mongoose web server is redirecting HTTP port 8080 to
https://it038146.users.bris.ac.uk:8443
mongoose web server is listening on the HTTP port 8080
mongoose web server is listening on the HTTPS port 8443
====================================================================================

[lm17773@it038146 bin]$ mlogger
[Logger,INFO] Deleted entry '/System/Clients/20214' for client 'Logger' because it is
not connected to ODB
Log     directory is /home/lm17773/online/
Data    directory is same as Log unless specified in /Logger/channels/
History directory is same as Log unless specified in /Logger/history/
ELog    directory is same as Log
SQL     database is localhost/sampleexpt/Runlog
MIDAS logger started. Stop with "!"
====================================================================================
[lm17773@it038146 bin]$ fetest
Frontend name          :     fetest
Event buffer size      :     10485760
User max event size    :     4194304
User max frag. size    :     4194304
# of events per buffer :     2

Connect to experiment sampleexpt...
OK
Init hardware...frontend_init!
Event size set to 10240 bytes
Ring buffer wait sleep 1 ms
OK
time 1564131394, data 97.814758
time 1564131395, data 96.592583
time 1564131396, data 95.105652
time 1564131397, data 93.358040
time 1564131398, data 91.354546
time 1564131399, data 89.100655
time 1564131400, data 86.602539
time 1564131401, data 83.867058
time 1564131402, data 80.901703
time 1564131403, data 77.714592
Warning: bank RND4 has zero size
time 1564131404, data 74.314484
time 1564131405, data 70.710678
time 1564131406, data 66.913063
time 1564131407, data 62.932041
====================================================================================






> > Hi,
> > 
> > We've been trying to run Fetest in the attempt of plotting the sine wave data on
> > the history page on the web server. However each time we've tried running a new
> > plot we have come across the error of 'no data' from the variables. In the
> > status page we are clearly obtaining data from the frontend and it is updating
> > the variable as expected in SLOW.
> > 
> > When setting up MIDAS we managed to produce a history plot from Fetest but are
> > unable to do so any longer. We did have a go at modifying the Fetest code but
> > created a backup before doing so and are now running the original backup.
> > 
> > What could be causing the Fetest data not to be showing in the history plot?
> 
> Is the logger running? (this application is handling the history data).
> If yes: Did you change the variable names? If yes: restart the logger.

> Hi, our logger was running.


One more thing is to check that the history files are actually being written to. Be default
the history files are written into the same directory where you have ODB, etc and
the file names are "*.hst".

Second thing, you can run "mlogger -v" and it will report that it is writing history events
into the history.

If all these things are happening,

Third, you can run "mhist" to see the data directly from the data files.

If all of these work, but you still get nothing in mhttpd, that would be very strange. If I remember
right, to see the sine wave, the history variable to plot is equipment "slow", variable "slow".


K.O.



