Execution time of the timed loop

Similar Questions

• Sequence structure flat inside the timed loop and execution order

  I have some problems trying to implement a flat sequence structure when you use a loop timed on a target of cRio VI

  I tried with or without the while loop around the structure of sequence flat, and I also tried to replace the 'Non-deterministic loop' with a timed loop

  The problem is that the program seems to run only once, then get stuck somewhere

  I am writing a program that performs the following operations as soon as possible:
  1. read the Pos_MC of entry on the FPGA
  2 send the value of Pos_MC to the VI target (on cRio CPU)
  3. calculate a value of output based on Pos_MC with a PID block ("exit PID')
  4. send 'PID output' to the FPGA
  5 write "PID output" analog output "MOOG".

  In addition, I want the program to return the measured value "Pos_MC" to a host VI for the recording of data

  So that the output of PID is calculated and sent to the FPGA as quickly as possible, I placed a flat sequence structure to ensure that it happens before you send the output to the nondeterministic loop for recording data

  Also, I want the digital input 'Stop' to be able to stop the loop deterministic (the timed loop)

  I read much more entries than that and the help of several PID and exit, but I rewrote the code for a single entry and exit to make it easier to illustrate

  Screenshot of the code is shown in 'target code.png' and 'fpga code.png.

  The VI themselves are attached in the next post (cannot attach files of more than 3)

  Question 1:
  Any advice on how to get this race? Thank you!

  Question 2:
  Is also my correct understanding in that, using this structure, each 0.9ms (fpga loop time) comes the following:
  1. the input ("Pos_MOOG") is read on the fpga
  2. the production of PID is calculated on the cRio with some delay to computation (for example 0.1ms)
  3. the output of PID is then written for analog output "MOOG" in all about 0, 1 - 0.2ms
  4. the FPGA program then waits until 0.9ms spent and repeat the process

  As opposed to the next pass whenever performing a loop is started on the FPGA:

  1. the FPGA reads the input and written on the output (the output of the execution of the previous loop PID)

  2. then the entry is sent the cRio, PID output is calculated and sent to the FPGA

  3. the new release of PID is maintained until the next time through the loop

  Thank you!

  PHG wrote:

  Thanks for the input guys, any advice as to how I could get the feature in scenario 1?

  I still say that the best route is just putting all the logic of the control in the FPGA.

  Other alternatives include 1) the use of DMA FIFO sedn data back or 2) use interruptions so that the FPGA code can not read the output level until the RT.

  DMA FIFOs are usually very limited, and I would not use them in this situation since I belive said it this code to do for the many outputs.

• How to create a control of time for the while loop?

  Hi all

  I want to control my time running of the loop. In other words, I want to stop everything in the execution of the loop after a time (in ms) that is defined by the user. For example user defines Control Panel for 5 seconds before a while loop runs and stops after 5 seconds.

  I don't know is it possible with the while loop. I managed with the timed loop, but this must be wrong with my application. Y at - it of the other loops for timed control if it is not possible with while loop? There is also a simple loop with .vi random number (0-1) as an attachment.

  Best regards

  Jick

  Hi again,

  I managed to solve my problem right after I posted my first message. I did it with the passage of time and the register shift (for the elapsed time of reset).

  Thanks for your replies anyway!

  Best R

  Jick

• How to shorten the execution time of the NXT (TETRIX & MATRIX toolkit) brick

  Hello

  How to shorten the execution time of the NXT brick?

  (TETRIX & MATRIX toolkit, running time)

  The software is 2012 LabVIEW for LEGO MINDSTORMS

  Thank you.

  

  

  Hi 40123157,

  You use the module in an appropriate manner, and there is no simple way to improve the time of loop iteration beyond what you've done. Here are my suggestions:

  (1) the i2c commands take a long time. In your application, it may speed up if you run only move the engine only when the engine speed has changed.

  (2) for this particular example, you do not use the release of the report engine. If this VI does not need to run it can be removed.

  (3) If you need to speed up execution other than that, as a user advanced LabVIEW, you can create a copy of the VI of engines to move and change it as you choose. All you have to to the "DC motors' entry is use cluster to array on the cluster, as shown below. I think you can speed it up by running all the settings before the loop (type sensor and fixed connection configuration), and removing the value of power if you send only the values between-100 and 100.

