I have a two broken VIs with front panels that open fine, but I can't edit or run them, or open theis block diagrams.
One of these was made as a replacement for the first when it started to have this problem. I need to at least find out how to avoid this problem in future, so I don't lose work on bigger VIs.
I'm not sure if it makes any difference, but I very recently upgraded to LabVIEW 2013.
Thank you in advance.
This is the error I get when I try to run them:
"
VI has a bad connection to or cannot find a subVI or external routine.
This VI has a bad connection to or cannot find a subVI or external routine but
it has no block diagram to show or fix the error. You must find or correct the
subVI or external routine. Check for more information in the Explain dialog box
in Get Info.
"
Before reverting to a previous version (using dropbox) I got a different error with one of them:
"
LabVIEW: Generic error.
An error occurred loading VI 'sweep harmonics first test.vi', LabVIEW load
error code 6: Could not load the block diagram.
"
One situation how this happened.
Sometime LabVIEW crashes, and it restart. After restart, LabVIEW will ask you to recover the autosaved code.
I personally always discard those autosaved code. If you do choose to recover autosaved code, there is a chance the recovered code is corrupted. Once you save corrupted code to disk, you are probably going to lose the ability to open/save the block diagram ever again.
Having a version control system is usually a way to avoid minimize the damage when LabVIEW crashes. At worst, you loose maybe an hour worth of work.
If you can't open Block Diagram of your VI, first check the suggestion by #Rodrigo - it is most likely just a "compiled" VI, which has Block Diagram removed.
If you think there is Block Diagram inside and it is just corruped - you may contact NI support. And if you want to look deeper by yourself, extract the VI to XML using pyLabview, and look into the XML - there you can modify every single part of the VI. For example, you may start removing parts until it starts working.
I wouldn't go into manual VI editing unless you have at least a dozen of affected files though. For a single file, it will be faster to re-create it in LabVIEW instead of trying to understand the internals. If many files are affected - may be worth finding the issue in one, as other files probably have the same glitch, so you can make a script which extracts, modifies and re-creates VIs automatically.
From the sound of it, I believe what happens is that you are trying to run the VI's created as "DATA" for an executable, instead of the actual source VI's.
When you build an executable LabVIEW creates a copy of all the Top Level VI's dependencies into the support (DATA) folder which should be in the same directory as your executable.
Try opening the VI's that are marked as not having a block diagram and navigate to File>>VI Properties to check the path from which the VI is being loaded. If it's not the original VI, you can just replace it.
Related
When I save a method and get back to it later, all of my variable names become temp and all of my parameters becomes arg and the code indentation get changed.
Any thoughts on how I can fix this?
The behaviour that you are experiencing is not code formatting at all. You immage is experiencing an issue where it can't access original source code. Thus it uses a backup solution and decomples method bytecode. During the compilation process the variable names are erased, so they can't be re-created during the decompilation, and generic substitudes are used instead.
Now, why you are missing sources is another question. First of all it's important to check if you get some exceptions. Often these happen when you open or save your image, but also thaty may occur when you save methods.
Depending on the Pharo version you may be missing .changes or .sources files. This often happens when you more an image without moving other supporting files.
My Labview Program works like a charm, until I look at the Block Diagram. No changes are made. I do not Save. Just Ctrl+E and then Ctrl+R.
Now it does not work properly. Only a Restart of Labview fixes the problem.
My Program controls two Scanner arrays for Laser Cutting simultaneously. To force parallel working, I use the Error handler and loops that wait for a signal from the Scanner. But suddenly some loops run more often than they should.
What does majorly happen in Labview when I open the Block diagram that messes with my code?
Edit:
Its hard to tell what is happening without violating my non-disclosure agreement.
I'm controlling two independent mirror-Arrays for Laser Cutting. While one is running one Cutting-Job, the other is supposed to run the other Jobs. Just very fast. When the first is finished they meet at the same position and run the same geometry at the same slow speed. The jobs are provided as *.XML and stored as .net Objects. The device only runs the most recent job and overwrites it when getting a new one.