> I have tried restarting mlogger (even though we haven't
> changed variable names). We ran the following commands one after another and still no
> luck with history plot. Is there anything else that could be causing these problems?
> 
> Kind regards,
> Hassan 
> 
> ==================================================================================
> 
> [lm17773@it038146 ~]$ cd /opt/midas_software/midas/bin/
> [lm17773@it038146 bin]$ mhttpd
> [mhttpd,ERROR] [odb.cxx:1646:db_open_database,ERROR] Removed ODB client 'mhttpd',
> index 0 because process pid 20094 does not exists
> [mhttpd,ERROR] [odb.cxx:1646:db_open_database,ERROR] Removed ODB client 'Logger',
> index 1 because process pid 20214 does not exists
> [mhttpd,INFO] Removed open record flag from "/Experiment/Security/RPC hosts/Allowed hosts"
> [mhttpd,INFO] Removed exclusive access mode from "/Experiment/Security/RPC
> hosts/Allowed hosts"
> [mhttpd,INFO] Removed open record flag from "/Experiment/Security/mhttpd hosts/Allowed
> hosts"
> [mhttpd,INFO] Removed exclusive access mode from "/Experiment/Security/mhttpd
> hosts/Allowed hosts"
> [mhttpd,INFO] Removed open record flag from "/Logger/History"
> [mhttpd,INFO] Removed exclusive access mode from "/Logger/History"
> [mhttpd,INFO] Removed open record flag from "/Sequencer/State"
> [mhttpd,INFO] Removed exclusive access mode from "/Sequencer/State"
> [mhttpd,INFO] Removed open record flag from "/History/LoggerHistoryChannel"
> [mhttpd,INFO] Removed exclusive access mode from "/History/LoggerHistoryChannel"
> [mhttpd,INFO] Removed open record flag from "/Equipment/slow/Variables"
> [mhttpd,INFO] Removed exclusive access mode from "/Equipment/slow/Variables"
> [mhttpd,INFO] Removed open record flag from "/Equipment/Trigger/Statistics/Events per
> sec."
> [mhttpd,INFO] Removed exclusive access mode from "/Equipment/Trigger/Statistics/Events
> per sec."
> [mhttpd,INFO] Removed open record flag from "/Equipment/Trigger/Statistics/kBytes per
> sec."
> [mhttpd,INFO] Removed exclusive access mode from "/Equipment/Trigger/Statistics/kBytes
> per sec."
> [mhttpd,INFO] Removed open record flag from "/Equipment/Periodic/Variables"
> [mhttpd,INFO] Removed exclusive access mode from "/Equipment/Periodic/Variables"
> [mhttpd,INFO] Removed open record flag from "/Equipment/Scaler/Variables"
> [mhttpd,INFO] Removed exclusive access mode from "/Equipment/Scaler/Variables"
> [mhttpd,INFO] Corrected 10 ODB entries
> [mhttpd,INFO] Deleted entry '/System/Clients/20094' for client 'mhttpd' because it is
> not connected to ODB
> Mongoose web server will use SSL certificate file "/home/lm17773/online/ssl_cert.pem"
> Mongoose web server will use authentication realm "sampleexpt", password file
> "/home/lm17773/online/htpasswd.txt"
> mongoose web server is redirecting HTTP port 8080 to
> https://it038146.users.bris.ac.uk:8443
> mongoose web server is listening on the HTTP port 8080
> mongoose web server is listening on the HTTPS port 8443
> 
====================================================================================
> 
> [lm17773@it038146 bin]$ mlogger
> [Logger,INFO] Deleted entry '/System/Clients/20214' for client 'Logger' because it is
> not connected to ODB
> Log     directory is /home/lm17773/online/
> Data    directory is same as Log unless specified in /Logger/channels/
> History directory is same as Log unless specified in /Logger/history/
> ELog    directory is same as Log
> SQL     database is localhost/sampleexpt/Runlog
> MIDAS logger started. Stop with "!"
> 
====================================================================================
> [lm17773@it038146 bin]$ fetest
> Frontend name          :     fetest
> Event buffer size      :     10485760
> User max event size    :     4194304
> User max frag. size    :     4194304
> # of events per buffer :     2
> 
> Connect to experiment sampleexpt...
> OK
> Init hardware...frontend_init!
> Event size set to 10240 bytes
> Ring buffer wait sleep 1 ms
> OK
> time 1564131394, data 97.814758
> time 1564131395, data 96.592583
> time 1564131396, data 95.105652
> time 1564131397, data 93.358040
> time 1564131398, data 91.354546
> time 1564131399, data 89.100655
> time 1564131400, data 86.602539
> time 1564131401, data 83.867058
> time 1564131402, data 80.901703
> time 1564131403, data 77.714592
> Warning: bank RND4 has zero size
> time 1564131404, data 74.314484
> time 1564131405, data 70.710678
> time 1564131406, data 66.913063
> time 1564131407, data 62.932041
> 
====================================================================================
> 
> 
> 
> 
> 
> 
> > > Hi,
> > > 
> > > We've been trying to run Fetest in the attempt of plotting the sine wave data on
> > > the history page on the web server. However each time we've tried running a new
> > > plot we have come across the error of 'no data' from the variables. In the
> > > status page we are clearly obtaining data from the frontend and it is updating
> > > the variable as expected in SLOW.
> > > 
> > > When setting up MIDAS we managed to produce a history plot from Fetest but are
> > > unable to do so any longer. We did have a go at modifying the Fetest code but
> > > created a backup before doing so and are now running the original backup.
> > > 
> > > What could be causing the Fetest data not to be showing in the history plot?
> > 
> > Is the logger running? (this application is handling the history data).
> > If yes: Did you change the variable names? If yes: restart the logger.