  (4) drawing on the screen can be slow you down here.

  

• Impossible to click on the buttons for the timed loop.

  Hello!

  I have a loop that is timed with a pace set by the user. And when the loop is running, I can't push any button of my GUI to stop it...

  I have to wait until a mistake or I stop the race.

  I can't put the diagram is too big and I think I don't have the right, but you have ideas?

  Ask me for more details.

  Thank you

  bejard wrote: timed loop is just in a structure of the event and I put 10 ms or 100ms.

  The program runs correctly (with this loop delay of 10ms/100 ms) like in the beginning, but I can't push any button or even change the tabs during the loop.

  You shouldn't have long extensions inside the event.  Which is supposed to stop your timed loop?

  I think that you have the option "Lock the front until the end of the occurrence" lit.  It will not press anything, until the end of everything for this case (including the timed loop).

  According to my experience, using a loop timed in a Windows system is a complete waste and often adds more overhead and questions.  Instead, I really think you need to use a State Machine.  When the button is pressed, you tell your state machine to move to the State the code inside your timed loop tracks.  You can use the State with the structure of the event to time your loop.  If you can go behind your state of event to your processing loop structure.  Just set the timeout on the structure of the event at any rate of loop you really want to.

• Execution time of the XML CVI functions increase when loop

  I wrote several functions with CVI who read XML files. I confirmed in the utility of monitoring resources I have cleaned all my lists, items, documents, etc. I found that when I loop one of the functions I created, the execution time increases. The increase is small, but it is sensitive and does not affect the performance of my.

  Are there other sources of memory I need to release? It seems that there is a leak memory somewhere, but I can't see where this increase.

  I am running LabWIndows/CVI 2009 on Windows 2008 Server. I closed my functions using TestStand 4.2.1. Any help would be appreciated!

  Thanks in advance,

  Kyle

  Hi Daniel,.

  After some playing around, it turns out that the source of my problem was due to running my program as a Debug version, rather than a Release. As soon as I build in a configuration of output, the function remains coherent and quick time loop.

  Thank you for the research on this problem for me.

  Kyle

• Should I wait until the end of the execution time of the query for the execution plan?

  Hello Experts,

  I want to see the execution plan of the query below. However, it takes more than 3 hours. Should I wait all the time to see the execution plan?

  Note: EXPLAIN PLAN for does not work. (I mean that I do not see the actual line number, etc. with EXPLAIN the PLAN of market)

  You can see the output of the execution plan when I canceled the execution after 1 minute.

  My first question is: what should I do to see the execution plan for queries running out of time time?

  2nd question: when I cancel the query during execution in order to see the execution plan, will I see the specific plan of execution or erroneous values? Because the first execution plan seems inaccurate, what do you think?

  question 3: why EXPLAIN the PLAN for the clause does not work? Also, should I use EXPLAIN the PLAN of the clause to this scenerio? Can I see the result of running for long time without her queries?

  Thnaks for your help.

  Oracle Database 11 g Enterprise Edition Release 11.2.0.2.0 - 64 bit Production

  PL/SQL Release 11.2.0.2.0 - Production

  CORE Production 11.2.0.2.0

  AMT for Linux: Version 11.2.0.2.0 - Production

  NLSRTL Version 11.2.0.2.0 - Production

  Select / * + GATHER_PLAN_STATISTICS NO_PARALLEL * / J.INVOICEACCOUNT, J.INVOICEID, J.INVOICEDATE, (T.LINEAMOUNT + T.LINEAMOUNTTAX) price

  of custinvoicejour j join custinvoicetrans t on

  substr (nls_lower (j.DataAreaId), 1, 7) = substr (nls_lower (t.dataareaid), 1, 7) and

  substr (nls_lower (J.INVOICEID), 1: 25) = substr (nls_lower (t.INVOICEID), 1: 25)

  where

  substr (nls_lower (T.DATAAREAID), 1, 7) = '201' and T.AVBROCHURELINENUM = 29457

  and substr (nls_lower (j.dataareaid), 1, 7) = '201' and

  J.INVOICEACCOUNT in

  (select IT. Drmpos.avtr_seg_cust_campend ACCOUNTNUM this where THIS. CAMPAIGN = '201406' and THIS. SEGMENT_LEVEL in (', 'E'))

  and J.AVAWARDSALES > 190

  and substr (nls_lower (J.AVBILLINGCAMPAIGN), 1, 13) = '201406'

  "and J.INVOICEDATE between ' 04.06.2014' and ' 13.06.2014 ';

  SQL_ID, dznya6x7st0t8, number of children 0

  -------------------------------------

  Select / * + GATHER_PLAN_STATISTICS NO_PARALLEL * / J.INVOICEACCOUNT,.

