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smithd

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smithd last won the day on December 3

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About smithd

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    LabVIEW 2013
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    2011

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  1. smithd

    [CR] SQLite Library

    I've used that in the past too, but i was creeped out today when I looked at it and saw that the downloads were http instead of https. The reason I noticed was that windows claimed the 32-bit version had a trojan. I'm assuming it was a false detection, but even if thats the case you shouldn't be serving up installers over an unsecure connection.
  2. smithd

    [CR] SQLite Library

    DB browser seems to only support png/bmp. I found a video suggesting jpeg support too, but the link said only via nightly builds
  3. smithd

    [CR] SQLite Library

    This is a pretty important piece of information. I took a quick look at their page (unfortunately their support forums are down, and there is no way I'm installing that software on my computer, so this is all I can go on) and it seems to say it supports bmp and jpg images. from your posts, you have so far provided it with: The pixel values of an image, type cast directly into a string with no metadata The NI vision software flattened representation of an image. I'd suggest the following: If you have a bmp or jpg image, use the read from binary file function with a elements to read set to -1 (to read the whole file as one big string) and pass that directly to sqlite. You may need to make sure that sqlite administrator knows the type, but i think bmp and jpg both use linux-style 'lets hide the extension inside the file' encoding, so its probably not necessary. If you have an imaqdx image in memory, use writestring (https://zone.ni.com/reference/en-XX/help/370281AD-01/imaqvision/imaq_write_string/) to generate a bmp or jpg string, and pass that directly to sqlite. To give a slightly more complete explanation, if you read the first few posts on this page we discuss the sqlite type system, which is very flexible -- in this case, everything is a string. You told everyone you wanted to store images in the database, which you were successfully doing in the formats described above. You did not explain that you had a very specific tool in mind for reading those images back out, and that is where the problem lies. It was expecting the string to be a specific format, and you were storing it not as that format.
  4. Shouldn't such absurd rules come with a budget? Like, no you can't take the machine out of the secure area but here why don't you just buy another instead?
  5. Lol sounds like intended behavior to punish those who ignore errors I think the missing part is that Tanner also added an incrementing counter on the send side, so you should see errors on every subsequent read because the counter will never catch up.
  6. Ah yes thats much nicer. I didn't know it could be broken up like that
  7. I dont think so, I forgot it was in there. Seems like a good idea though. Just needs to be added to TCP Master::Initialize Master and TCP Slave::wait on listener. This is illegal per the spec. Its obviously not difficult to change this, but...its also not hard just to set the value after initializing the modbus library. I think I see what you mean and attached an implementation. Looks to be about 3x faster (edit: 2x with debug off) to read from the lookup vs calculating it out. Just a thought tho, it probably makes other code around it slower by completely trashing your CPU cache (its about 1/4 of the L2 cache on a zynq-based cRIO). If visa times out it returns whatever is in the buffer. If it happens to time out mid-packet (as may be the case on linux rt or with usb-serial adapters) then you have half the packet in your read loop and half out on the bus. This isn't important for the master, since if you time out you pretty much have to flush the buffer, but for the slave its sitting there waiting for data forever, so dealing with partial packets is annoying. Also, this was like 6 years ago so I may be wrong, but at the time I think one of my goals was to make the serial and tcp functions act the same. Thats why TCP also uses the 'buffered' feature. I do, thats why I make sure to enable the term char. However it has to be CRLF, LF by itself is not acceptable. You may very well ask in which situation you would get a LF by itself -- I don't know, but I do know that its a 5c chip wiggling the voltage on some wires back and forth at an absurd speed, so I figure it can't hurt to check Woops. That method really only exists to make sure its not broadcast, so in the 99% use case it happens to work. Otherwise ascii doesn't care. Fixed, though. I don't actually understand what the problem was with this. As you said in your comment on that issue, each access should be synchronous for a given master or slave, so there is no such thing as multiple transactions outstanding on the connection. The transaction ID check just sort of verifies that. If an error occurs, you must close the connection and reset. I can't think of any reason that would not be the right response, can you? I'm also confused by this because that part of the code was implemented by Tanner, who is the person who posted that issue to yours, so presumably he thought that code fixed the issue? Note that this behavior (close and reopen) is different from serial (wait, flush the buffers, and hope things start to work again), not because the serial way is better but because serial is a 5c chip twiddling the voltage on some wires. The serial version has no connection to close. The idea of the pluggable transport was to support any modbus adu over any network type. I've definitely heard of RTU over TCP, this would be to support ascii over tcp the real answer is that it was easy and it kept the implementations mirrored. crc bench.vi crc.vi
  8. smithd

