nochoochoo Posted August 13, 2009 Report Share Posted August 13, 2009 My company ran into a small issue... Background: National Instruments’ SD card module (NI-9802) enabled us to use a slower (and cheaper) chassis (NI-9073) but still collect a lot of data from our prototype. Problem: The SD cards are not easily accessible to whoever is running the system. This means that someone would have to undo panels and be exposed to the complete electronics panel. In short, it created a nuisance and a condition potentially hazardous to both the system and operator. Solution: In essence, we wanted to liberate the module from the chassis. This is not possible with current hardware setup and peripherals that NI offers. As you may now, the connection on the module is 3 rows of 5 pins each. A standard VGA cable won’t work because wires cross and merge. I found a company that sells VGA connections and made a cable myself. Wires go straight through, and there is a shield wire that is attached to the casing. With the aid of someone more experienced than me at a 3D CAD program, we created a harness that bolts to the outside shell and holds the module securely in place, much like the chassis. In addition, we attached a standard GFCI outdoor cover, which can be found at a hardware store, to protect it from the elements. There is also a place for a padlock to secure the cards against unwanted removal. Pros: Successfully separates module from chassis. Current setup also protects against the elements. Can separate modules and/or reorient them from the chassis. On the sb-RIO, all three slots can house a blue cased module and be secured. Cons: The plugs are held in place by friction alone. Both in the chassis and on the module. Harness must be unbolted in order to remove the module. Most likely cannot put a great distance between module and chassis. Has anybody else run into this problem? Have you tried anything else? Would you be interested in using this idea? Quote Link to comment
Chris Davis Posted August 14, 2009 Report Share Posted August 14, 2009 I'm not familiar with this cRIO module, but is it accessible to the RT system? If so, I believe you could FTP into the file system to see it. If not, you would probably have to build a custom server / client application to download the data through the 10/100 port. If none of these options appeal to you, perhaps an SD card that has the ability to upload the data on its own? I've seen such cards that work with digital cameras, uploading jpgs as you take them to your home computer... Just some random thoughts. Quote Link to comment
Anders Björk Posted August 14, 2009 Report Share Posted August 14, 2009 If you need the mechnical support why not buy a NI USB-9162 it would cost about 200-300$ http://sine.ni.com/nips/cds/view/p/lang/en/nid/204178 Quote Link to comment
nochoochoo Posted August 14, 2009 Author Report Share Posted August 14, 2009 I'm not familiar with this cRIO module, but is it accessible to the RT system? If so, I believe you could FTP into the file system to see it. If not, you would probably have to build a custom server / client application to download the data through the 10/100 port. If none of these options appeal to you, perhaps an SD card that has the ability to upload the data on its own? I've seen such cards that work with digital cameras, uploading jpgs as you take them to your home computer... Module itself is fairly new and I think has only been around since NIweek 2008... It is accesible to both the FPGA and the RT system. As of yet, I do not believe you can FTP files to and from the module. It would be possible to write a separate program that would go get the files and save them to the attached computer through the ethernet. In our situation, the system runs autonomously and a computer may not always be available to get the data. This way some one could get data by easily swapping out SD cards. I have not heard of this type of SD card. Thank you for the suggestion. If you need the mechnical support why not buy a NI USB-9162 it would cost about 200-300$ http://sine.ni.com/n...g/en/nid/204178 I'm not sure how the 9162 would help. Isn't it for hooking up directly to a computer? Or... Are you suggesting that we use the case for holding the module in place? If the latter, then we didn't use that because of a matter of cost and time. I had thought about using a dummy case in the chassis to secure that end of the cable... Quote Link to comment
Tom Limerkens Posted August 14, 2009 Report Share Posted August 14, 2009 Just my 2 cents, if it needs to be affordable... On the cRIO Backplane side, you could go for a NI 9977 module (about 30 USD/piece), and alter it, so you can use it as a 'backplane connector'. on the module side, couldn't you replace the fixing screws there with some type of standard 'screw-nuts' like used in DB9 extension cables ? Protocol over the DB15HD connector lines is SPI, but I have no idea about the speed, if you don't extend it for too long, I wouldn't expect a real problem... Tom Quote Link to comment
nochoochoo Posted August 14, 2009 Author Report Share Posted August 14, 2009 Just my 2 cents, if it needs to be affordable... On the cRIO Backplane side, you could go for a NI 9977 module (about 30 USD/piece), and alter it, so you can use it as a 'backplane connector'. on the module side, couldn't you replace the fixing screws there with some type of standard 'screw-nuts' like used in DB9 extension cables ? Protocol over the DB15HD connector lines is SPI, but I have no idea about the speed, if you don't extend it for too long, I wouldn't expect a real problem... Tom Yeah, great idea with the 9977! I don't know what the inside of one these looks like as far as hooking it up goes... About the screw nuts, I saw that they were "loctite"-ed and wasn't sure if removing them voided the warranty or something. Do you happen to know if the DB15HD cables are straight-through wires? (i.e. pins 4 and 8 aren't connected) Do you think that would just depend on the brand? I ended up making this cable... Speed doesn't seem to be affected. I only made our cable about 18 inches or so. Quote Link to comment
jgcode Posted August 15, 2009 Report Share Posted August 15, 2009 (edited) I do not believe you can FTP files to and from the module. (Haven't used it for a while) but I believe this is correct too Edited August 15, 2009 by jgcode Quote Link to comment
Tom Limerkens Posted August 16, 2009 Report Share Posted August 16, 2009 Do you happen to know if the DB15HD cables are straight-through wires? (i.e. pins 4 and 8 aren't connected) Do you think that would just depend on the brand? I ended up making this cable... Speed doesn't seem to be affected. I only made our cable about 18 inches or so. I would be very carefull by using a VGA extension cable, like you mention, not all pins are connected, and we have had some issues by using VGA cables with non-VGA devices (SICK Barcode scanners). There are companies that offer straight through DB15HD cables, I would go for such an option, or make them myself. Success, Tom Edit: Typo Quote Link to comment
nochoochoo Posted August 17, 2009 Author Report Share Posted August 17, 2009 Thanks Tom! After your last post, I found the same website but all I could find was VGA cables. Quote Link to comment
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