  J.INVOICEID, J.INVOICEDATE, (T.LINEAMOUNT + T.LINEAMOUNTTAX) price of

  CustInvoiceJour j join custinvoicetrans t on

  substr (nls_lower (j.DataAreaId), 1, 7) =

  substr (nls_lower (t.DataAreaId), 1, 7) and

  = substr (nls_lower (J.INVOICEID), 1: 25)

  substr (nls_lower (t.INVOICEID), 1: 25) where

  substr (nls_lower (T.DATAAREAID), 1, 7) = '201' and T.AVBROCHURELINENUM =

  29457 and substr (nls_lower, (j.dataareaid), 1, 7) = '201' and

  J.INVOICEACCOUNT in (select CE. ACCOUNTNUM of

  drmpos.avtr_seg_cust_campend this where THIS. CAMPAIGN = '201406' and

  IT. SEGMENT_LEVEL in (', 'E')) and J.AVAWARDSALES > 190 and

  substr (nls_lower (J.AVBILLINGCAMPAIGN), 1, 13) = '201406' and

  "J.INVOICEDATE between ' 04.06.2014' and ' 13.06.2014 '.

  Hash value of plan: 2002317666

  --------------------------------------------------------------------------------------------------------------------------------------------------------------

  | ID | Operation | Name                           | Begins | E - lines. A - lines.   A - time | Pads | Bed |  OMem |  1Mem | Used Mem.

  --------------------------------------------------------------------------------------------------------------------------------------------------------------

  |   0 | SELECT STATEMENT |                                |      1.        |      0 | 00:00:00.01 |       0 |      0 |       |       |          |

  |*  1 |  HASH JOIN |                                |      1.   3956.      0 | 00:00:00.01 |       0 |      0 |  2254K |  1061K | 2190K (0) |

  |*  2 |   HASH JOIN |                                |      1.     87.  16676. 00:00:01.64 |     227K |   3552.  3109K |  1106K | 4111K (0) |

  |*  3 |    TABLE ACCESS BY INDEX ROWID | CUSTINVOICEJOUR |      1.   1155 |  31889 | 00:00:01.16 |     223KO |     15.       |       |          |

  |*  4 |     INDEX RANGE SCAN | I_062INVOICEDATEORDERTYPEIDX |      1.   4943 |    134K | 00:00:00.83 |   45440 |      0 |       |       |          |

  |   5.    SIMPLE LIST OF PARTITION.                                |      1.  82360 |    173K | 00:00:00.08 |    3809 |   3537 |       |       |          |

  |*  6 |     TABLE ACCESS FULL | AVTR_SEG_CUST_CAMPEND |      1.  82360 |    173K | 00:00:00.06 |    3809 |   3537 |       |       |          |

  |   7.   TABLE ACCESS BY INDEX ROWID | CUSTINVOICETRANS |      1.   4560 |      0 | 00:00:00.01 |       0 |      0 |       |       |          |

  |*  8 |    INDEX RANGE SCAN | I_064INVLINENUMCAMPAIGNOFPRICE |      1.   4560 |      0 | 00:00:00.01 |       0 |      0 |       |       |          |

  --------------------------------------------------------------------------------------------------------------------------------------------------------------

  Information of predicates (identified by the operation identity card):

  ---------------------------------------------------

  1 - access("J".") "SYS_NC00299$"="T". "' SYS_NC00165$ ' AND SUBSTR (NLS_LOWER ('J'. "" "" REFFACTURE")(, 1, 25) = SUBSTR (NLS_LOWER ("T"." "" "REFFACTURE")(, 1, 25)).