    [CR] SQLite Library

    I can't see what you're actually doing but I'd say this seems expected...sqlite has somewhat squishy types. https://www.sqlite.org/datatype3.html "Any column in an SQLite version 3 database, except an INTEGER PRIMARY KEY column, may be used to store a value of any storage class." "Any column can still store any type of data. It is just that some columns, given the choice, will prefer to use one storage class over another. The preferred storage class for a column is called its "affinity"." If that makes you feel bad, just remember that almost every interaction you have with your bank relies on a technology whose type system is pure madness.
  9. You might just ask your field sales. They can, on occasion, do nice things.
  10. However this will increase latency. That is the tradeoff. To be reasonably efficient with the network you'd need to transfer bursts of ~20 samples over wired ethernet. How real-time is real time? What does the labview code do with the information? Then my answer would be that you should write to a file, but as above it depends on exactly how important it is. What happens if you lose a sample? What happens if the network disconnects for 30 seconds? Yes, you would have to split the file up yourself. The strategy I follow is to have a directory /data with a file /data/temp.ext and a subdirectory /data/done which contains data1.ext, data2.ext, etc. I then use the built-in labview FTP (I believe the connectivity palette but I'm not sure) functions to fetch files out of the /data/done folder. That way I don't accidentally pull off a half-finished file. This appears to be automated in python: https://docs.python.org/3/library/logging.handlers.html#rotatingfilehandler and https://www.blog.pythonlibrary.org/2014/02/11/python-how-to-create-rotating-logs/ If you don't like FTP for some reason, someone put together a winscp wrapper library: https://lavag.org/topic/20474-free-labview-winscp-library/?tab=comments#comment-124582
  11. smithd

    creating .json file

    There does not appear to be anything standard about that 'normal' file. I don't think I've ever seen such a file before. To give you a clear picture of the complexity of what you are asking, and why drjd is quite right....just looking at that example I would assume the following about your file: The entire file is a single json object The first line is the 1 and only key within that object there is a CRLF between the key and its value The rest of the file is the value of the single key The single element is itself an object This object consists of key-value pairs separated by "-" and delimited by CRLF Every value is a string Your file cannot contain strings which contain CRLF Following these rules, your json output would be: {"Details": {"Name":"abc", "Organization": "anonymous", "Location": "xyz"}} If that is what you want, then my only answer is that you will have to procedurally parse the entire file from a string and construct the json object manually. If that is not what you want, then you should figure out the rules for your "normal simple" file. Once you figure out the rules, you will still have to manually write the code because that isn't a standard computer-parse-able format that I am aware of. If there are no rules, then you may need to consider a different strategy for whatever it is you are actually trying to accomplish. For example if you are making your files into json to make them easier for a computer to parse, then you'd be better of just shoving all these "normal simple" text files into elastic search or splunk and never look at them again.
  12. smithd

    LabVIEW 2018 SP1 Released

    the dev suite version worked for me without issue: http://www.ni.com/en-us/support/downloads/software-products/download.developer-suite-all-inclusive.html Downloaded about 5x faster than the web installer if you're also having trouble
  13. smithd

    LabVIEW 2018 SP1 Released

    Still broken, don't install To be clear I used the standalone installer for 32 bit since that took 3 minutes to download and the web installer would have taken 28 hours.
  14. I'm super confused...it sounds like you just want to stream data, right? So latency isn't important -- just throughput. So turning off nagle won't help. However you're introducing a latency issue by having LabVIEW request data by sending a string with "?" in it? The stated goal is 7 kHz * 50 bytes, which is 2.8 Mbit/s -- hardly anything. But when you introduce round trip communication into the streaming pathway, you're introducing slow performance. Can you clarify if there is an actual need for this back and forth? How important is reliability? If latency is unimportant and reliability is very important, I'd suggest writing your data to disk on the raspberry and then ftp/scp/webdav-ing it off. If reliability is not important, and this is on a local network, consider UDP.
  15. smithd

    LabVIEW 2018 SP1 Released

    This one also has the full suite web installer: http://www.ni.com/download/web-based-installer-labview-development-system-2018/7924/en/ and the full driver dvd http://www.ni.com/white-paper/55036/en/
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