I can check if a job is still running. While this is true I run a while loop for the other jobs. Now this loop runs a few times too often and even ignores WAIT-blocks to a degree. Also it skips the part where it reads the XML job file, changes the speed part back to fast again and saves it. It only runs one time fast.
#Joe: No it does not. It only runs once well. afterwards it does not.
Youtube links
The way it is supposed to move
The wrong way
There is exactly one thing I can think of that changes solely by opening the block diagram.
When the block diagram opens, any commented-out or unreachable-code-compiler-eliminated sections of code will load their subVIs. If one of those commented out sections of code were somehow interfere with your running code, you might have an issue.
There are only two ways I know of for that to interfere... both of them are fairly improbable.
a) You have some sort of "check for all VIs in memory" or "check for all types in memory" that you're using as a plug-in system. When the commented-out sections load, that would change the VIs in memory. Such systems are not uncommon when parsing XML, so maybe.
b) You are using Run VI method for some dynamically invoked VI to execute as a top-level VI, but by loading the diagram, it discovers that it is a subVI of your current program. A VI cannot simultaneously be top-level and a subVI, so the call to Run VI returns an error.
That's it. I can't think of anything else. Both ideas seem unlikely, but given your claim and a lack of a block diagram, I figured I'd post it as a hypothesis.
In the improbable case someone has a similar problem. The problem was a xml file that was read during run time. Sometimes multiple instances tried to access it and this produced the error.
Quick point to check: are Debug and "retain data in wires" disabled? While it may not change the computations, but it may certainly change the timing of very tight loops, and that was one of the unexpected program behaviors, OP was referring to.
My firm's Access database has been having some serious problems recently. The errors we're getting seem like they indicate corruption -- here are the most common:
Error accessing file. Network connection may have been lost.
There was an error compiling this function.
No error, Access just crashes completely.
I've noticed that these errors only happen with a compiled database. If I decompile it, it works fine. If I take an uncompiled database and compile it, it works fine -- until the next time I try to open it. It appears that compiling the database into a .ACCDE file solves the problem, which is what I've been doing, but one person has reported that the issue returned for her, which has me very nervous.
I've tried exporting all of the objects in the database to text, starting with a brand new database, and importing them all again, but that doesn't solve the problem. Once I import all of the objects into the clean database, the problem comes back.
One last point that seems be related, but I don't understand how. The problem started right around the time that I added some class modules to the database. These class modules use the VBA Implements keyword, in an effort to clean up my code by introducing some polymorphism. I don't know why this would cause the problem, but the timing seems to indicate a relationship.
I've been searching for an explanation, but haven't found one yet. Does anyone have any suggestions?
EDIT: The database includes a few references in addition to the standard ones:
Microsoft ActiveX Data Objects 2.8
Microsoft Office 12.0
Microsoft Scripting Runtime
Microsoft VBScript Regular Expressions 5.5
Some of the things I do and use when debugging Access:
Test my app in a number of VM. You can use HyperV on Win8, VMWare or VirtualBox to set up various controlled test environments, like testing on WinXP, Win7, Win8, 32bit or 64 bits, just anything that matches the range of OS and bitness of your users.
I use vbWatchDog, a clever utility that only adds a few classes to your application (no external dependency) and allows you to trap errors at high level, and show you exactly where they happen. This is invaluable to catch and record strange errors, especially in the field.
If the issue appears isolated to one or a few users only, I would try to find out what is special about their config. If nothing seems out of place, I would completely unsintall all Office component and re-install it after scrubbing the registry for dangling keys and removing all traces of folders from the old install.
If your users do not need a complete version of Access, just use the free Access Runtime on their machine.
Make sure that you are using consistent versions of Access throughout: if you are using Access 2007, make sure your dev machine is also using that version and that all other users are also only using that version and that no components from Access 2010/2013 are present.
Try to ascertain if the crash is always happening around the same user-actions. I use a simple log file that I write to when a debugging flag is set. The log file is a simple text file that I open/write to/close everytime I log something (I don't keep it open to make sure the data is flushed to the file, otherwise when Access crashes, you may only have old data in the log file as the new one may still be in the buffer). Things I log are, for instance, sensitive function entry/exit, SQL queries that I execute from code, form open/close, etc.