  2 - access("J".") INVOICEACCOUNT '= SYS_OP_C2C ("EC". ". ACCOUNTNUM'))

  3 - filter("J".") AVAWARDSALES"> 190)

  4 - access("J".") SYS_NC00299$ "= U ' 201"AND "J". INVOICEDATE"> = TO_DATE(' 2014-06-04 00:00:00', 'syyyy-mm-dd hh24:mi:ss') AND

  "J"." SYS_NC00307$ "= U ' 201406"AND "J". INVOICEDATE"< = TO_DATE (' 2014-06-13 00:00:00 ',' syyyy-mm-dd hh24:mi:ss')))

  filter ((' J'. "INVOICEDATE' > = 'J' AND TO_DATE(' 2014-06-04 00:00:00', 'syyyy-mm-dd hh24:mi:ss') '." " SYS_NC00307$ "= U '201406' AND"

  "J"." INVOICEDATE"< = TO_DATE (' 2014-06-13 00:00:00 ',' syyyy-mm-dd hh24:mi:ss'))))

  6 filter (("CE". "SEGMENT_LEVEL" = A "OR"THIS"." SEGMENT_LEVEL "=" E"))

  8 - access("T".") SYS_NC00165$ "= U ' 201"AND "T". AVBROCHURELINENUM "= 29457)

  filter ("T". ("AVBROCHURELINENUM" = 29457)

  EXPLAIN PLAN FOR

  Select / * + GATHER_PLAN_STATISTICS NO_PARALLEL * / J.INVOICEACCOUNT, J.INVOICEID, J.INVOICEDATE, (T.LINEAMOUNT + T.LINEAMOUNTTAX) price

  of custinvoicejour j join custinvoicetrans t on

  substr (nls_lower (j.DataAreaId), 1, 7) = substr (nls_lower (t.dataareaid), 1, 7) and

  substr (nls_lower (J.INVOICEID), 1: 25) = substr (nls_lower (t.INVOICEID), 1: 25)

  where

  substr (nls_lower (T.DATAAREAID), 1, 7) = '201' and T.AVBROCHURELINENUM = 29457

  and substr (nls_lower (j.dataareaid), 1, 7) = '201' and

  J.INVOICEACCOUNT in

  (select IT. Drmpos.avtr_seg_cust_campend ACCOUNTNUM this where THIS. CAMPAIGN = '201406' and THIS. SEGMENT_LEVEL in (', 'E'))

  and J.AVAWARDSALES > 190

  and substr (nls_lower (J.AVBILLINGCAMPAIGN), 1, 13) = '201406'

  "and J.INVOICEDATE between ' 04.06.2014' and ' 13.06.2014 ';

  SELECT * FROM table (DBMS_XPLAN. DISPLAY_CURSOR);

  SELECT * FROM table (DBMS_XPLAN. DISPLAY_CURSOR ('7h1nbzqjgwsp7', 2));

  SQL_ID, 7h1nbzqjgwsp7, number of children 2

  EXPLAIN PLAN for select / * + GATHER_PLAN_STATISTICS NO_PARALLEL * /.

  J.INVOICEACCOUNT, J.INVOICEID, J.INVOICEDATE,

  (T.LINEAMOUNT + T.LINEAMOUNTTAX) join price j custinvoicejour

  CustInvoiceTrans t on substr (nls_lower (j.dataareaid), 1, 7) =

  substr (nls_lower (t.DataAreaId), 1, 7) and

  = substr (nls_lower (J.INVOICEID), 1: 25)

  substr (nls_lower (t.INVOICEID), 1: 25) where

  substr (nls_lower (T.DATAAREAID), 1, 7) = '201' and T.AVBROCHURELINENUM =

  29457 and substr (nls_lower, (j.dataareaid), 1, 7) = '201' and

  J.INVOICEACCOUNT in (select CE. ACCOUNTNUM of

  drmpos.avtr_seg_cust_campend this where THIS. CAMPAIGN = '201406' and

  IT. SEGMENT_LEVEL in (', 'E')) and J.AVAWARDSALES > 190 and

  substr (nls_lower (J.AVBILLINGCAMPAIGN), 1, 13) = '201406' and

  "J.INVOICEDATE between ' 04.06.2014' and ' 13.06.2014 '.

