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rex1030

Hard Drive cRIO Modules

Status: New

We really need a hard drive crio module for long term monitoring and reliably storing large amounts of data remotely.

 

Hard-Drive-Module-Concept.png

 

Options:

 

1. Solid State Drive: Fast, reliable, and durable. Extremely high data rates. It would be a very high price module but it could be made to handle extreme temperatures and harsh conditions. It should be available in different capacities, varying in price.

 

2. Conventional Hard Drive: This would give any user the ability to store large amounts of storage, in the order of hundreds of Gigabytes. This type should also come in varying storage capacities.

 

For this to be useable:

 

1. It would need to support a file system other than FATxx. The risk of data corruption due to power loss/cycling during recording makes anything that uses this file system completely unreliable and utterly useless for long term monitoring. You can record for two months straight and then something goes wrong and you have nothing but a dead usb drive. So any other file system that is not so susceptible to corruption/damage due to power loss would be fine, reliance, NTFS, etc.

 

2. You should be able to plug in multiple modules and RAID them together for redundancy. This would insure data security and increase the usability of the cRIO for long term remote monitoring in almost any situation. 

 

 

Current cRIO storage issues:

We use NI products primarily in our lab and LabVIEW is awesome. I hope that while being very forward about our issues, we will not upset anyone or turn anyone away from any NI products.  However, attempting to use a cRIO device for long term remote monitoring has brought current storage shortfalls to the forefront and data loss has cost us dearly. These new hard drive modules would solve all the shortfalls of the current storage solutions for the crio. The biggest limitation of the cRIO for long term monitoring at the moment is the fact that it does not support a reliable file system on any external storage. The SD Card module has extremely fast data transfer rates but if power is lost while the SD card is mounted, not only is all the data lost, but the card needs to be physically removed from the device and reformatted with a PC. Even with the best UPS, this module is not suitable for long term monitoring. USB drives have a much slower data transfer rate and are susceptible to the same corruption due to power loss.

 

When we have brought up these issues in the past, the solution offered is to set up a reliable power backup system. It seems that those suggesting this have never tried to use the device with a large application in a situation where they have no physical access to the device, like 500 miles away. Unfortunately, the crio is susceptible to freezing or hanging up and becoming completely unresponsive over the network to a point that it can not be rebooted over the network at all. (Yes even with the setting about halting all processes if TCP becomes unresponsive). We would have to send someone all the way out to the device to hit the reset button or cycle power. Programs freeze, OS' freeze or crash, drivers crash, stuff happens. This should not put the data being stored at risk.

 

I would put money on something like this being already developed by NI. I hope you guys think the module is a good idea, even if you don't agree with all the problems I brought up. I searched around for an idea like this and my apologies if this is a re-post.

 

 

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[will work for kudos]
17 Comments
GoPSU
Member

I need this too. I was very surprised to find out there was a 4G limit, I may not be able to use cRIO and PXI is slightly too large for my embedded app.

 

Another solution is for them (someone) to develop a PATA direct access module. You then write to sector locations in raw mode on any PATA hard drive and mount it on your PC as a file (direct access mode, no file system). You would just have to come up with a format for streaming where the controller wouldn't allow overwrites due to some standard header being there. CF cards could be used too, they have an "IDE" mode 

Cale Brownstead
Ken3006
Member

I too support this idea.

 

There are a number of physical limitations in implementing the PXI platform in numerous headless monitoring application where the cRIO fits in perfectly.  Without extensive storage capabilities, we are limited in the development flexibility.

 

Alternative suggestions:

1. NTFS support for USB Drives on cRIO RT OS:

There are a number of companies out there doing embedded software development that are doing compatibility protocols for storage on real-time OS.  One such company is Tuxera (Product: Tuxera NTFS).  I am certain there are a number of issues to be tackled but perhaps you may look into this option?

 

2. Changes to the Removable Storage to allow modern high-density SD card.

 

Hope this could spark more interest. 🙂

 

Cheers,

Ken

 

QFang
Active Participant

We are in need of this as well.  It is very frustrating to not have support for Reliance/nitro/<insert robust file system here> on usb/external drives.

 

One option that I have not seen mentioned that could help "right now" (depending on your process) is this:  cRIO's have V1 and V2. NI support has told me it is possible to poll in software whether the cRIO is operating from V1 or V2.  By using any UPS or super-capacitor with enough oomph to run the cRIO for at least a few seconds, you could potentially close out files and put your cRIO software in a "safe state" so that when the power does go out, no file IO is ongoing. (I don't know where this/these VI's are.  I also don't know if there is an "unmount" command for usb/drives attached, but if no writes are in-process it should be fine to power cycle).

 

The only requirement (that I can think of) is that V2 is < V1 by at least 1 volt or so (so it always draws from V1 during normal operation). If you go the route of a super-capacitor, you could charge it trough a current limiter R from V1 source and just plop a diode or two in series to drop the max charge voltage.. you may not find a cap big enough though, depending on how fast you can stop file-access and how fast you can poll the "power source" bit in the cRIO.

 

We use the cRIO's without a backplane(!) and even though the spec for ours say max 6W, even while pegging CPU to 99-100%, continually broadcasting over (active) Ethernet (UDP) connection, and doing disk read and writes continually, we observed these power characteristics: Max 2.6W Min 2.1W Avg. 2.4 std.dev 0.09 (all stat's from period after 5000ms sleep seen below).

 

cRIO Power Draw.png

 

The new Linux cRIO's should make it possible to mount drivers to allow "any" file system to be accessed say over USB port.. so those you lucky to have that platform in your budget could go crazy with that!

QFang
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CLD LabVIEW 7.1 to 2016
CyGa
Active Participant

Hi everybody,

 

We've faced some many the memory capicty problem when working with cRIOs. And after reading this thread, we've decided to build our own cRIO SSD module.

And it works well ! We're thinking about selingl the module with the following capacities :

  • 128GB
  • 256GB
  • 512GB
  • 1TB

Attached to this thread is the maketing document for this module. You can find capacities available and technical details.

Do not hesitate to contact me directly (PM) if you think it would be a great product, and if you are interested in the module and prices !

 

 cRIO_SSD_Eng.png

CLA, CTA, LV Champion
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Jed_Davidow
Active Participant

Just checking, but this is a cRIO mountable USB drive? Is there any electrical connection on the cRIO bus? 

CyGa
Active Participant

Yes, it's a cRIO mountable USB drive. This is why no specific driver is needed. Moreover, using the USB port doesn't consume any FPGA space...

There is no connection to the cRIO backplane, but the subD-9 is still in place just to ensure a good mechanical integration in the chassis.

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NickNZ
Member

I see NI now has this product cRIO-9803

http://www.ni.com/en-nz/shop/select/expansion-module-for-compactrio

 

Manual is here.

http://www.ni.com/pdf/manuals/377727a.pdf

 

So think this should be marked implemented?

I was interested for storing large amounts of data. Table 2 is interesting as part of the FAT32 vs Ext3 storage.

It feels to me that Ext3 is the way to go - but then looks like a PITA to transfer data to windows.