> Hi, our logger was running.

Please do these simple tests:

- run "mlogger -v", it should report that it is writing slow/slow data into the history with rate 1 Hz (fetest 
should be running at this point, yes?)
- normally the history files are written into the experiment directory (where ODB is, etc) and have file names 
"*.hst". Observe that the files are growing. Use "ls -ltr". (mlogger and fetest should be running at this point, 
yes?)
- if all if this is happening, you can try to run "mhist" to see the history data

If all of the above works, but you still get nothing from the history plots in mhttpd, then we probably have a 
bug in midas and we would like very much to fix it. For this we will need some more information from you. I 
hope you have some time available to help us with this.

Hmm... the fetest history plots are not defined automatically, you have to create the history plot manually,
maybe this is where the problem happens. One thing to check here, the correct variable to plot
is "slow/slow", if I remember right.


K.O.


> I have tried restarting mlogger (even though we haven't
> changed variable names). We ran the following commands one after another and still no
> luck with history plot. Is there anything else that could be causing these problems?
> 
> Kind regards,
> Hassan 
> 
> 
================================================================================
==
> 
> [lm17773@it038146 ~]$ cd /opt/midas_software/midas/bin/
> [lm17773@it038146 bin]$ mhttpd
> [mhttpd,ERROR] [odb.cxx:1646:db_open_database,ERROR] Removed ODB client 'mhttpd',
> index 0 because process pid 20094 does not exists
> [mhttpd,ERROR] [odb.cxx:1646:db_open_database,ERROR] Removed ODB client 'Logger',
> index 1 because process pid 20214 does not exists
> [mhttpd,INFO] Removed open record flag from "/Experiment/Security/RPC hosts/Allowed hosts"
> [mhttpd,INFO] Removed exclusive access mode from "/Experiment/Security/RPC
> hosts/Allowed hosts"
> [mhttpd,INFO] Removed open record flag from "/Experiment/Security/mhttpd hosts/Allowed
> hosts"
> [mhttpd,INFO] Removed exclusive access mode from "/Experiment/Security/mhttpd
> hosts/Allowed hosts"
> [mhttpd,INFO] Removed open record flag from "/Logger/History"
> [mhttpd,INFO] Removed exclusive access mode from "/Logger/History"
> [mhttpd,INFO] Removed open record flag from "/Sequencer/State"
> [mhttpd,INFO] Removed exclusive access mode from "/Sequencer/State"
> [mhttpd,INFO] Removed open record flag from "/History/LoggerHistoryChannel"
> [mhttpd,INFO] Removed exclusive access mode from "/History/LoggerHistoryChannel"
> [mhttpd,INFO] Removed open record flag from "/Equipment/slow/Variables"
> [mhttpd,INFO] Removed exclusive access mode from "/Equipment/slow/Variables"
> [mhttpd,INFO] Removed open record flag from "/Equipment/Trigger/Statistics/Events per
> sec."
> [mhttpd,INFO] Removed exclusive access mode from "/Equipment/Trigger/Statistics/Events
> per sec."
> [mhttpd,INFO] Removed open record flag from "/Equipment/Trigger/Statistics/kBytes per
> sec."
> [mhttpd,INFO] Removed exclusive access mode from "/Equipment/Trigger/Statistics/kBytes
> per sec."
> [mhttpd,INFO] Removed open record flag from "/Equipment/Periodic/Variables"
> [mhttpd,INFO] Removed exclusive access mode from "/Equipment/Periodic/Variables"