As a generality, make sure your app compiles without issue (I mean when doing Debug > Compile from the IDE). Any issue at this stage must be solved.
Make absolutely sure you close all open recordsets, preferrably followed by setting their variables to Nothing. VBA is not as sensitive as it used to be about dangling references, but I found it good practice, especially when you cannot be absolutely sure that these references will be freed (especially when doing stuff at Module-level or Class-level for instance, where the scope may be longer-lived than expected).
Similarly, make sure you properly destroy any COM object you create in your classes (and subs/functions. The Class_Terminate destructor must explicitly clean up all. This is also valid when closing forms if you created COM objects (you mentioned using ADOX, scripting objects and regex). In general keeping track of created objects is paramount: make sure you explicitly free all your objects by resetting them (for instance using RemoveAll on a dictionary, then assigning their reference to Nothing.
Do not over-use On Error Resume or On Error Goto. I almost never use these except when absolutely necessary to recover from otherwise undetectable errors. Using these error trapping constructs can hide a lot of errors that would otherwise show you that something is wrong with your code. I prefer to program defensively than having to handle exceptions.
For testing, disable your error trapping to see if it isn't hiding the cause of your crashes.
Make sure that the front-end is local to the user machine, You mention they get their individual front-end from the network but I'm not sure if they run it from there or if it it copied on their local machine. At any rate, it should be local not on a remote folder.
You mention using SQL Server as a backend. Try to trace all the queries being executed. It's possible that the issue comes from communication with SQL Server, a corrupt driver, a security issue that prevents some queries from being run, a query returning unexpected data, etc. Watch the log files and event log on the server closely for strange errors, especially if they involve security.
Speaking of event log, look for the trace of the crash in the event log of your users. There may be information there, however cryptic.
If you use custom ribbon actions, make sure thy are not causing issues. I had strange problems over time with the ribbon. Log all all function calls made by the ribbon.
Good news, my c64 ist still running after lots of years spending time on my attic..
But what I always wanted to know is:
How can I automatically load & run a program from a floppy disk that is already inserted
when I switch on the c64?
Some auto-running command like load "*",8,1 would be adequate...
Regards
MoC
You write that a command that you type in, like LOAD"*",8,1 would be adequate. Can I assume, then, that the only problem with that particular command is that it only loads, but doesn't automatically run, the program? If so, you have a number of solutions:
If it's a machine language program, then you should type LOAD"<FILENAME>",8,1: and then (without pressing <RETURN>) press <SHIFT>+<RUN/STOP>.
If it's a BASIC program, type LOAD"<FILENAME>",8: and then (without pressing <RETURN>) press <SHIFT>+<RUN/STOP>.
It is possible to write a BASIC program such that it automatically runs when you load it with LOAD"<FILENAME>",8,1. To do so, first add the following line to the beginning of your program:
0 POKE770,131:POKE771,164
Then issue the following commands to save the program:
PRINT"{CLR}":POKE770,113:POKE771,168:POKE43,0;POKE44,3:POKE157,0:SAVE"<FILENAME>",8
This is not possible without some custom cartridge.
One way to fix this would be getting the Retro Replay cartridge and hacking your own code for it.
I doubt there is a way to do it; you would need a cartridge which handles this case and I don't think one like that exists.
A better and more suitable solution is EasyFlash actually. Retro Replay is commonly used with its own ROM. Since it is a very useful cartridge by default ROM, I would never flash another ROM to it. Also it is more expensive than EasyFlash if you don't have any of those cartridges.
At the moment, I have Prince Of Persia (!) ROM written to my EasyFlash and when I open my c64, it autoruns just like you asked for.
Not 100% relevant, but C128 can autoboot disks in C128 mode. For example Ultima V (which has musics on C128 but not on C64 or C128 in C64 mode) autoboots.
As for cartridges, I'd recommend 1541 Ultimate 2. It can also run games from module rom images (although Prince of Persia doesn't work for me for some reason, perhaps software issue?), but you also get rather good floppy emulator (which also makes it easier to transfer stuff to real disks), REU, tape interface (if you order it) etc.
