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Unread 05-08-2010, 19:59
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AKA: Marshal Horn
FRC #3213 (Thunder Tech)
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Re: Is the crio powerful enough?

An FPGA is not a processor. It does not have to work with only four bytes at a time. It doesn't have to grab data from a register, manipulate it, and then put it somewhere else in memory; it can just process the data continuously. It runs in parallel, like analog hardware. Think of it as a million operational amplifiers you can connect in whatever pattern you like, but instead of having to remanufacture it each time, you can reconfigure it electronically. In truth, it actually loads its configuration from non-volatile memory each time it is turned on, as opposed to it being burned in like a CD.

On the cRIO, there is a processor and an FPGA. I'm not sure about the ethernet or RS232, but I know that every one of the eight modules goes through the FPGA to get to the processor. For example, a small part of our FPGA is programmed as an accumulator for the gyro, to integrate degrees/second into absolute degrees. The FPGA is also used to improve the performance of the processor by acquiring data so that interrupts are rarely necessary; when the processor requests an input, the data is right there.

Now, as to how to get access to the FPGA: We aren't given the LabVIEW FPGA module in FRC. That's because
  1. It's believed to be too difficult for highschoolers in 6 weeks.
  2. It contains the system watchdog, and FIRST would be worried about safety hazards if it is disabled.
  3. It is a very valuble product of National Instruments, and it's a lot of what prevents loss of profit through piracy of the software we get for free. If we were to buy this software and a cRIO, it would be around $8,000 (single license).
Now, with that said, if you download a trial of LabVIEW, you have 30 days to play with it. LabVIEW 2010 just came out yesterday. It is common to have multiple versions of LabVIEW on a single computer without conflict, but if you like, feel free to back it up. After the 30 days, you license will expire, but your code will still be functional if it is deployed. If you'd like to use your code in LabVIEW 8.6, make sure to back-save it so that you can open it with the earlier version of LabVIEW.
When you'd like to use the cRIO for FIRST again, you will have to re-image.
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Last edited by kamocat : 05-08-2010 at 20:02. Reason: spellcheck