> [mhttpd,INFO] Removed open record flag from "/Equipment/Scaler/Variables"
> [mhttpd,INFO] Removed exclusive access mode from "/Equipment/Scaler/Variables"
> [mhttpd,INFO] Corrected 10 ODB entries
> [mhttpd,INFO] Deleted entry '/System/Clients/20094' for client 'mhttpd' because it is
> not connected to ODB
> Mongoose web server will use SSL certificate file "/home/lm17773/online/ssl_cert.pem"
> Mongoose web server will use authentication realm "sampleexpt", password file
> "/home/lm17773/online/htpasswd.txt"
> mongoose web server is redirecting HTTP port 8080 to
> https://it038146.users.bris.ac.uk:8443
> mongoose web server is listening on the HTTP port 8080
> mongoose web server is listening on the HTTPS port 8443
> 
================================================================================
====
> 
> [lm17773@it038146 bin]$ mlogger
> [Logger,INFO] Deleted entry '/System/Clients/20214' for client 'Logger' because it is
> not connected to ODB
> Log     directory is /home/lm17773/online/
> Data    directory is same as Log unless specified in /Logger/channels/
> History directory is same as Log unless specified in /Logger/history/
> ELog    directory is same as Log
> SQL     database is localhost/sampleexpt/Runlog
> MIDAS logger started. Stop with "!"
> 
================================================================================
====
> [lm17773@it038146 bin]$ fetest
> Frontend name          :     fetest
> Event buffer size      :     10485760
> User max event size    :     4194304
> User max frag. size    :     4194304
> # of events per buffer :     2
> 
> Connect to experiment sampleexpt...
> OK
> Init hardware...frontend_init!
> Event size set to 10240 bytes
> Ring buffer wait sleep 1 ms
> OK
> time 1564131394, data 97.814758
> time 1564131395, data 96.592583
> time 1564131396, data 95.105652
> time 1564131397, data 93.358040
> time 1564131398, data 91.354546
> time 1564131399, data 89.100655
> time 1564131400, data 86.602539
> time 1564131401, data 83.867058
> time 1564131402, data 80.901703
> time 1564131403, data 77.714592
> Warning: bank RND4 has zero size
> time 1564131404, data 74.314484
> time 1564131405, data 70.710678
> time 1564131406, data 66.913063
> time 1564131407, data 62.932041
> 
================================================================================
====
> 
> 
> 
> 
> 
> 
> > > Hi,
> > > 
> > > We've been trying to run Fetest in the attempt of plotting the sine wave data on
> > > the history page on the web server. However each time we've tried running a new
> > > plot we have come across the error of 'no data' from the variables. In the
> > > status page we are clearly obtaining data from the frontend and it is updating
> > > the variable as expected in SLOW.
> > > 
> > > When setting up MIDAS we managed to produce a history plot from Fetest but are
> > > unable to do so any longer. We did have a go at modifying the Fetest code but
> > > created a backup before doing so and are now running the original backup.
> > > 
> > > What could be causing the Fetest data not to be showing in the history plot?
> > 
> > Is the logger running? (this application is handling the history data).
> > If yes: Did you change the variable names? If yes: restart the logger.