  NOTE: cannot fetch SQL_ID plan: 7h1nbzqjgwsp7, CHILD_NUMBER: 2

  Check the value of SQL_ID and CHILD_NUMBER;

  It could also be that the plan is no longer in the cursor cache (check v$ sql_plan)

  NightWing wrote:

  Randolf,

  I don't understand. What you hear from the above statement that you mean A-lines and E will be incorrect, but the ratio between them remain the same. Therefore, you can deduct the bad things by comparing the differences.

  Thus, A-lines always give a wrong result for cancellation of queries, isn't it?

  Charlie,

  I think that Martin gave a good explanation. Here's another example that hopefully makes more obvious things:

  17:56:55 SQL >-things go very wrong here with a small buffer cache

  17:56:55 SQL >-T2 lines are badly scattered when you access through T1. FK

  17:56:55 SQL >--

  17:56:55 SQL >-"Small job" approach would have been a good idea

  17:56:55 SQL >-if the estimate of 100 iterations of the loop was correct!

  17:56:55 SQL > select

  17:56:55 (t2.attr2) count 2

  17:56:55 3 of

  17:56:55 4 t1

  17:56:55 5, t2

  17:56:55 6 where

  17:56:55   7  /*------------------*/

  17:56:55 8 trunc (t1.attr1) = 1

  17:56:55 9 and trunc (t1.attr2) = 1

  17:56:55 10 / *-* /.

  17:56:55 11 and t1.fk = t2.id

  17:56:55 12.

  T1

  *

  ERROR on line 4:

  ORA-01013: user has requested the cancellation of the current operation

  Elapsed time: 00:04:58.30

  18:01:53 SQL >

  18:01:53 SQL > @xplan_extended_display_cursor ' ' ' ' 'ALLSTATS LAST + COST.

  18:01:53 SQL > set echo off verify off termout off

  SQL_ID, 353msax56jvvp, number of children 0

  -------------------------------------

  SELECT count (t2.attr2) from t1, t2 where

  / / *-* trunc (t1.attr1) = 1 and

  trunc (T1.attr2) = 1 / *-* / and t1.fk = t2.id

  Hash value of plan: 2900488714

  ------------------------------------------------------------------------------------------------------------------------------------

  | ID | The NEST | DSB | Operation | Name | Begins | E - lines. Cost (% CPU). A - lines.   A - time | Pads | Bed |

  ------------------------------------------------------------------------------------------------------------------------------------

  |   0 |     |   7. SELECT STATEMENT |        |      1.        |  4999 (100) |      0 | 00:00:00.01 |       0 |      0 |

  |   1.   0 |   8 2 GLOBAL TRI |        |      1.      1.            |      0 | 00:00:00.01 |       0 |      0 |

  |   2.   1.   5.   NESTED LOOPS |        |      1.        |            |  57516 | 00:04:58.26 |     173K |  30770 |

  |   3.   2.   3.    NESTED LOOPS |        |      1.    100.  4999 (1) |  57516 | 00:00:21.06 |     116K |   3632.

  |*  4 |   3.   1.     TABLE ACCESS FULL | T1 |      1.    100.  4799 (1) |  57516 | 00:00:00.19 |    1008 |   1087 |

  |*  5 |   3.   2.     INDEX UNIQUE SCAN | T2_IDX |  57516 |      1.     1 (0) |  57516 | 00:00:20.82 |     115K |   2545 |

  |   8 2 2 |   4.    TABLE ACCESS BY INDEX ROWID | T2 |  57516 |      1.     2 (0) |  57516 | 00:04:37.14 |   57516 |  27138 |

  ------------------------------------------------------------------------------------------------------------------------------------

  Information of predicates (identified by the operation identity card):

  ---------------------------------------------------

  4 filter ((TRUNC ('T1'. "ATTR1") = 1 AND TRUNC ('T1'. " ATTR2') = 1))

  5 - access("T1".") FK '= 'T2'.' (ID')

  You say here that I canceled a query after about 5 minutes, and looking at the statistics of content (RowSource) I can already say the following:

  1. the estimation of cardinality of T1 is far - the optimizer estimated 100 lines, but it actually generated more than 57000 lines when the query was cancelled. If this definitely seems like a candidate at the origin of the problems

  2. the query has spent most of the time in search of random table T2

  So while it is true that I don't know final A-lines of this cancelled query information, I can still say a lot of this and begin to deal with the problems identified so far.

