ftp 9802 through cRIO 9074

[Jolt]

Hello All,

Using the LV example I can apparently mount and write to a SC card in a 9802 module without problem. An example file is written to location u:\Example.txt

Unfortunately I cannot seem to FTP to that drive using the address ftp://xxx.xxx.xxx.xxx/u:/ (I can ftp to the controller, a cRIO 9074, without problem). When trying to connect to the SD card, internet explorer simply states that the page cannot be displayed. 

Various previous discussions talk about adding a property node (where should this go exactly?) that solves a conflict. Supposedly this issue was resolved recent versions of RIO.

Another discussion suggests that RIO 3.0.0 worked while RIO 3.1.0 failed in a similar way to what I am seeing - there doesn't seem to have been a resolution.

I'm running RIO 3.1.0 with EtherCAT Scan Engine Support from October 2008.

Ideas?

Thanks! 

[Charlie_P]

Good Evening Jolt,

The behavior you described is interesting.  Are you able to connect to the drives under your controller in MAX? You can accomplish this by right-clicking the controller under Remote Systems in MAX and selecting File Transfer.  Which drives appear under Remote Directory?

I will look into this issue and post to this thread when I have some more information.

[Jolt]

Thanks Charlie,

I don't have any obvious "Remote Systems" folder/drive as view from File Transfer in MAX.

General Question: When should the card(s) in a 9802 be visible to the outside word? Does this happen as soon as you put them in the slots? Does a card have to successfully mounted pragmatically before it shows up? What if its is then unmounted as in the example? Clearly I don't have a very good understanding of how these systems are working at a low level.

FYI, I can view the example.txt file by removing the card and reading in windows from a card reader.

Thanks,

[Charlie_P]

Hi Jolt,

When you say outside world, I assume you mean computer world.  As soon as your card is installed, the green LED on the NI 9802 will light, indicating that there is an SD card in the associated slot.  As far as computers are concerned, you need to have the SD card mounted.  When the card is unmounted it will not be visible or accessible by computers.

Mounting is the computer equivalent of giving your drive a name tag that an operating system can read.  Without mounting, an operating system doesn't know to "whom" to give the data.  Once a drive is mounted, the computer has a logical location to place data.

Mounting can only be avoided by writing to the SD card directly from an FPGA VI.  In this case, there is no operating system to require a predetermined location; the hardware is able to directly address the card.  This direct addressing is the reason the sustained 2 MB/sec transfer speed is only obtainable when accessing the NI 9802 from an FPGA VI instead of Real Time.  ("NI 9802 Write.lvproj" in the NI Example Finder, shows how to write to an SD card in the NI 9802 from an FPGA VI.)

Data Transfer Rate of the NI-9802 SD Module

     http://digital.ni.com/public.nsf/allkb/28C47A871DEB67918625751D0077BB93?OpenDocument

It is good news that you can read the example.txt from the card in a separate reader.  This confirms that your cRIO project is writing properly.  Try putting some kind of wait (preferably one which requires a user input before moving on) in the program that leaves the card mounted while you try to access the SD card over the network (either FTP or through Transfer Files in MAX).

[Jolt]

Thank you Charlie,

I really appreciate gaining underlying knowledge - especially when things don't seem to behave correctly!

Unfortunately, I have already tried almost exactly the suggestion you provide - I have modified the example VI "NI 9802 RT Access (Host)" from the example project "NI 9802 RT Access" to just wait in a loop and provide some feedback from a C-Series AI module - this ensures communication and operation. This hold loop is inserted just before the method "Unmount SD Card" meaning this method will not execute until the loop is stopped. Furthermore, this loop is after the "feedback" section of the example meaning I can verify that a files was written and get the relative path to that file (e.g. u:\example.txt)

I still do not have success from IE on my development PC.

FYI: I have played around with some of the various "scan engine" settings both in "Chassis" and "Target" properties - these values may matter here - what should they be? In the end my application will be running the scan engine for most I/O but accessing some DIO through the FPGA (think of a watchdog). It is my understanding that this is OK but could it be a problem for this file access operation?

Thanks!

[Charlie_P]

Hello Jolt,

The issue of being unable to FTP to the mounted SD card has now been reported by several customers.  This issue has been escalated to R&D and is on track to be fixed in a future release.  Thank you for your patience while this behavior is corrected.

For now, there is no simple workaround to access the files via FTP.  Until this is fixed, please use an external card reader to retrieve your data.

[Jolt]

Thank you - Cheers,

[Charlie_P]

This issue was resolved in NI-RIO 3.1.1.

[quarterlbr]

hi-

just stumbled upon this thread - i hope someone is still monitoring...

i've got a similar problem, (9074 w/9802) in that i can't access the card via ftp.  i can mount it and write to it, but i cant see it in ftp.

i mount it and assign it a drive letter.

through normal rt file vis, i write to the card.

i leave the card mounted until the program is terminated, so it should retain the drive letter - correct?

when i ftp to the card (via console ftp), i "cd" to the drive letter "x:" and the crio ftp server responds "Directory changed to "/u:/".  looks suspicious to me, but anyway, i try to "dir" the contents and I get a "451 I/O Error".

i've verified the contents of the card are there by removing the card and reading the contents via a card reader.

any idea what i'm doing incorrectly?

i have rio 3.1.1 installed.

thanks.

[quarterlbr · Accepted solution]

slight correction... i "cd" to the drive letter "u:" and the crio ftp server responds "Directory changed to "/u:/".   sorry for the error.

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quarterlbr wrote:

hi-

just stumbled upon this thread - i hope someone is still monitoring...

i've got a similar problem, (9074 w/9802) in that i can't access the card via ftp.  i can mount it and write to it, but i cant see it in ftp.

i mount it and assign it a drive letter.

through normal rt file vis, i write to the card.

i leave the card mounted until the program is terminated, so it should retain the drive letter - correct?

when i ftp to the card (via console ftp), i "cd" to the drive letter "x:" and the crio ftp server responds "Directory changed to "/u:/".  looks suspicious to me, but anyway, i try to "dir" the contents and I get a "451 I/O Error".

i've verified the contents of the card are there by removing the card and reading the contents via a card reader.

any idea what i'm doing incorrectly?

i have rio 3.1.1 installed.

thanks.

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