Currently one has to set the required flag in the ODB (e.g., /Programs/Logger/Required) to "y" for the program 
to appear on the "Programs page" and being able to start and stop the program easily.

However, if one wants to run with the "Prevent start on required progs" in /Experiment enabled, all the 
programs in the "Programs page" need to be running and one cannot have one of them stopped while still 
taking a run.

It would be nice to separate these two functionalities: Have a flag that makes the program appear on the 
"Programs page" and have a flag that controls the "Prevent start on required frogs" functionality.

> Currently one has to set the required flag in the ODB (e.g., /Programs/Logger/Required) to "y" for the program 
> to appear on the "Programs page" and being able to start and stop the program easily.
> 
> However, if one wants to run with the "Prevent start on required progs" in /Experiment enabled, all the 
> programs in the "Programs page" need to be running and one cannot have one of them stopped while still 
> taking a run.
> 
> It would be nice to separate these two functionalities: Have a flag that makes the program appear on the 
> "Programs page" and have a flag that controls the "Prevent start on required frogs" functionality.

I agree. All the programs should be always visible on the "programs" page, there should be /Programs/xxx/hidden to 
hide them, and /Programs/xxx/required should be used for "Prevent start on required progs".

K.O.

> > Currently one has to set the required flag in the ODB (e.g., /Programs/Logger/Required) to "y" for the program 
> > to appear on the "Programs page" and being able to start and stop the program easily.
> > 
> > However, if one wants to run with the "Prevent start on required progs" in /Experiment enabled, all the 
> > programs in the "Programs page" need to be running and one cannot have one of them stopped while still 
> > taking a run.
> > 
> > It would be nice to separate these two functionalities: Have a flag that makes the program appear on the 
> > "Programs page" and have a flag that controls the "Prevent start on required frogs" functionality.
> 
> I agree. All the programs should be always visible on the "programs" page, there should be /Programs/xxx/hidden to 
> hide them, and /Programs/xxx/required should be used for "Prevent start on required progs".

Konstantin, since you wrote the current "Programs" page, can you add that feature to the display (well, when you have time). I guess we 
event don't have to change the subdirectory structure (which might lead to incopatibilities), but just show a program if the "Start command" 
is non-null. If there is no start command, it does not make sense to start that program, so it can be hidden.

Stefan

I am working for the SuperCDMS collaboration on some DAQ issues for our upcoming
SNOLAB installation.  So far, the MIDAS sequencer seems to be a good paradigm
for us to do procedural tasks for our detectors and data running interspersed
with other protocols.  

In our testing we've found that the sequencer works very well for this kind of
activity, although it would be useful to have a kind of scripted "abort" for
when something goes wrong -- especially if the user selects to abort a run
sequence. 

Because the sequencer is setting various detector parameters to a certain value
before performing the tasks, the values will never be restored if the user
aborts the sequence.  Instead, perhaps there can be a portion of a MIDAS
sequence script which is instructed to happen on an abort.  Perhaps something
like all commands after a given tag like:

ON ABORT:

get run on a user-initiated abort?  

> it would be useful to have a kind of scripted "abort" for when something goes wrong ...

How about having the sequencer switching from the aborted sequence file to the special "abort" sequence file? That 
should be simple to implement if it is not already there.

K.O.

> > it would be useful to have a kind of scripted "abort" for when something goes wrong ...
> 
> How about having the sequencer switching from the aborted sequence file to the special "abort" sequence file? That 
> should be simple to implement if it is not already there.
> 
> K.O.

It's about the same effort if we jump to a specific label in a script or to a separate script. I just have to find some time to implement it.

Stefan

> It would be useful to have it be specified for each script.  Reason is that it's simpler, some scripts might only 
> change a few sensitive settings, then on abort it only has to set back to "normal" what it touched to begin with.  
> Also, the "normal" values are usually stored in local variables, so it's important to have those similarly accessible 
> to the "Abort" portion of the script.

Agree. So I will put a special optional label, which will be accessed upon abort.

Stefan

Is the midas CVS server set-up so that I can pull the newest 
version off the CVS server?

What would be my CVSROOT?
pserver:anoncvs@midas.psi.ch:/cvs/midas *this did not work* :)

Piotr

 

> Is the midas CVS server set-up so that I can pull the newest 
> version off the CVS server?
> 
> What would be my CVSROOT?
> pserver:anoncvs@midas.psi.ch:/cvs/midas *this did not work* :)
> 
> Piotr
> 
>  

In the Midas doc under "Quick Start"
http://midas.triumf.ca/doc/html/quickstart.html
you will find the proper cvs command for accessing the latest cvs Midas
version. The public pwd is cvs. You will only be able to checkout/update the
package.

> In the Midas doc under "Quick Start"
> http://midas.triumf.ca/doc/html/quickstart.html
> you will find the proper cvs command for accessing the latest cvs Midas
> version. The public pwd is cvs. You will only be able to checkout/update the
> package.

I cannot checkout module:
------------
01:52:16: pc2075.psi.ch: Operation timed out
01:52:16: cvs [checkout aborted]: end of file from server (consult above
messages if any)
------------

Could anybody add download tar package in the WWW interface of CVS repository.
I know the original CGI script has such a feature. Thanks.

> Is the midas CVS server set-up so that I can pull the newest 
> version off the CVS server?
> 
> What would be my CVSROOT?
> pserver:anoncvs@midas.psi.ch:/cvs/midas *this did not work* :)

I use:

setenv CVS_RSH ssh
cvs -d cvs@midas.psi.ch:/usr/local/cvsroot checkout midas

It works most of the time. Sometimes I get locking and "permission denied"
errors on some subdirectories, presumably when CVS is being reorganized or
when there are stale locks. Does not happen too often.