If you are working with a ML program, there are several methods. If you aren't worried about ever returning to normal READY prompt without a RESET, you can have a small loader that loads into the stack ($0100-$01FF) The loader would just load the next section of code, then jump to it. It would start at $0102 and needs to be as small as possible. Many times, the next piece to load is only 2 characters, so the file name can be placed at $0100 & $0101. Then all you need to do is set LFS, SETNAM, LOAD, then JMP to it. Fill the rest of the stack area with $01. It is also rather safe to only save $0100-$010d so that the entire program will fit on a single disk block.
One issue with this, is that it clears out past stack entries (so, your program will need to reset the stack pointer back to the top.) If your program tries to do a normal RTS out of itself, random things can occur. If you want to exit the program, you'll need to jmp to the reset vector ($FFFC by default,) to do so.
What error checking do you do? What error checking is actually necessary? Do we really need to check if a file has saved successfully? Shouldn't it always work if it's tested and works ok from day one?
I find myself error checking for every little thing, and most of the time if feels overkill. Things like checking to see if a file has been written to a file system successfully, checking to see if a database statement failed.......shouldn't these be things that either work or don't?
How much error checking do you do? Are there elements of error checking that you leave out because you trust that it'll just work?
I'm sure I remember reading somewhere something along the lines of "don't test for things that'll never really happen".....can't remember the source though.
So should everything that could possibly fail be checked for failure? Or should we just trust those simpler operations? For example, if we can open a file, should we check to see if reading each line failed or not? Perhaps it depends on the context within the application or the application itself.
It'd be interesting to hear what others do.
UPDATE: As a quick example. I save an object that represents an image in a gallery. I then save the image to disc. If the saving of the file fails I'll have to image to display even though the object thinks there is an image. I could check for failure of the the image saving to disc and then delete the object, or alternatively wrap the image save in a transaction (unit of work) - but that can get expensive when using a db engine that uses table locking.
Thanks,
James.
if you run out of free space and try to write file and don't check errors your appliation will fall silently or with stupid messages. i hate when i see this in other apps.
I'm not addressing the entire question, just this part:
So should everything that could
possibly fail be checked for failure?
Or should we just trust those simpler
operations?
It seems to me that error checking is most important when the NEXT step matters. If failure to open a file will allow error messages to get permanently lost, then that is a problem. If the application will simply die and give the user an error, then I would consider that a different kind of problem. But silently dying, or silently hanging, is a problem that you should really do your best to code against. So whether something is a "simple operation" or not is irrelevant to me; it depends on what happens next, or what would be the result if it failed.
I generally follow these rules.
Excessively validate user input.
Validate public APIs.
Use Asserts that get compiled out of production code for everything else.
Regarding your example...
I save an object that represents an image in a gallery. I then save the image to disc. If the saving of the file fails I'll have [no] image to display even though the object thinks there is an image. I could check for failure of the the image saving to disc and then delete the object, or alternatively wrap the image save in a transaction (unit of work) - but that can get expensive when using a db engine that uses table locking.
In this case, I would recommend saving the image to disk first before saving the object. That way, if the image can't be saved, you don't have to try to roll back the gallery. In general, dependencies should get written to disk (or put in a database) first.
As for error checking... check for errors that make sense. If fopen() gives you a file ID and you don't get an error, then you don't generally need to check for fclose() on that file ID returning "invalid file ID". If, however, file opening and closing are disjoint tasks, it might be a good idea to check for that error.
This may not be the answer you are looking for, but there is only ever a 'right' answer when looked at in the full context of what you're trying to do.
If you're writing a prototype for internal use and if you get the odd error, it doens't matter, then you're wasting time and company money by adding in the extra checking.
On the other hand, if you're writing production software for air traffic control, then the extra time to handle every conceivable error may be well spent.
I see it as a trade off - extra time spent writing the error code versus the benefits of having handled that error if and when it occurs. Religiously handling every error is not necessary optimal IMO.