I'm working on a project that generates a lot of data (needs logging every 1s), so I'm using a CF card with a CR1000. It seems to be very slow (much slower than from logger memory) to download a file from the CF card. Is that to be expected?
I read that the currently open file on the CRD mustn't be downloaded using LoggerNet or it can corrupt the data. There doesn't seem to be any way in Loggernet to set which one to download automatically by either timestamp or a dynamically generated filename to prevent automatic download of the most recent file. Am I missing something?
I've not been able to find a way of sending these large files very reliably, see my other recent posts where I've tried FTP and emailrelay, with issues with both approaches.
I don't understand if there are many files generated every second or a file with data per second.
A file with data per second.
If your program uses CardOut(), regular data collection will grab data from the card in addition to data in RAM. No special consideration in that case.
If the datalogger program uses TableFile(), Loggernet needs to grab files apart from scheduled data collection. There is a file retrieval tab in Setup that allows configuration. A binary file format, such as option 64, is recommended for fastest possible download.
Using Loggernet to collect data or retrieve files will use Pakbus data transfers. It is reliable, but has noticeable throughput limits mostly based on connection latency. FTP transfers are more efficient for large files.
General practice for the IRGASON stations is TableFile() with Option 64 to save binary data. Then, use FTP to transfer those files. Daily file sizes are commonly chosen.
Thank you for the reply. I've used FTP previously, but in this case the client didn't want to pay for an FTP site. I've also had some issues with sending data using FTPS (for security), as in my other post.
I am using TableFile and option 64 as that seemed most appropriate when reading the documentation. Is there any way for LoggerNet to automate downloading eg the penultimate file from the CRD, but not the current one?
Is there any way for LoggerNet to automate downloading eg the penultimate file from the CRD, but not the current one?
The logger code is capable of renaming files. The Loggernet File Retrieval Tab has got file pattern recognition. Between those two features you should be able to work something out that lets Loggernet download the penultimate file only?
Yeah, true, another cunning work around. Not as straightforward as a built-in function though! ;-)