K.O.

As of svn rev 4807, src/system.c has an experimental implementation of POSIX shared memory. It is 
similar to the already existing implementation of MMAP shared memory, but uses POSIX shm_open() 
instead of directly mmapping the .xxx.SHM file.

There are several benefits to using POSIX shared memory:
1) on MacOS, the (unchangable?) maximum SYSV shared memory is about 2 Mbytes, too small for most 
MIDAS experiments. POSIX shared memory does not seem to have such a limit;
2) on Linux, when using SYSV shared memory, the .xxx.SHM files are tied to the shared memory keys 
using ftok(). If the .xxx.SHM files are located on an NFS-mounted filesystem, ftok() has been observed 
to malfunction and return the same key for different shared memory buffers, causing mighty confusing 
behaviour of MIDAS. (while "man ftok" discusses a theoretical possibility for such collisions, I have 
observed ftok() collisions first hand on a running experiment and it cost us several hours to understand 
why all the events go into the wrong event buffers). The present POSIX shared memory implementation 
does not have such a problem.

This implementation has received limited testing on Linux and MacOS, and it is now the default shared 
memory implementation on MacOS. Linux continues to use SYSV shared memory (ipcs & co). Windows 
uses it's own implementation of shared memory (same as mmap, the best I can tell).

svn 4807
K.O.

We had javascript ODBGet() and ODBSet() functions for some time now, permitting implementation of 
"page-reload-free" "self-updating" web pages. I finally got around to put all the javascript bits together 
to actually implement such a page. The main difference from a normal MIDAS "custom" page is the data 
update method - instead of fully reloading the page (via "<meta http-equiv="Refresh" content="60">" 
or javascript location.reload()) - I use ODBGet() to read new data from ODB and HTML DOM access to 
update it on the web page. Note that this is not quite AJAX because the load() function is synchronous 
and (i.e. on the MacOS 10.6 Safari web browser) completely freezes the web browser during data update 
(but no freeze on the Linux Firefox, go figure). An asynchronous ODBGet() should be easy to implement, 
but I can see how a fully asynchronous load() function would lose some of the simplicity of this 
example. (I hope elog does not mangle my example too much).
K.O.

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <title>PostAmp control</title>
  </head>

  <body>
    <h1>PostAmp control</h1>

    <script src='mhttpd.js'></script>
    <script type="text/javascript">

var numcrates = 2;
var numpachan;
var reloadTimerId = 0;

function load()
{
  document.getElementById('LastUpdated').innerHTML = "Reloading..." + new Date;

  var crates_table = document.getElementById('crates');
  var slots_table = document.getElementById('cards');

  var Csn = ODBGet('/Equipment/PostAmp/Settings/PACtrlSerialNo[*]');
  for (var i = 0; i < numcrates; i++)
    crates_table.rows[1+i].cells[1].innerHTML = Csn[i];

  var MaxTemp = ODBGet('/Equipment/PostAmp/Variables/MaxTemp[*]');
  for (var i = 0; i < numcrates; i++)
    crates_table.rows[1+i].cells[2].innerHTML = MaxTemp[i];

  var D_TP = ODBGet('/Equipment/PostAmp/Variables/D_TP[*]');
  var M_TP = ODBGet('/Equipment/PostAmp/Variables/M_TP[*]');

  for (var i = 0; i < numcrates; i++)
    crates_table.rows[1+i].cells[3].innerHTML = D_TP[i] + " / " + M_TP[i];

  var sn = ODBGet('/Equipment/PostAmp/Settings/PASerialNo[*]');
  for (var i = 0; i < numpachan; i++)
    slots_table.rows[1+i].cells[1].innerHTML = sn[i];

  var VoltageP  = ODBGet('/Equipment/PostAmp/Variables/VoltageP[*]');
  for (var i = 0; i < numpachan; i++)
    slots_table.rows[1+i].cells[2].innerHTML = VoltageP[i];