  Randolf

• execution time of the procedure

  Hello
  
  I'm working on the Conversion project, there are 7 different procedures that execute one after the other. It takes nearly 17 hours to complete one conversion.
  My question is how can I find out what procedure and/or SQL takes maximum time so that I can fix it. We used dynmaic sql strongly to INSERT/CHANGE/REMOVE.
  We use Oracle 9i.
  
  I tried to use v$ session_longops but there are so many tiny Jules Destrooper in the procedure, which lasts less than 6 seconds to run, v$ session_longops does not display any result.
  

  DBMS_APPLICATION_INFO.SET_MODULE(  module_name => 'Proc1', action_name => 'Start'); 
  DBMS_APPLICATION_INFO.set_action(action_name => 'Just Started');

  Thank you
  Sandy
  
  Published by: Sandy310 on July 27, 2011 14:42

  You can try to create a table to record the execution time of each procedure...
  For example:

  -table of log´s
  create table executation_log (obj_name varchar2 (120),)
  VARCHAR2 (120) of the event.
  time_execute timestamp);

  -log´s procedure
  create or replace procedure prc_log (p_obj_name in varchar2,
  p_event in varchar2)
  is

  pragma autonomous_transaction;

  Start

  insert into executation_log (obj_name, event, time_execute)
  values(p_obj_name,p_event,SYSTIMESTAMP);

  end prc_log

  declare

  Start

  -call the log´s procedure
  prc_log (p_obj_name-online 'frist_object',
  p_event-online 'start');

  -call your drifter
  frist_object;

  -After the procedure of log´s you call compare the process start and end
  prc_log (p_obj_name-online 'frist_object',
  p_event-online "finish");

  -new
  prc_log (p_obj_name-online 'second_object',
  p_event-online 'start');

  second_object;

  -call once again, once again, once again
  prc_log (p_obj_name-online 'second_object',
  p_event-online "finish");

  end;

  -Drifter, then select table log´s
  Select *.
  of e executation_log
  order of e.time_execute

  Thank you...

• Execution time of the steps

  Hello

  I want to use the stopwatch or a timer noted the moment to take the step bit (say some time by three steps in a sequence.)

  How can I do that I have not found a ts timerin.

  Hello

  You can add a step of instruction before your efforts, with the expression: Locals.intialTime = (seconds).

  After your steps, is the expression of the runtime: Locals.executionTime = Seconds() - Locals.initialTime.

  The result is in seconds.

  Bruno

• Why the execution time increases with a while loop, but not with "run continuously?

  Hi all

  I have a problem of severe weather that I don't know how to fix it because I don't know exactly where it comes from.

  I order two RF switches via a data acquisition card (NI USB-6008). One job at the same time can be selected on each switch. Basically, the VI created for this feature (by a colleague) resets all the outputs of acquisition data and active then those desired. It has three entrances, two chain simp0le controls and a cluster table, that contains the list of all the outputs and some practical information to know what is connected (specific to my application).

  I use this VI in a complex application, and I have some problems with the execution time, which increased whenever I said the VI, so I did a test VI (TimeTesting.vi) to determine where the problem came. In this special VI I record the execution time in a csv file to analyze then with excel.

  After several tries, I found that if I run this criterion VI with the while loop, execution on every cycle time increases, but if I remove the while loop and use the funtionnality "Continuous run", the execution time remains the same. In my high level application, I have while loops and events, and so the runtime increases too.

  I someone could explain to me why execution time increases and how can we avoid this? I have attached my VI test and the necessary subVIs, as well as an image of a graph that shows the execution time with a while loop and «run permanently»

  Thanks a lot for your help!

  Your SetReset_DO VI creates a channel whenever it is called.  And that you never delete a task.

  When running continuously, that it's as if it only runs once and LabVIEW has internal mechanisms to close references that will not be used again.  When a VI is used as a Subvi, LV does not know if she will be called again, and lacks these things until the first level VI stops. You have a memory leak.