  var VoltageM  = ODBGet('/Equipment/PostAmp/Variables/VoltageM[*]');
  for (var i = 0; i < numpachan; i++)
    slots_table.rows[1+i].cells[3].innerHTML = VoltageM[i];

  var Temp      = ODBGet('/Equipment/PostAmp/Variables/Temp[*]');
  for (var i = 0; i < numpachan; i++)
    slots_table.rows[1+i].cells[4].innerHTML = Temp[i];

  var D_VTp     = ODBGet('/Equipment/PostAmp/Variables/D_VTp[*]');
  var M_VTp     = ODBGet('/Equipment/PostAmp/Variables/M_VTp[*]');

  for (var i = 0; i < numpachan; i++)
    slots_table.rows[1+i].cells[5].innerHTML = D_VTp[i] + " / " + M_VTp[i];

  var D_Thresh  = ODBGet('/Equipment/PostAmp/Variables/D_Thresh[*]');
  var M_ThreshA = ODBGet('/Equipment/PostAmp/Variables/M_ThreshA[*]');
  var M_ThreshB = ODBGet('/Equipment/PostAmp/Variables/M_ThreshB[*]');

  for (var i = 0; i < numpachan; i++)
    slots_table.rows[1+i].cells[6].innerHTML = D_Thresh[i] + " / " + M_ThreshA[i] + " / " + M_ThreshB[i];

  document.getElementById('LastUpdated').innerHTML = "Last updated: " + new Date;
}

function reload()
{
  clearTimeout(reloadTimerId);
  load();
  reloadTimerId = setTimeout('reload()', 10000);
}

function main()
{
  clearTimeout(reloadTimerId);

  document.writeln("<p id=LastUpdated>Last updated: </p>");

  document.writeln("<input type=button value='Reload' onClick='reload();'></input>");
  document.writeln("<input type=button value='TP enable' onClick='clearTimeout(reloadTimerId); 
ODBSet(\"/Equipment/PostAmp/Settings/Command\", \"gtp 1\"); reload();'></input>");
  document.writeln("<input type=button value='TP disable' onClick='clearTimeout(reloadTimerId); 
ODBSet(\"/Equipment/PostAmp/Settings/Command\", \"gtp 0\"); reload();'></input>");
  //document.writeln("<input type=button value='Thresh 100' onClick='clearTimeout(reloadTimerId); 
ODBSet(\"/Equipment/PostAmp/Settings/Command\", \"gvth 100\"); reload();'></input>");
  //document.writeln("<input type=button value='Vtest 200' onClick='clearTimeout(reloadTimerId); 
ODBSet(\"/Equipment/PostAmp/Settings/Command\", \"gvtest 200\"); reload();'></input>");

  document.writeln("Set VTp: ");
  document.writeln("<input type=input size=5 value='200' onKeyPress='if (event.keyCode==13) { 
clearTimeout(reloadTimerId); ODBSet(\"/Equipment/PostAmp/Settings/Command\", \"gvtest \" + 
this.value); reload(); }'></input>");

  document.writeln("Set Thresh: ");
  document.writeln("<input type=input size=5 value='100' onKeyPress='if (event.keyCode==13) { 
clearTimeout(reloadTimerId); ODBSet(\"/Equipment/PostAmp/Settings/Command\", \"gvth \" + 
this.value); reload(); }'></input>");

  document.write("<table id=crates border=1>");
  
  document.writeln("<tr align=center>");
  document.writeln("<th>Crate");
  document.writeln("<th>SerialNo");
  document.writeln("<th>MaxTemp");
  document.writeln("<th>D_TP / M_TP");
  document.writeln("</tr>");
  

  for (c = 0; c < numcrates; c++) {
    document.writeln("<tr align=center>");
    document.writeln("<td>" + c);
    document.writeln("<td>sn");
    document.writeln("<td>maxtemp");
    document.writeln("<td>d_tp/m_tp");
    document.writeln("</tr>");
  }
  document.writeln("</table>");
  
  document.write("<table id=cards border=1>");
  
  document.writeln("<tr align=center>");
  document.writeln("<th>Crate/Slot");
  document.writeln("<th>SerialNo");
  document.writeln("<th>V+5");
  document.writeln("<th>V-5");
  document.writeln("<th>Temp");
  document.writeln("<th>VTp");
  document.writeln("<th>Thresh");
  document.writeln("</tr>");
  
  for (c = 0; c < numcrates; c++) {
    for (s = 1; s <= 24; s++) {
      xchan = (c*24) + (s-1);
      document.writeln("<tr align=center>");
      document.writeln("<td>" + c + "/" + s + "/" + xchan);
      document.writeln("<td>sn");
      document.writeln("<td>vp");
      document.writeln("<td>vm");
      document.writeln("<td>temp");
      document.writeln("<td>d_vtpm/m_vtp");
      document.writeln("<td>d_thresh/m_thresha/m_threshb");
      document.writeln("</tr>");
    }
  }
  document.writeln("</table>");

  numpachan = xchan+1;
}

main();
reload();

//ODBSet('/Equipment/FgdWiener01/Settings/outputSwitch[8]', value);

    </script>

    <hr>
    <address><a href="xxx@xxx">Expt S1249</a></address>
<!-- Created: Tue Sep 21 15:44:39 PDT 2010 -->
<!-- hhmts start -->
Last modified: Wed Sep 22 08:30:31 PDT 2010
<!-- hhmts end -->
  </body>
</html>

> We had javascript ODBGet() and ODBSet() functions for some time now, permitting 
implementation of 
> "page-reload-free" "self-updating" web pages. I finally got around to put all 
the javascript bits together 
> to actually implement such a page.

Unfortunately the page has tons of JavaScript errors, probably happened during 
copy-and-paste to elog. Note that 
such files are better places as attachment. I attached a screen dump from the JS 
debugger inside Chrome which I 
use normally to debug JS.

> > We had javascript ODBGet() and ODBSet() functions for some time now, permitting 
> implementation of 
> > "page-reload-free" "self-updating" web pages. I finally got around to put all 
> the javascript bits together 
> > to actually implement such a page.
> 
> Unfortunately the page has tons of JavaScript errors, probably happened during 
> copy-and-paste to elog.

The attached errors all seem to be from cut-and-paste line breaks in the long "document.writeln()" statements. 
When the page runs, there are no errors from Firefox and Safari.

This example uses "document.writeln()" because the number of PostAmp devices displayed in the table is not 
known in advance and is potentially read from ODB at page load time.

K.O.

> The attached errors all seem to be from cut-and-paste line breaks in the long "document.writeln()" statements. 
> When the page runs, there are no errors from Firefox and Safari.

Then it would be good if you re-submit the file as an attachment so that other people can use it.

> This example uses "document.writeln()" because the number of PostAmp devices displayed in the table is not 
> known in advance and is potentially read from ODB at page load time.

This was not a criticism but just to show that there are different ways of constructing such a page, depending on the 
needs. So people have the choice. Anyhow I think it's very good to have some working examples for people to start 
with.

Dear MIDAS experts,

Greetings! 
I am currently utilizing MIDAS for our experiment and I have encountered an issue with our event builder, which was developed based on the example code 'eventbuilder/mevb.cxx'. I'm uncertain whether this is a genuine bug or an inherent feature of MIDAS.

The event builder fails to initiate the 10th run since its startup, requiring us to relaunch it. Upon investigating the code, I have identified that this issue stems from line 8404 of mfe.cxx (the version's hash is db94df6fa79772c49888da9374e143067a1fff3a). According to the code, the 10-run limit is imposed by the variable MAX_EVENT_REQUESTS in midas.h. While I can increase this value as the code suggests, it does not provide a complete solution, as the same problem will inevitably resurface. This complication unnecessarily hampers our data collection during long observation periods.

Despite the code indicating 'BM_NO_MEMORY: too many requests,' this explanation does not seem logical to me. In fact, other standard frontends do not encounter this problem and can start new runs as required without requiring a frontend relaunch.

I apologize for not yet fully grasping the intricate implementation of midas.cxx and mfe.cxx. However, I would greatly appreciate any suggestions or insights you can offer to help resolve this issue.

Thank you in advance for your kind assistance.