  Just as you open and close your file outside the loop for, create your channel out of the loop.

  Lynn

• sampling time changed the buckle timed

  Hello world

  I use the timed loop to control the DC motor with the vi of PID. in the loop and the sampling time are defined as 0.01 s. However, after I added a few other screws in the loop, for example, writing of measure file.vi, to collect the errors between the angle and the practical perspective of the engine for the time histroty the movement of the motor, we find that the sampling time changed, not always 0.01 s before the vi has been added, but 0.01 or 0.02 s. the entire program desinged to be fininshed with 7 s, now's done it at 9.4 s, that is, execution of the loop time is extended.

  Another thing is, if the sampling time is defined as s 0.05, the sampling time is always 0.05 s and the execution time of the loop is always 7 s as predined, regardless of writing custom file.vi is added in the loop or not.

  As a result, I think that if the complexity of the loop is incresead and time of sampling sets is small, then the actual sampling time will be modified due to the design of things load in the timed loop. What is the reason? If so, are there methods to solve?

  It is important: the collection of the angular error of the engine in the time histrory is very important, which will be used to show the correctness of the settings KP, KI and KD.

  A friend suggested using the queue vi, but I don't really know how to use them. Can someone give some instructions?

  Thanks a lot!

  See you soon

  Cram features in a timed loop is like stuffing 5 books you know that in a book bag 3. The timed loop is only really practical on a rt system, but even in this case, if the code inside requires more time than the period of the loop, there is no magic that the loop can do to increase the execution time. Just point out you that the loop is late. The solution is to remove features from the inside of the loop. Writing to a file of measure is one of the worst if you write to a text file. Look at the producer/consumer model of design that you have examples of. There, you will have a normal loop that you will write to a queue, and a second loop will process data in the queue. Use file > open...

• passing the value and to timed loop

  Hello everyone,

  I'm working on a VI that consists of a timed loop which takes values in a file every 6 ms and writes it to an output file. Inside this timed loop, there is also a MATLAB block that calculates a parameter based on the value. based on this parameter, that a marker is set to 0 or 1 (planned) to operate as a Boolean marker.

  The problem arises when the marker is set to 1. I need an additional structure any that waits five seconds (without stopping the timed loop iterations) and a 'stop' button is not pressed an additional string is placed in the output file. I wish for the marker to get back to 0 if you press the 'stop' button and not string to put in the file.

  The main problem seems to be the use of a structure outside the timed loop. I can't have a while loop or any structure that waits 5 seconds inside the timed loop. And if I let him out he does not have the value of the marker second structure during execution of the timed loop.

  + Any ideas on what the structure to be used during the 5 seconds Timeout? (I tried a while loop)
  + Use a local or global variable for the marker? (I tried briefly, but as a local variable, I couldn't choose a variable defined in the MATLAB block, and I don't understand global variables in LabVIEW)

  I enclose a simplified version of the VI as well as a sample input file in case it can help visualize.

  Thank you
  DAVA

  So far, there are a few problems with your solution, but first of all, I will try to help answer your original question.

  You are right that you can't have a structure inside the timed loop which waits five seconds without blocking execution of the timed for the same period. You are also right that you cannot simply communicate through cables to an external structure. If you exit a loop of wire in the other, which creates a dependency of data flow, which means that the data loop cannot run at all until another loop ends its execution entirely and send data.

  You have two options:

  • Don't actually use a wait function to determine if the 5 seconds elapsed. Use the Express VI of time elapsed (search the palette). He just guard track of how much time has passed since the last reset. It does not wait. If you are safe to use inside your loop timed in a case that is triggered when the marker value becomes 1. Also check the Boolean command in this case Structure to decide if you should output the data in the file.
  • Use an outer loop as in the example you posted, but use screws of the range of synchronization to send data between the parallel loop. Consider a queue.

  But overall, I don't think there is much chance of this work very well. No way, the Matlab Script node running fast enough to run at a time of 6ms. Also no way it works in a deterministic way at all. He needs to communicate with an external program, so its execution time is really unlimited.

• How to measure the execution time of a specific to a VI process?

  Hello! My VI has two processes: compression and edge detection image and I'm trying to measure the execution time for the process of detection of edge of my VI, but I don't know how to do. Please give me some ideas on how to do it. Thank you!

  There are several ways that you can do.

  -L' one is using the number of cycles before and after your vi to get time like here: http://digital.ni.com/public.nsf/allkb/6F6B9F4E149C80578625652800784764

  - or use the profiling: https://zone.ni.com/reference/en-XX/help/371361H-01/lvhowto/profiling_vis/

  Edit: If you're open to suggestions:

  -You have not to load the image inside the loop instead, make him outside of the loop.

  - And I see of many IMAQ buffers are not removed properly. You can have everything at once by Images (No) by logging in to Boolean TRUE: http://zone.ni.com/reference/en-XX/help/370281P-01/imaqvision/imaq_dispose/

• Leak memory in real time caused by VISA Read and timed loop of data nodes? Is not supposed.

  In collaboration with LV 8.2.1 in real time to develop applications that monitor or emulate computers on bus RS-422.   The following screenshots have been taken an application that monitors a transmission of 200 Hz.  After a few hours, the PXI station would break a range impressive messages angry... most involving something about memory loss.  After much hair pulling and passing money, my partner has discovered while looking at the available memory on the controller of loss of memory occurred at each loop containing a VISA read and propagation of error using the data nodes (see Leak.jpg of memory).  He concluded that if he went to the propagation of the error to the regular old shift registers, then the available memory was rock-solid.  (has the Leak.jpg of No memory)

  Any ideas of what could be the cause?  Do you see not any problem with the way that we code these kinds of loops?  We always strive to optimize the way in which we use the memory on our urgent requests and VISA readings and DAQmx bed give us the heartache more than ever, we are able to allocate memory for these screws some tips?

  Dan Marlow

  GDLS

  Hi thisisnotadream,

  This problem has been reported, and you seem to be exactly reproduce the conditions required to see this problem. This was reported to R & D (# 134314) for further investigations. There are several possible solutions, of which one is the one you have already found the wiring error directly in the loop. Other situations which give rise to no memory leak are:

  1 if the bytes of the property node port is not there and has read lies in each iteration and time-outs resulting are ignored.

  2. If the structure of the deal is gone and just blindly check the bytes to the port and read each iteration.

  3. If the timed loop is transformed into a while loop.

  Thanks for the comments!

  Kind regards

  Stephen S.

• Rate the triggered loop of the timed iterations of TTL

  Hi all

  I have a camera control VI that awaits the shutter of the camera TTL information and use it as a source of synchronization for a timed loop. In this timed loop, the camera is read and analyzed. Program should respond as soon as possible a new image and that's why I put the timed loop to "Throw missing items" so that it does not seek to catch up (events im trying to detect is quite rare and last several frames).

  The problem is this: when I put the camera for a certain numebr of frameworks (e.g. 10,000) sometimes due to discarded frames ever loop iteration number the last number of frame expected and do not remove (it remains to 9.998 for example). I noticed I can stop it by deselecting "maintain phase." However, it is clear to me what happens exactly with these settings in a situation of TTL triggered.

  It is true that the loop passes the new data directly but starts the next loop the correct number of iteration (+ 1)? Or something else happening?

  IM grateful for any help!

  Dear j.win,

  If you deselect the option 'Maintain the Original Phase', in fact you never will reject any iteration, whatever the value "Discard missed items." On the contrary, the loop will try to catch up the iterations of the end.

  Use of a source of external synchronization (for example your TTL) instead of a source of internal synchronization does not change. You can use the 'period' entrance (dt) of the loop timed to specify when the loop is supposed to go (the unit is the "ticks" in the case of an external synchronization source). A value of '1' means that test loop to iterate over all the graduations of external synchronization source. If for any reason any iteration lasts longer than that, you'll have an iteration "end". Also with a value of '1', it is not possible to change the "phase", then the parameter "Initial Phase to maintain" will be defined only weather or not ignore you the iteration. If 'Maintain initial Phase' is set to false, the loop will run immediately after an end iteration to run always, but a little of the latter. If the 'Maintain initial Phase' is true, the loop will run immediately after an iteraion end if the option 'remove point missed' is false otherwise the loop will jump the iteration.

  It's more clear now?

  Kind regards